ObjectOutputStream and ObjectInputStream can provide an application with - * persistent storage for graphs of objects when used with a FileOutputStream - * and FileInputStream respectively. ObjectInputStream is used to recover - * those objects previously serialized. Other uses include passing objects - * between hosts using a socket stream or for marshaling and unmarshaling - * arguments and parameters in a remote communication system. - * - *
ObjectInputStream ensures that the types of all objects in the graph - * created from the stream match the classes present in the Java Virtual - * Machine. Classes are loaded as required using the standard mechanisms. - * - *
Only objects that support the java.io.Serializable or - * java.io.Externalizable interface can be read from streams. - * - *
The method readObject is used to read an object from the
- * stream. Java's safe casting should be used to get the desired type. In
- * Java, strings and arrays are objects and are treated as objects during
- * serialization. When read they need to be cast to the expected type.
- *
- *
Primitive data types can be read from the stream using the appropriate - * method on DataInput. - * - *
The default deserialization mechanism for objects restores the contents - * of each field to the value and type it had when it was written. Fields - * declared as transient or static are ignored by the deserialization process. - * References to other objects cause those objects to be read from the stream - * as necessary. Graphs of objects are restored correctly using a reference - * sharing mechanism. New objects are always allocated when deserializing, - * which prevents existing objects from being overwritten. - * - *
Reading an object is analogous to running the constructors of a new - * object. Memory is allocated for the object and initialized to zero (NULL). - * No-arg constructors are invoked for the non-serializable classes and then - * the fields of the serializable classes are restored from the stream starting - * with the serializable class closest to java.lang.object and finishing with - * the object's most specific class. - * - *
For example to read from a stream as written by the example in
- * ObjectOutputStream:
- *
- *
- * FileInputStream fis = new FileInputStream("t.tmp");
- * ObjectInputStream ois = new ObjectInputStream(fis);
- *
- * int i = ois.readInt();
- * String today = (String) ois.readObject();
- * Date date = (Date) ois.readObject();
- *
- * ois.close();
- *
- *
- * Classes control how they are serialized by implementing either the - * java.io.Serializable or java.io.Externalizable interfaces. - * - *
Implementing the Serializable interface allows object serialization to - * save and restore the entire state of the object and it allows classes to - * evolve between the time the stream is written and the time it is read. It - * automatically traverses references between objects, saving and restoring - * entire graphs. - * - *
Serializable classes that require special handling during the - * serialization and deserialization process should implement the following - * methods:
- * - *
- * private void writeObject(java.io.ObjectOutputStream stream) - * throws IOException; - * private void readObject(java.io.ObjectInputStream stream) - * throws IOException, ClassNotFoundException; - * private void readObjectNoData() - * throws ObjectStreamException; - *- * - *
The readObject method is responsible for reading and restoring the state - * of the object for its particular class using data written to the stream by - * the corresponding writeObject method. The method does not need to concern - * itself with the state belonging to its superclasses or subclasses. State is - * restored by reading data from the ObjectInputStream for the individual - * fields and making assignments to the appropriate fields of the object. - * Reading primitive data types is supported by DataInput. - * - *
Any attempt to read object data which exceeds the boundaries of the - * custom data written by the corresponding writeObject method will cause an - * OptionalDataException to be thrown with an eof field value of true. - * Non-object reads which exceed the end of the allotted data will reflect the - * end of data in the same way that they would indicate the end of the stream: - * bytewise reads will return -1 as the byte read or number of bytes read, and - * primitive reads will throw EOFExceptions. If there is no corresponding - * writeObject method, then the end of default serialized data marks the end of - * the allotted data. - * - *
Primitive and object read calls issued from within a readExternal method
- * behave in the same manner--if the stream is already positioned at the end of
- * data written by the corresponding writeExternal method, object reads will
- * throw OptionalDataExceptions with eof set to true, bytewise reads will
- * return -1, and primitive reads will throw EOFExceptions. Note that this
- * behavior does not hold for streams written with the old
- * ObjectStreamConstants.PROTOCOL_VERSION_1 protocol, in which the
- * end of data written by writeExternal methods is not demarcated, and hence
- * cannot be detected.
- *
- *
The readObjectNoData method is responsible for initializing the state of - * the object for its particular class in the event that the serialization - * stream does not list the given class as a superclass of the object being - * deserialized. This may occur in cases where the receiving party uses a - * different version of the deserialized instance's class than the sending - * party, and the receiver's version extends classes that are not extended by - * the sender's version. This may also occur if the serialization stream has - * been tampered; hence, readObjectNoData is useful for initializing - * deserialized objects properly despite a "hostile" or incomplete source - * stream. - * - *
Serialization does not read or assign values to the fields of any object - * that does not implement the java.io.Serializable interface. Subclasses of - * Objects that are not serializable can be serializable. In this case the - * non-serializable class must have a no-arg constructor to allow its fields to - * be initialized. In this case it is the responsibility of the subclass to - * save and restore the state of the non-serializable class. It is frequently - * the case that the fields of that class are accessible (public, package, or - * protected) or that there are get and set methods that can be used to restore - * the state. - * - *
Any exception that occurs while deserializing an object will be caught by - * the ObjectInputStream and abort the reading process. - * - *
Implementing the Externalizable interface allows the object to assume - * complete control over the contents and format of the object's serialized - * form. The methods of the Externalizable interface, writeExternal and - * readExternal, are called to save and restore the objects state. When - * implemented by a class they can write and read their own state using all of - * the methods of ObjectOutput and ObjectInput. It is the responsibility of - * the objects to handle any versioning that occurs. - * - *
Enum constants are deserialized differently than ordinary serializable or
- * externalizable objects. The serialized form of an enum constant consists
- * solely of its name; field values of the constant are not transmitted. To
- * deserialize an enum constant, ObjectInputStream reads the constant name from
- * the stream; the deserialized constant is then obtained by calling the static
- * method If a security manager is installed, this constructor will check for
- * the "enableSubclassImplementation" SerializablePermission when invoked
- * directly or indirectly by the constructor of a subclass which overrides
- * the ObjectInputStream.readFields or ObjectInputStream.readUnshared
- * methods.
- *
- * @param in input stream to read from
- * @throws StreamCorruptedException if the stream header is incorrect
- * @throws IOException if an I/O error occurs while reading stream header
- * @throws SecurityException if untrusted subclass illegally overrides
- * security-sensitive methods
- * @throws NullPointerException if If there is a security manager installed, this method first calls the
- * security manager's The root object is completely restored when all of its fields and the
- * objects it references are completely restored. At this point the object
- * validation callbacks are executed in order based on their registered
- * priorities. The callbacks are registered by objects (in the readObject
- * special methods) as they are individually restored.
- *
- * Exceptions are thrown for problems with the InputStream and for
- * classes that should not be deserialized. All exceptions are fatal to
- * the InputStream and leave it in an indeterminate state; it is up to the
- * caller to ignore or recover the stream state.
- *
- * @throws ClassNotFoundException Class of a serialized object cannot be
- * found.
- * @throws InvalidClassException Something is wrong with a class used by
- * serialization.
- * @throws StreamCorruptedException Control information in the
- * stream is inconsistent.
- * @throws OptionalDataException Primitive data was found in the
- * stream instead of objects.
- * @throws IOException Any of the usual Input/Output related exceptions.
- */
- public final Object readObject()
- throws IOException, ClassNotFoundException
- {
- throw new IOException();
- }
-
- /**
- * This method is called by trusted subclasses of ObjectOutputStream that
- * constructed ObjectOutputStream using the protected no-arg constructor.
- * The subclass is expected to provide an override method with the modifier
- * "final".
- *
- * @return the Object read from the stream.
- * @throws ClassNotFoundException Class definition of a serialized object
- * cannot be found.
- * @throws OptionalDataException Primitive data was found in the stream
- * instead of objects.
- * @throws IOException if I/O errors occurred while reading from the
- * underlying stream
- * @see #ObjectInputStream()
- * @see #readObject()
- * @since 1.2
- */
- protected Object readObjectOverride()
- throws IOException, ClassNotFoundException
- {
- return null;
- }
-
- /**
- * Reads an "unshared" object from the ObjectInputStream. This method is
- * identical to readObject, except that it prevents subsequent calls to
- * readObject and readUnshared from returning additional references to the
- * deserialized instance obtained via this call. Specifically:
- * ObjectInputStream subclasses which override this method can only be
- * constructed in security contexts possessing the
- * "enableSubclassImplementation" SerializablePermission; any attempt to
- * instantiate such a subclass without this permission will cause a
- * SecurityException to be thrown.
- *
- * @return reference to deserialized object
- * @throws ClassNotFoundException if class of an object to deserialize
- * cannot be found
- * @throws StreamCorruptedException if control information in the stream
- * is inconsistent
- * @throws ObjectStreamException if object to deserialize has already
- * appeared in stream
- * @throws OptionalDataException if primitive data is next in stream
- * @throws IOException if an I/O error occurs during deserialization
- * @since 1.4
- */
- public Object readUnshared() throws IOException, ClassNotFoundException {
- // if nested read, passHandle contains handle of enclosing object
- int outerHandle = passHandle;
- try {
- Object obj = readObject0(true);
- handles.markDependency(outerHandle, passHandle);
- ClassNotFoundException ex = handles.lookupException(passHandle);
- if (ex != null) {
- throw ex;
- }
- if (depth == 0) {
- vlist.doCallbacks();
- }
- return obj;
- } finally {
- passHandle = outerHandle;
- if (closed && depth == 0) {
- clear();
- }
- }
- }
-
- /**
- * Read the non-static and non-transient fields of the current class from
- * this stream. This may only be called from the readObject method of the
- * class being deserialized. It will throw the NotActiveException if it is
- * called otherwise.
- *
- * @throws ClassNotFoundException if the class of a serialized object
- * could not be found.
- * @throws IOException if an I/O error occurs.
- * @throws NotActiveException if the stream is not currently reading
- * objects.
- */
- public void defaultReadObject()
- throws IOException, ClassNotFoundException
- {
- if (curContext == null) {
- throw new NotActiveException("not in call to readObject");
- }
- Object curObj = null; // curContext.getObj();
- ObjectStreamClass curDesc = null; // curContext.getDesc();
- bin.setBlockDataMode(false);
- defaultReadFields(curObj, curDesc);
- bin.setBlockDataMode(true);
- if (!curDesc.hasWriteObjectData()) {
- /*
- * Fix for 4360508: since stream does not contain terminating
- * TC_ENDBLOCKDATA tag, set flag so that reading code elsewhere
- * knows to simulate end-of-custom-data behavior.
- */
- defaultDataEnd = true;
- }
- ClassNotFoundException ex = handles.lookupException(passHandle);
- if (ex != null) {
- throw ex;
- }
- }
-
- /**
- * Reads the persistent fields from the stream and makes them available by
- * name.
- *
- * @return the The corresponding method in The default implementation of this method in
- * This method is called exactly once for each unique proxy class
- * descriptor in the stream.
- *
- * The corresponding method in The default implementation of this method in
- * This method is called after an object has been read but before it is
- * returned from readObject. The default resolveObject method just returns
- * the same object.
- *
- * When a subclass is replacing objects it must insure that the
- * substituted object is compatible with every field where the reference
- * will be stored. Objects whose type is not a subclass of the type of the
- * field or array element abort the serialization by raising an exception
- * and the object is not be stored.
- *
- * This method is called only once when each object is first
- * encountered. All subsequent references to the object will be redirected
- * to the new object.
- *
- * @param obj object to be substituted
- * @return the substituted object
- * @throws IOException Any of the usual Input/Output exceptions.
- */
- protected Object resolveObject(Object obj) throws IOException {
- return obj;
- }
-
- /**
- * Enable the stream to allow objects read from the stream to be replaced.
- * When enabled, the resolveObject method is called for every object being
- * deserialized.
- *
- * If enable is true, and there is a security manager installed,
- * this method first calls the security manager's
- * General use of the table is as follows: during deserialization, a
- * given object is first assigned a handle by calling the assign method.
- * This method leaves the assigned handle in an "open" state, wherein
- * dependencies on the exception status of other handles can be registered
- * by calling the markDependency method, or an exception can be directly
- * associated with the handle by calling markException. When a handle is
- * tagged with an exception, the HandleTable assumes responsibility for
- * propagating the exception to any other objects which depend
- * (transitively) on the exception-tagged object.
- *
- * Once all exception information/dependencies for the handle have been
- * registered, the handle should be "closed" by calling the finish method
- * on it. The act of finishing a handle allows the exception propagation
- * algorithm to aggressively prune dependency links, lessening the
- * performance/memory impact of exception tracking.
- *
- * Note that the exception propagation algorithm used depends on handles
- * being assigned/finished in LIFO order; however, for simplicity as well
- * as memory conservation, it does not enforce this constraint.
- */
- // REMIND: add full description of exception propagation algorithm?
- private static class HandleTable {
-
- /* status codes indicating whether object has associated exception */
- private static final byte STATUS_OK = 1;
- private static final byte STATUS_UNKNOWN = 2;
- private static final byte STATUS_EXCEPTION = 3;
-
- /** array mapping handle -> object status */
- byte[] status;
- /** array mapping handle -> object/exception (depending on status) */
- Object[] entries;
- /** array mapping handle -> list of dependent handles (if any) */
- HandleList[] deps;
- /** lowest unresolved dependency */
- int lowDep = -1;
- /** number of handles in table */
- int size = 0;
-
- /**
- * Creates handle table with the given initial capacity.
- */
- HandleTable(int initialCapacity) {
- status = new byte[initialCapacity];
- entries = new Object[initialCapacity];
- deps = new HandleList[initialCapacity];
- }
-
- /**
- * Assigns next available handle to given object, and returns assigned
- * handle. Once object has been completely deserialized (and all
- * dependencies on other objects identified), the handle should be
- * "closed" by passing it to finish().
- */
- int assign(Object obj) {
- if (size >= entries.length) {
- grow();
- }
- status[size] = STATUS_UNKNOWN;
- entries[size] = obj;
- return size++;
- }
-
- /**
- * Registers a dependency (in exception status) of one handle on
- * another. The dependent handle must be "open" (i.e., assigned, but
- * not finished yet). No action is taken if either dependent or target
- * handle is NULL_HANDLE.
- */
- void markDependency(int dependent, int target) {
- if (dependent == NULL_HANDLE || target == NULL_HANDLE) {
- return;
- }
- switch (status[dependent]) {
-
- case STATUS_UNKNOWN:
- switch (status[target]) {
- case STATUS_OK:
- // ignore dependencies on objs with no exception
- break;
-
- case STATUS_EXCEPTION:
- // eagerly propagate exception
- markException(dependent,
- (ClassNotFoundException) entries[target]);
- break;
-
- case STATUS_UNKNOWN:
- // add to dependency list of target
- if (deps[target] == null) {
- deps[target] = new HandleList();
- }
- deps[target].add(dependent);
-
- // remember lowest unresolved target seen
- if (lowDep < 0 || lowDep > target) {
- lowDep = target;
- }
- break;
-
- default:
- throw new InternalError();
- }
- break;
-
- case STATUS_EXCEPTION:
- break;
-
- default:
- throw new InternalError();
- }
- }
-
- /**
- * Associates a ClassNotFoundException (if one not already associated)
- * with the currently active handle and propagates it to other
- * referencing objects as appropriate. The specified handle must be
- * "open" (i.e., assigned, but not finished yet).
- */
- void markException(int handle, ClassNotFoundException ex) {
- switch (status[handle]) {
- case STATUS_UNKNOWN:
- status[handle] = STATUS_EXCEPTION;
- entries[handle] = ex;
-
- // propagate exception to dependents
- HandleList dlist = deps[handle];
- if (dlist != null) {
- int ndeps = dlist.size();
- for (int i = 0; i < ndeps; i++) {
- markException(dlist.get(i), ex);
- }
- deps[handle] = null;
- }
- break;
-
- case STATUS_EXCEPTION:
- break;
-
- default:
- throw new InternalError();
- }
- }
-
- /**
- * Marks given handle as finished, meaning that no new dependencies
- * will be marked for handle. Calls to the assign and finish methods
- * must occur in LIFO order.
- */
- void finish(int handle) {
- int end;
- if (lowDep < 0) {
- // no pending unknowns, only resolve current handle
- end = handle + 1;
- } else if (lowDep >= handle) {
- // pending unknowns now clearable, resolve all upward handles
- end = size;
- lowDep = -1;
- } else {
- // unresolved backrefs present, can't resolve anything yet
- return;
- }
-
- // change STATUS_UNKNOWN -> STATUS_OK in selected span of handles
- for (int i = handle; i < end; i++) {
- switch (status[i]) {
- case STATUS_UNKNOWN:
- status[i] = STATUS_OK;
- deps[i] = null;
- break;
-
- case STATUS_OK:
- case STATUS_EXCEPTION:
- break;
-
- default:
- throw new InternalError();
- }
- }
- }
-
- /**
- * Assigns a new object to the given handle. The object previously
- * associated with the handle is forgotten. This method has no effect
- * if the given handle already has an exception associated with it.
- * This method may be called at any time after the handle is assigned.
- */
- void setObject(int handle, Object obj) {
- switch (status[handle]) {
- case STATUS_UNKNOWN:
- case STATUS_OK:
- entries[handle] = obj;
- break;
-
- case STATUS_EXCEPTION:
- break;
-
- default:
- throw new InternalError();
- }
- }
-
- /**
- * Looks up and returns object associated with the given handle.
- * Returns null if the given handle is NULL_HANDLE, or if it has an
- * associated ClassNotFoundException.
- */
- Object lookupObject(int handle) {
- return (handle != NULL_HANDLE &&
- status[handle] != STATUS_EXCEPTION) ?
- entries[handle] : null;
- }
-
- /**
- * Looks up and returns ClassNotFoundException associated with the
- * given handle. Returns null if the given handle is NULL_HANDLE, or
- * if there is no ClassNotFoundException associated with the handle.
- */
- ClassNotFoundException lookupException(int handle) {
- return (handle != NULL_HANDLE &&
- status[handle] == STATUS_EXCEPTION) ?
- (ClassNotFoundException) entries[handle] : null;
- }
-
- /**
- * Resets table to its initial state.
- */
- void clear() {
- Arrays.fill(status, 0, size, (byte) 0);
- Arrays.fill(entries, 0, size, null);
- Arrays.fill(deps, 0, size, null);
- lowDep = -1;
- size = 0;
- }
-
- /**
- * Returns number of handles registered in table.
- */
- int size() {
- return size;
- }
-
- /**
- * Expands capacity of internal arrays.
- */
- private void grow() {
- int newCapacity = (entries.length << 1) + 1;
-
- byte[] newStatus = new byte[newCapacity];
- Object[] newEntries = new Object[newCapacity];
- HandleList[] newDeps = new HandleList[newCapacity];
-
- System.arraycopy(status, 0, newStatus, 0, size);
- System.arraycopy(entries, 0, newEntries, 0, size);
- System.arraycopy(deps, 0, newDeps, 0, size);
-
- status = newStatus;
- entries = newEntries;
- deps = newDeps;
- }
-
- /**
- * Simple growable list of (integer) handles.
- */
- private static class HandleList {
- private int[] list = new int[4];
- private int size = 0;
-
- public HandleList() {
- }
-
- public void add(int handle) {
- if (size >= list.length) {
- int[] newList = new int[list.length << 1];
- System.arraycopy(list, 0, newList, 0, list.length);
- list = newList;
- }
- list[size++] = handle;
- }
-
- public int get(int index) {
- if (index >= size) {
- throw new ArrayIndexOutOfBoundsException();
- }
- return list[index];
- }
-
- public int size() {
- return size;
- }
- }
- }
-
- /**
- * Method for cloning arrays in case of using unsharing reading
- */
- private static Object cloneArray(Object array) {
- if (array instanceof Object[]) {
- return ((Object[]) array).clone();
- } else if (array instanceof boolean[]) {
- return ((boolean[]) array).clone();
- } else if (array instanceof byte[]) {
- return ((byte[]) array).clone();
- } else if (array instanceof char[]) {
- return ((char[]) array).clone();
- } else if (array instanceof double[]) {
- return ((double[]) array).clone();
- } else if (array instanceof float[]) {
- return ((float[]) array).clone();
- } else if (array instanceof int[]) {
- return ((int[]) array).clone();
- } else if (array instanceof long[]) {
- return ((long[]) array).clone();
- } else if (array instanceof short[]) {
- return ((short[]) array).clone();
- } else {
- throw new AssertionError();
- }
- }
-
-}
Enum.valueOf(Class, String) with the enum constant's
- * base type and the received constant name as arguments. Like other
- * serializable or externalizable objects, enum constants can function as the
- * targets of back references appearing subsequently in the serialization
- * stream. The process by which enum constants are deserialized cannot be
- * customized: any class-specific readObject, readObjectNoData, and readResolve
- * methods defined by enum types are ignored during deserialization.
- * Similarly, any serialPersistentFields or serialVersionUID field declarations
- * are also ignored--all enum types have a fixed serialVersionUID of 0L.
- *
- * @author Mike Warres
- * @author Roger Riggs
- * @see java.io.DataInput
- * @see java.io.ObjectOutputStream
- * @see java.io.Serializable
- * @see Object Serialization Specification, Section 3, Object Input Classes
- * @since JDK1.1
- */
-public class ObjectInputStream
- extends InputStream implements ObjectInput, ObjectStreamConstants
-{
- /** handle value representing null */
- private static final int NULL_HANDLE = -1;
-
- /** marker for unshared objects in internal handle table */
- private static final Object unsharedMarker = new Object();
-
- /** table mapping primitive type names to corresponding class objects */
- private static final HashMapin is null
- * @see ObjectInputStream#ObjectInputStream()
- * @see ObjectInputStream#readFields()
- * @see ObjectOutputStream#ObjectOutputStream(OutputStream)
- */
- public ObjectInputStream(InputStream in) throws IOException {
- verifySubclass();
- bin = new BlockDataInputStream(in);
- handles = new HandleTable(10);
- vlist = new ValidationList();
- enableOverride = false;
- readStreamHeader();
- bin.setBlockDataMode(true);
- }
-
- /**
- * Provide a way for subclasses that are completely reimplementing
- * ObjectInputStream to not have to allocate private data just used by this
- * implementation of ObjectInputStream.
- *
- * checkPermission method with the
- * SerializablePermission("enableSubclassImplementation")
- * permission to ensure it's ok to enable subclassing.
- *
- * @throws SecurityException if a security manager exists and its
- * checkPermission method denies enabling
- * subclassing.
- * @see SecurityManager#checkPermission
- * @see java.io.SerializablePermission
- */
- protected ObjectInputStream() throws IOException, SecurityException {
- throw new SecurityException();
- }
-
- /**
- * Read an object from the ObjectInputStream. The class of the object, the
- * signature of the class, and the values of the non-transient and
- * non-static fields of the class and all of its supertypes are read.
- * Default deserializing for a class can be overriden using the writeObject
- * and readObject methods. Objects referenced by this object are read
- * transitively so that a complete equivalent graph of objects is
- * reconstructed by readObject.
- *
- *
- *
- * Deserializing an object via readUnshared invalidates the stream handle
- * associated with the returned object. Note that this in itself does not
- * always guarantee that the reference returned by readUnshared is unique;
- * the deserialized object may define a readResolve method which returns an
- * object visible to other parties, or readUnshared may return a Class
- * object or enum constant obtainable elsewhere in the stream or through
- * external means. If the deserialized object defines a readResolve method
- * and the invocation of that method returns an array, then readUnshared
- * returns a shallow clone of that array; this guarantees that the returned
- * array object is unique and cannot be obtained a second time from an
- * invocation of readObject or readUnshared on the ObjectInputStream,
- * even if the underlying data stream has been manipulated.
- *
- * GetField object representing the persistent
- * fields of the object being deserialized
- * @throws ClassNotFoundException if the class of a serialized object
- * could not be found.
- * @throws IOException if an I/O error occurs.
- * @throws NotActiveException if the stream is not currently reading
- * objects.
- * @since 1.2
- */
- public ObjectInputStream.GetField readFields()
- throws IOException, ClassNotFoundException
- {
- if (curContext == null) {
- throw new NotActiveException("not in call to readObject");
- }
- Object curObj = null; // curContext.getObj();
- ObjectStreamClass curDesc = null; // curContext.getDesc();
- bin.setBlockDataMode(false);
- GetFieldImpl getField = new GetFieldImpl(curDesc);
- getField.readFields();
- bin.setBlockDataMode(true);
- if (!curDesc.hasWriteObjectData()) {
- /*
- * Fix for 4360508: since stream does not contain terminating
- * TC_ENDBLOCKDATA tag, set flag so that reading code elsewhere
- * knows to simulate end-of-custom-data behavior.
- */
- defaultDataEnd = true;
- }
-
- return getField;
- }
-
- /**
- * Register an object to be validated before the graph is returned. While
- * similar to resolveObject these validations are called after the entire
- * graph has been reconstituted. Typically, a readObject method will
- * register the object with the stream so that when all of the objects are
- * restored a final set of validations can be performed.
- *
- * @param obj the object to receive the validation callback.
- * @param prio controls the order of callbacks;zero is a good default.
- * Use higher numbers to be called back earlier, lower numbers for
- * later callbacks. Within a priority, callbacks are processed in
- * no particular order.
- * @throws NotActiveException The stream is not currently reading objects
- * so it is invalid to register a callback.
- * @throws InvalidObjectException The validation object is null.
- */
- public void registerValidation(ObjectInputValidation obj, int prio)
- throws NotActiveException, InvalidObjectException
- {
- if (depth == 0) {
- throw new NotActiveException("stream inactive");
- }
- vlist.register(obj, prio);
- }
-
- /**
- * Load the local class equivalent of the specified stream class
- * description. Subclasses may implement this method to allow classes to
- * be fetched from an alternate source.
- *
- * ObjectOutputStream is
- * annotateClass. This method will be invoked only once for
- * each unique class in the stream. This method can be implemented by
- * subclasses to use an alternate loading mechanism but must return a
- * Class object. Once returned, if the class is not an array
- * class, its serialVersionUID is compared to the serialVersionUID of the
- * serialized class, and if there is a mismatch, the deserialization fails
- * and an {@link InvalidClassException} is thrown.
- *
- * ObjectInputStream returns the result of calling
- *
- * Class.forName(desc.getName(), false, loader)
- *
- * where loader is determined as follows: if there is a
- * method on the current thread's stack whose declaring class was
- * defined by a user-defined class loader (and was not a generated to
- * implement reflective invocations), then loader is class
- * loader corresponding to the closest such method to the currently
- * executing frame; otherwise, loader is
- * null. If this call results in a
- * ClassNotFoundException and the name of the passed
- * ObjectStreamClass instance is the Java language keyword
- * for a primitive type or void, then the Class object
- * representing that primitive type or void will be returned
- * (e.g., an ObjectStreamClass with the name
- * "int" will be resolved to Integer.TYPE).
- * Otherwise, the ClassNotFoundException will be thrown to
- * the caller of this method.
- *
- * @param desc an instance of class ObjectStreamClass
- * @return a Class object corresponding to desc
- * @throws IOException any of the usual Input/Output exceptions.
- * @throws ClassNotFoundException if class of a serialized object cannot
- * be found.
- */
- protected Class resolveClass(ObjectStreamClass desc)
- throws IOException, ClassNotFoundException
- {
- String name = desc.getName();
- try {
- return Class.forName(name, false, latestUserDefinedLoader());
- } catch (ClassNotFoundException ex) {
- Class cl = primClasses.get(name);
- if (cl != null) {
- return cl;
- } else {
- throw ex;
- }
- }
- }
-
- /**
- * Returns a proxy class that implements the interfaces named in a proxy
- * class descriptor; subclasses may implement this method to read custom
- * data from the stream along with the descriptors for dynamic proxy
- * classes, allowing them to use an alternate loading mechanism for the
- * interfaces and the proxy class.
- *
- * ObjectOutputStream is
- * annotateProxyClass. For a given subclass of
- * ObjectInputStream that overrides this method, the
- * annotateProxyClass method in the corresponding subclass of
- * ObjectOutputStream must write any data or objects read by
- * this method.
- *
- * ObjectInputStream returns the result of calling
- * Proxy.getProxyClass with the list of Class
- * objects for the interfaces that are named in the interfaces
- * parameter. The Class object for each interface name
- * i is the value returned by calling
- *
- * Class.forName(i, false, loader)
- *
- * where loader is that of the first non-null
- * class loader up the execution stack, or null if no
- * non-null class loaders are on the stack (the same class
- * loader choice used by the resolveClass method). Unless any
- * of the resolved interfaces are non-public, this same value of
- * loader is also the class loader passed to
- * Proxy.getProxyClass; if non-public interfaces are present,
- * their class loader is passed instead (if more than one non-public
- * interface class loader is encountered, an
- * IllegalAccessError is thrown).
- * If Proxy.getProxyClass throws an
- * IllegalArgumentException, resolveProxyClass
- * will throw a ClassNotFoundException containing the
- * IllegalArgumentException.
- *
- * @param interfaces the list of interface names that were
- * deserialized in the proxy class descriptor
- * @return a proxy class for the specified interfaces
- * @throws IOException any exception thrown by the underlying
- * InputStream
- * @throws ClassNotFoundException if the proxy class or any of the
- * named interfaces could not be found
- * @see ObjectOutputStream#annotateProxyClass(Class)
- * @since 1.3
- */
- protected Class resolveProxyClass(String[] interfaces)
- throws IOException, ClassNotFoundException
- {
- ClassLoader latestLoader = latestUserDefinedLoader();
- ClassLoader nonPublicLoader = null;
- boolean hasNonPublicInterface = false;
-
- // define proxy in class loader of non-public interface(s), if any
- Class[] classObjs = new Class[interfaces.length];
- for (int i = 0; i < interfaces.length; i++) {
- Class cl = Class.forName(interfaces[i], false, latestLoader);
- if ((cl.getModifiers() & Modifier.PUBLIC) == 0) {
- if (hasNonPublicInterface) {
- if (nonPublicLoader != cl.getClassLoader()) {
- throw new IllegalAccessError(
- "conflicting non-public interface class loaders");
- }
- } else {
- nonPublicLoader = cl.getClassLoader();
- hasNonPublicInterface = true;
- }
- }
- classObjs[i] = cl;
- }
- try {
- return Proxy.getProxyClass(
- hasNonPublicInterface ? nonPublicLoader : latestLoader,
- classObjs);
- } catch (IllegalArgumentException e) {
- throw new ClassNotFoundException(null, e);
- }
- }
-
- /**
- * This method will allow trusted subclasses of ObjectInputStream to
- * substitute one object for another during deserialization. Replacing
- * objects is disabled until enableResolveObject is called. The
- * enableResolveObject method checks that the stream requesting to resolve
- * object can be trusted. Every reference to serializable objects is passed
- * to resolveObject. To insure that the private state of objects is not
- * unintentionally exposed only trusted streams may use resolveObject.
- *
- * checkPermission method with the
- * SerializablePermission("enableSubstitution") permission to
- * ensure it's ok to enable the stream to allow objects read from the
- * stream to be replaced.
- *
- * @param enable true for enabling use of resolveObject for
- * every object being deserialized
- * @return the previous setting before this method was invoked
- * @throws SecurityException if a security manager exists and its
- * checkPermission method denies enabling the stream
- * to allow objects read from the stream to be replaced.
- * @see SecurityManager#checkPermission
- * @see java.io.SerializablePermission
- */
- protected boolean enableResolveObject(boolean enable)
- throws SecurityException
- {
- throw new SecurityException();
- }
-
- /**
- * The readStreamHeader method is provided to allow subclasses to read and
- * verify their own stream headers. It reads and verifies the magic number
- * and version number.
- *
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws StreamCorruptedException if control information in the stream
- * is inconsistent
- */
- protected void readStreamHeader()
- throws IOException, StreamCorruptedException
- {
- short s0 = bin.readShort();
- short s1 = bin.readShort();
- if (s0 != STREAM_MAGIC || s1 != STREAM_VERSION) {
- throw new StreamCorruptedException(
- String.format("invalid stream header: %04X%04X", s0, s1));
- }
- }
-
- /**
- * Read a class descriptor from the serialization stream. This method is
- * called when the ObjectInputStream expects a class descriptor as the next
- * item in the serialization stream. Subclasses of ObjectInputStream may
- * override this method to read in class descriptors that have been written
- * in non-standard formats (by subclasses of ObjectOutputStream which have
- * overridden the writeClassDescriptor method). By default,
- * this method reads class descriptors according to the format defined in
- * the Object Serialization specification.
- *
- * @return the class descriptor read
- * @throws IOException If an I/O error has occurred.
- * @throws ClassNotFoundException If the Class of a serialized object used
- * in the class descriptor representation cannot be found
- * @see java.io.ObjectOutputStream#writeClassDescriptor(java.io.ObjectStreamClass)
- * @since 1.3
- */
- protected ObjectStreamClass readClassDescriptor()
- throws IOException, ClassNotFoundException
- {
- ObjectStreamClass desc = new ObjectStreamClass();
- desc.readNonProxy(this);
- return desc;
- }
-
- /**
- * Reads a byte of data. This method will block if no input is available.
- *
- * @return the byte read, or -1 if the end of the stream is reached.
- * @throws IOException If an I/O error has occurred.
- */
- public int read() throws IOException {
- return bin.read();
- }
-
- /**
- * Reads into an array of bytes. This method will block until some input
- * is available. Consider using java.io.DataInputStream.readFully to read
- * exactly 'length' bytes.
- *
- * @param buf the buffer into which the data is read
- * @param off the start offset of the data
- * @param len the maximum number of bytes read
- * @return the actual number of bytes read, -1 is returned when the end of
- * the stream is reached.
- * @throws IOException If an I/O error has occurred.
- * @see java.io.DataInputStream#readFully(byte[],int,int)
- */
- public int read(byte[] buf, int off, int len) throws IOException {
- if (buf == null) {
- throw new NullPointerException();
- }
- int endoff = off + len;
- if (off < 0 || len < 0 || endoff > buf.length || endoff < 0) {
- throw new IndexOutOfBoundsException();
- }
- return bin.read(buf, off, len, false);
- }
-
- /**
- * Returns the number of bytes that can be read without blocking.
- *
- * @return the number of available bytes.
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- */
- public int available() throws IOException {
- return bin.available();
- }
-
- /**
- * Closes the input stream. Must be called to release any resources
- * associated with the stream.
- *
- * @throws IOException If an I/O error has occurred.
- */
- public void close() throws IOException {
- /*
- * Even if stream already closed, propagate redundant close to
- * underlying stream to stay consistent with previous implementations.
- */
- closed = true;
- if (depth == 0) {
- clear();
- }
- bin.close();
- }
-
- /**
- * Reads in a boolean.
- *
- * @return the boolean read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public boolean readBoolean() throws IOException {
- return bin.readBoolean();
- }
-
- /**
- * Reads an 8 bit byte.
- *
- * @return the 8 bit byte read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public byte readByte() throws IOException {
- return bin.readByte();
- }
-
- /**
- * Reads an unsigned 8 bit byte.
- *
- * @return the 8 bit byte read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public int readUnsignedByte() throws IOException {
- return bin.readUnsignedByte();
- }
-
- /**
- * Reads a 16 bit char.
- *
- * @return the 16 bit char read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public char readChar() throws IOException {
- return bin.readChar();
- }
-
- /**
- * Reads a 16 bit short.
- *
- * @return the 16 bit short read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public short readShort() throws IOException {
- return bin.readShort();
- }
-
- /**
- * Reads an unsigned 16 bit short.
- *
- * @return the 16 bit short read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public int readUnsignedShort() throws IOException {
- return bin.readUnsignedShort();
- }
-
- /**
- * Reads a 32 bit int.
- *
- * @return the 32 bit integer read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public int readInt() throws IOException {
- return bin.readInt();
- }
-
- /**
- * Reads a 64 bit long.
- *
- * @return the read 64 bit long.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public long readLong() throws IOException {
- return bin.readLong();
- }
-
- /**
- * Reads a 32 bit float.
- *
- * @return the 32 bit float read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public float readFloat() throws IOException {
- return bin.readFloat();
- }
-
- /**
- * Reads a 64 bit double.
- *
- * @return the 64 bit double read.
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public double readDouble() throws IOException {
- return bin.readDouble();
- }
-
- /**
- * Reads bytes, blocking until all bytes are read.
- *
- * @param buf the buffer into which the data is read
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public void readFully(byte[] buf) throws IOException {
- bin.readFully(buf, 0, buf.length, false);
- }
-
- /**
- * Reads bytes, blocking until all bytes are read.
- *
- * @param buf the buffer into which the data is read
- * @param off the start offset of the data
- * @param len the maximum number of bytes to read
- * @throws EOFException If end of file is reached.
- * @throws IOException If other I/O error has occurred.
- */
- public void readFully(byte[] buf, int off, int len) throws IOException {
- int endoff = off + len;
- if (off < 0 || len < 0 || endoff > buf.length || endoff < 0) {
- throw new IndexOutOfBoundsException();
- }
- bin.readFully(buf, off, len, false);
- }
-
- /**
- * Skips bytes.
- *
- * @param len the number of bytes to be skipped
- * @return the actual number of bytes skipped.
- * @throws IOException If an I/O error has occurred.
- */
- public int skipBytes(int len) throws IOException {
- return bin.skipBytes(len);
- }
-
- /**
- * Reads in a line that has been terminated by a \n, \r, \r\n or EOF.
- *
- * @return a String copy of the line.
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @deprecated This method does not properly convert bytes to characters.
- * see DataInputStream for the details and alternatives.
- */
- @Deprecated
- public String readLine() throws IOException {
- return bin.readLine();
- }
-
- /**
- * Reads a String in
- * modified UTF-8
- * format.
- *
- * @return the String.
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws UTFDataFormatException if read bytes do not represent a valid
- * modified UTF-8 encoding of a string
- */
- public String readUTF() throws IOException {
- return bin.readUTF();
- }
-
- /**
- * Provide access to the persistent fields read from the input stream.
- */
- public static abstract class GetField {
-
- /**
- * Get the ObjectStreamClass that describes the fields in the stream.
- *
- * @return the descriptor class that describes the serializable fields
- */
- public abstract ObjectStreamClass getObjectStreamClass();
-
- /**
- * Return true if the named field is defaulted and has no value in this
- * stream.
- *
- * @param name the name of the field
- * @return true, if and only if the named field is defaulted
- * @throws IOException if there are I/O errors while reading from
- * the underlying InputStream
- * @throws IllegalArgumentException if name does not
- * correspond to a serializable field
- */
- public abstract boolean defaulted(String name) throws IOException;
-
- /**
- * Get the value of the named boolean field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named boolean field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract boolean get(String name, boolean val)
- throws IOException;
-
- /**
- * Get the value of the named byte field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named byte field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract byte get(String name, byte val) throws IOException;
-
- /**
- * Get the value of the named char field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named char field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract char get(String name, char val) throws IOException;
-
- /**
- * Get the value of the named short field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named short field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract short get(String name, short val) throws IOException;
-
- /**
- * Get the value of the named int field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named int field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract int get(String name, int val) throws IOException;
-
- /**
- * Get the value of the named long field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named long field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract long get(String name, long val) throws IOException;
-
- /**
- * Get the value of the named float field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named float field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract float get(String name, float val) throws IOException;
-
- /**
- * Get the value of the named double field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named double field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract double get(String name, double val) throws IOException;
-
- /**
- * Get the value of the named Object field from the persistent field.
- *
- * @param name the name of the field
- * @param val the default value to use if name does not
- * have a value
- * @return the value of the named Object field
- * @throws IOException if there are I/O errors while reading from the
- * underlying InputStream
- * @throws IllegalArgumentException if type of name is
- * not serializable or if the field type is incorrect
- */
- public abstract Object get(String name, Object val) throws IOException;
- }
-
- /**
- * Verifies that this (possibly subclass) instance can be constructed
- * without violating security constraints: the subclass must not override
- * security-sensitive non-final methods, or else the
- * "enableSubclassImplementation" SerializablePermission is checked.
- */
- private void verifySubclass() {
- Class cl = getClass();
- if (cl == ObjectInputStream.class) {
- return;
- }
- throw new SecurityException();
- }
-
- /**
- * Clears internal data structures.
- */
- private void clear() {
- handles.clear();
- vlist.clear();
- }
-
- /**
- * Underlying readObject implementation.
- */
- private Object readObject0(boolean unshared) throws IOException {
- boolean oldMode = bin.getBlockDataMode();
- if (oldMode) {
- int remain = bin.currentBlockRemaining();
- if (remain > 0) {
- throw new OptionalDataException(remain);
- } else if (defaultDataEnd) {
- /*
- * Fix for 4360508: stream is currently at the end of a field
- * value block written via default serialization; since there
- * is no terminating TC_ENDBLOCKDATA tag, simulate
- * end-of-custom-data behavior explicitly.
- */
- throw new OptionalDataException(true);
- }
- bin.setBlockDataMode(false);
- }
-
- byte tc;
- while ((tc = bin.peekByte()) == TC_RESET) {
- bin.readByte();
- handleReset();
- }
-
- depth++;
- try {
- switch (tc) {
- case TC_NULL:
- return readNull();
-
- case TC_REFERENCE:
- return readHandle(unshared);
-
- case TC_CLASS:
- return readClass(unshared);
-
- case TC_CLASSDESC:
- case TC_PROXYCLASSDESC:
- return readClassDesc(unshared);
-
- case TC_STRING:
- case TC_LONGSTRING:
- return checkResolve(readString(unshared));
-
- case TC_ARRAY:
- return checkResolve(readArray(unshared));
-
- case TC_ENUM:
- return checkResolve(readEnum(unshared));
-
- case TC_OBJECT:
- return checkResolve(readOrdinaryObject(unshared));
-
- case TC_EXCEPTION:
- IOException ex = readFatalException();
- throw new WriteAbortedException("writing aborted", ex);
-
- case TC_BLOCKDATA:
- case TC_BLOCKDATALONG:
- if (oldMode) {
- bin.setBlockDataMode(true);
- bin.peek(); // force header read
- throw new OptionalDataException(
- bin.currentBlockRemaining());
- } else {
- throw new StreamCorruptedException(
- "unexpected block data");
- }
-
- case TC_ENDBLOCKDATA:
- if (oldMode) {
- throw new OptionalDataException(true);
- } else {
- throw new StreamCorruptedException(
- "unexpected end of block data");
- }
-
- default:
- throw new StreamCorruptedException(
- String.format("invalid type code: %02X", tc));
- }
- } finally {
- depth--;
- bin.setBlockDataMode(oldMode);
- }
- }
-
- /**
- * If resolveObject has been enabled and given object does not have an
- * exception associated with it, calls resolveObject to determine
- * replacement for object, and updates handle table accordingly. Returns
- * replacement object, or echoes provided object if no replacement
- * occurred. Expects that passHandle is set to given object's handle prior
- * to calling this method.
- */
- private Object checkResolve(Object obj) throws IOException {
- if (!enableResolve || handles.lookupException(passHandle) != null) {
- return obj;
- }
- Object rep = resolveObject(obj);
- if (rep != obj) {
- handles.setObject(passHandle, rep);
- }
- return rep;
- }
-
- /**
- * Reads string without allowing it to be replaced in stream. Called from
- * within ObjectStreamClass.read().
- */
- String readTypeString() throws IOException {
- int oldHandle = passHandle;
- try {
- byte tc = bin.peekByte();
- switch (tc) {
- case TC_NULL:
- return (String) readNull();
-
- case TC_REFERENCE:
- return (String) readHandle(false);
-
- case TC_STRING:
- case TC_LONGSTRING:
- return readString(false);
-
- default:
- throw new StreamCorruptedException(
- String.format("invalid type code: %02X", tc));
- }
- } finally {
- passHandle = oldHandle;
- }
- }
-
- /**
- * Reads in null code, sets passHandle to NULL_HANDLE and returns null.
- */
- private Object readNull() throws IOException {
- if (bin.readByte() != TC_NULL) {
- throw new InternalError();
- }
- passHandle = NULL_HANDLE;
- return null;
- }
-
- /**
- * Reads in object handle, sets passHandle to the read handle, and returns
- * object associated with the handle.
- */
- private Object readHandle(boolean unshared) throws IOException {
- if (bin.readByte() != TC_REFERENCE) {
- throw new InternalError();
- }
- passHandle = bin.readInt() - baseWireHandle;
- if (passHandle < 0 || passHandle >= handles.size()) {
- throw new StreamCorruptedException(
- String.format("invalid handle value: %08X", passHandle +
- baseWireHandle));
- }
- if (unshared) {
- // REMIND: what type of exception to throw here?
- throw new InvalidObjectException(
- "cannot read back reference as unshared");
- }
-
- Object obj = handles.lookupObject(passHandle);
- if (obj == unsharedMarker) {
- // REMIND: what type of exception to throw here?
- throw new InvalidObjectException(
- "cannot read back reference to unshared object");
- }
- return obj;
- }
-
- /**
- * Reads in and returns class object. Sets passHandle to class object's
- * assigned handle. Returns null if class is unresolvable (in which case a
- * ClassNotFoundException will be associated with the class' handle in the
- * handle table).
- */
- private Class readClass(boolean unshared) throws IOException {
- if (bin.readByte() != TC_CLASS) {
- throw new InternalError();
- }
- ObjectStreamClass desc = readClassDesc(false);
- Class cl = desc.forClass();
- passHandle = handles.assign(unshared ? unsharedMarker : cl);
-
- ClassNotFoundException resolveEx = desc.getResolveException();
- if (resolveEx != null) {
- handles.markException(passHandle, resolveEx);
- }
-
- handles.finish(passHandle);
- return cl;
- }
-
- /**
- * Reads in and returns (possibly null) class descriptor. Sets passHandle
- * to class descriptor's assigned handle. If class descriptor cannot be
- * resolved to a class in the local VM, a ClassNotFoundException is
- * associated with the class descriptor's handle.
- */
- private ObjectStreamClass readClassDesc(boolean unshared)
- throws IOException
- {
- byte tc = bin.peekByte();
- switch (tc) {
- case TC_NULL:
- return (ObjectStreamClass) readNull();
-
- case TC_REFERENCE:
- return (ObjectStreamClass) readHandle(unshared);
-
- case TC_PROXYCLASSDESC:
- return readProxyDesc(unshared);
-
- case TC_CLASSDESC:
- return readNonProxyDesc(unshared);
-
- default:
- throw new StreamCorruptedException(
- String.format("invalid type code: %02X", tc));
- }
- }
-
- /**
- * Reads in and returns class descriptor for a dynamic proxy class. Sets
- * passHandle to proxy class descriptor's assigned handle. If proxy class
- * descriptor cannot be resolved to a class in the local VM, a
- * ClassNotFoundException is associated with the descriptor's handle.
- */
- private ObjectStreamClass readProxyDesc(boolean unshared)
- throws IOException
- {
- if (bin.readByte() != TC_PROXYCLASSDESC) {
- throw new InternalError();
- }
-
- ObjectStreamClass desc = new ObjectStreamClass();
- int descHandle = handles.assign(unshared ? unsharedMarker : desc);
- passHandle = NULL_HANDLE;
-
- int numIfaces = bin.readInt();
- String[] ifaces = new String[numIfaces];
- for (int i = 0; i < numIfaces; i++) {
- ifaces[i] = bin.readUTF();
- }
-
- Class cl = null;
- ClassNotFoundException resolveEx = null;
- bin.setBlockDataMode(true);
- try {
- if ((cl = resolveProxyClass(ifaces)) == null) {
- resolveEx = new ClassNotFoundException("null class");
- }
- } catch (ClassNotFoundException ex) {
- resolveEx = ex;
- }
- skipCustomData();
-
- desc.initProxy(cl, resolveEx, readClassDesc(false));
-
- handles.finish(descHandle);
- passHandle = descHandle;
- return desc;
- }
-
- /**
- * Reads in and returns class descriptor for a class that is not a dynamic
- * proxy class. Sets passHandle to class descriptor's assigned handle. If
- * class descriptor cannot be resolved to a class in the local VM, a
- * ClassNotFoundException is associated with the descriptor's handle.
- */
- private ObjectStreamClass readNonProxyDesc(boolean unshared)
- throws IOException
- {
- if (bin.readByte() != TC_CLASSDESC) {
- throw new InternalError();
- }
-
- ObjectStreamClass desc = new ObjectStreamClass();
- int descHandle = handles.assign(unshared ? unsharedMarker : desc);
- passHandle = NULL_HANDLE;
-
- ObjectStreamClass readDesc = null;
- try {
- readDesc = readClassDescriptor();
- } catch (ClassNotFoundException ex) {
- throw (IOException) new InvalidClassException(
- "failed to read class descriptor").initCause(ex);
- }
-
- Class cl = null;
- ClassNotFoundException resolveEx = null;
- bin.setBlockDataMode(true);
- try {
- if ((cl = resolveClass(readDesc)) == null) {
- resolveEx = new ClassNotFoundException("null class");
- }
- } catch (ClassNotFoundException ex) {
- resolveEx = ex;
- }
- skipCustomData();
-
- desc.initNonProxy(readDesc, cl, resolveEx, readClassDesc(false));
-
- handles.finish(descHandle);
- passHandle = descHandle;
- return desc;
- }
-
- /**
- * Reads in and returns new string. Sets passHandle to new string's
- * assigned handle.
- */
- private String readString(boolean unshared) throws IOException {
- String str;
- byte tc = bin.readByte();
- switch (tc) {
- case TC_STRING:
- str = bin.readUTF();
- break;
-
- case TC_LONGSTRING:
- str = bin.readLongUTF();
- break;
-
- default:
- throw new StreamCorruptedException(
- String.format("invalid type code: %02X", tc));
- }
- passHandle = handles.assign(unshared ? unsharedMarker : str);
- handles.finish(passHandle);
- return str;
- }
-
- /**
- * Reads in and returns array object, or null if array class is
- * unresolvable. Sets passHandle to array's assigned handle.
- */
- private Object readArray(boolean unshared) throws IOException {
- if (bin.readByte() != TC_ARRAY) {
- throw new InternalError();
- }
-
- ObjectStreamClass desc = readClassDesc(false);
- int len = bin.readInt();
-
- Object array = null;
- Class cl, ccl = null;
- if ((cl = desc.forClass()) != null) {
- ccl = cl.getComponentType();
- array = Array.newInstance(ccl, len);
- }
-
- int arrayHandle = handles.assign(unshared ? unsharedMarker : array);
- ClassNotFoundException resolveEx = desc.getResolveException();
- if (resolveEx != null) {
- handles.markException(arrayHandle, resolveEx);
- }
-
- if (ccl == null) {
- for (int i = 0; i < len; i++) {
- readObject0(false);
- }
- } else if (ccl.isPrimitive()) {
- if (ccl == Integer.TYPE) {
- bin.readInts((int[]) array, 0, len);
- } else if (ccl == Byte.TYPE) {
- bin.readFully((byte[]) array, 0, len, true);
- } else if (ccl == Long.TYPE) {
- bin.readLongs((long[]) array, 0, len);
- } else if (ccl == Float.TYPE) {
- bin.readFloats((float[]) array, 0, len);
- } else if (ccl == Double.TYPE) {
- bin.readDoubles((double[]) array, 0, len);
- } else if (ccl == Short.TYPE) {
- bin.readShorts((short[]) array, 0, len);
- } else if (ccl == Character.TYPE) {
- bin.readChars((char[]) array, 0, len);
- } else if (ccl == Boolean.TYPE) {
- bin.readBooleans((boolean[]) array, 0, len);
- } else {
- throw new InternalError();
- }
- } else {
- Object[] oa = (Object[]) array;
- for (int i = 0; i < len; i++) {
- oa[i] = readObject0(false);
- handles.markDependency(arrayHandle, passHandle);
- }
- }
-
- handles.finish(arrayHandle);
- passHandle = arrayHandle;
- return array;
- }
-
- /**
- * Reads in and returns enum constant, or null if enum type is
- * unresolvable. Sets passHandle to enum constant's assigned handle.
- */
- private Enum readEnum(boolean unshared) throws IOException {
- if (bin.readByte() != TC_ENUM) {
- throw new InternalError();
- }
-
- ObjectStreamClass desc = readClassDesc(false);
- if (!desc.isEnum()) {
- throw new InvalidClassException("non-enum class: " + desc);
- }
-
- int enumHandle = handles.assign(unshared ? unsharedMarker : null);
- ClassNotFoundException resolveEx = desc.getResolveException();
- if (resolveEx != null) {
- handles.markException(enumHandle, resolveEx);
- }
-
- String name = readString(false);
- Enum en = null;
- Class cl = desc.forClass();
- if (cl != null) {
- try {
- en = Enum.valueOf(cl, name);
- } catch (IllegalArgumentException ex) {
- throw (IOException) new InvalidObjectException(
- "enum constant " + name + " does not exist in " +
- cl).initCause(ex);
- }
- if (!unshared) {
- handles.setObject(enumHandle, en);
- }
- }
-
- handles.finish(enumHandle);
- passHandle = enumHandle;
- return en;
- }
-
- /**
- * Reads and returns "ordinary" (i.e., not a String, Class,
- * ObjectStreamClass, array, or enum constant) object, or null if object's
- * class is unresolvable (in which case a ClassNotFoundException will be
- * associated with object's handle). Sets passHandle to object's assigned
- * handle.
- */
- private Object readOrdinaryObject(boolean unshared)
- throws IOException
- {
- if (bin.readByte() != TC_OBJECT) {
- throw new InternalError();
- }
-
- ObjectStreamClass desc = readClassDesc(false);
- desc.checkDeserialize();
-
- Object obj;
- try {
- obj = desc.isInstantiable() ? desc.newInstance() : null;
- } catch (Exception ex) {
- throw (IOException) new InvalidClassException(
- desc.forClass().getName(),
- "unable to create instance").initCause(ex);
- }
-
- passHandle = handles.assign(unshared ? unsharedMarker : obj);
- ClassNotFoundException resolveEx = desc.getResolveException();
- if (resolveEx != null) {
- handles.markException(passHandle, resolveEx);
- }
-
- if (desc.isExternalizable()) {
- readExternalData((Externalizable) obj, desc);
- } else {
- readSerialData(obj, desc);
- }
-
- handles.finish(passHandle);
-
- if (obj != null &&
- handles.lookupException(passHandle) == null &&
- desc.hasReadResolveMethod())
- {
- Object rep = desc.invokeReadResolve(obj);
- if (unshared && rep.getClass().isArray()) {
- rep = cloneArray(rep);
- }
- if (rep != obj) {
- handles.setObject(passHandle, obj = rep);
- }
- }
-
- return obj;
- }
-
- /**
- * If obj is non-null, reads externalizable data by invoking readExternal()
- * method of obj; otherwise, attempts to skip over externalizable data.
- * Expects that passHandle is set to obj's handle before this method is
- * called.
- */
- private void readExternalData(Externalizable obj, ObjectStreamClass desc)
- throws IOException
- {
- Object oldContext = curContext;
- curContext = null;
- try {
- boolean blocked = desc.hasBlockExternalData();
- if (blocked) {
- bin.setBlockDataMode(true);
- }
- if (obj != null) {
- try {
- obj.readExternal(this);
- } catch (ClassNotFoundException ex) {
- /*
- * In most cases, the handle table has already propagated
- * a CNFException to passHandle at this point; this mark
- * call is included to address cases where the readExternal
- * method has cons'ed and thrown a new CNFException of its
- * own.
- */
- handles.markException(passHandle, ex);
- }
- }
- if (blocked) {
- skipCustomData();
- }
- } finally {
- curContext = oldContext;
- }
- /*
- * At this point, if the externalizable data was not written in
- * block-data form and either the externalizable class doesn't exist
- * locally (i.e., obj == null) or readExternal() just threw a
- * CNFException, then the stream is probably in an inconsistent state,
- * since some (or all) of the externalizable data may not have been
- * consumed. Since there's no "correct" action to take in this case,
- * we mimic the behavior of past serialization implementations and
- * blindly hope that the stream is in sync; if it isn't and additional
- * externalizable data remains in the stream, a subsequent read will
- * most likely throw a StreamCorruptedException.
- */
- }
-
- /**
- * Reads (or attempts to skip, if obj is null or is tagged with a
- * ClassNotFoundException) instance data for each serializable class of
- * object in stream, from superclass to subclass. Expects that passHandle
- * is set to obj's handle before this method is called.
- */
- private void readSerialData(Object obj, ObjectStreamClass desc)
- throws IOException
- {
- ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout();
- for (int i = 0; i < slots.length; i++) {
- ObjectStreamClass slotDesc = slots[i].desc;
-
- if (slots[i].hasData) {
- if (obj != null &&
- slotDesc.hasReadObjectMethod() &&
- handles.lookupException(passHandle) == null)
- {
- Object oldContext = curContext;
-
- try {
- curContext = null; //new SerialCallbackContext(obj, slotDesc);
-
- bin.setBlockDataMode(true);
- slotDesc.invokeReadObject(obj, this);
- } catch (ClassNotFoundException ex) {
- /*
- * In most cases, the handle table has already
- * propagated a CNFException to passHandle at this
- * point; this mark call is included to address cases
- * where the custom readObject method has cons'ed and
- * thrown a new CNFException of its own.
- */
- handles.markException(passHandle, ex);
- } finally {
- //curContext.setUsed();
- curContext = oldContext;
- }
-
- /*
- * defaultDataEnd may have been set indirectly by custom
- * readObject() method when calling defaultReadObject() or
- * readFields(); clear it to restore normal read behavior.
- */
- defaultDataEnd = false;
- } else {
- defaultReadFields(obj, slotDesc);
- }
- if (slotDesc.hasWriteObjectData()) {
- skipCustomData();
- } else {
- bin.setBlockDataMode(false);
- }
- } else {
- if (obj != null &&
- slotDesc.hasReadObjectNoDataMethod() &&
- handles.lookupException(passHandle) == null)
- {
- slotDesc.invokeReadObjectNoData(obj);
- }
- }
- }
- }
-
- /**
- * Skips over all block data and objects until TC_ENDBLOCKDATA is
- * encountered.
- */
- private void skipCustomData() throws IOException {
- int oldHandle = passHandle;
- for (;;) {
- if (bin.getBlockDataMode()) {
- bin.skipBlockData();
- bin.setBlockDataMode(false);
- }
- switch (bin.peekByte()) {
- case TC_BLOCKDATA:
- case TC_BLOCKDATALONG:
- bin.setBlockDataMode(true);
- break;
-
- case TC_ENDBLOCKDATA:
- bin.readByte();
- passHandle = oldHandle;
- return;
-
- default:
- readObject0(false);
- break;
- }
- }
- }
-
- /**
- * Reads in values of serializable fields declared by given class
- * descriptor. If obj is non-null, sets field values in obj. Expects that
- * passHandle is set to obj's handle before this method is called.
- */
- private void defaultReadFields(Object obj, ObjectStreamClass desc)
- throws IOException
- {
- // REMIND: is isInstance check necessary?
- Class cl = desc.forClass();
- if (cl != null && obj != null && !cl.isInstance(obj)) {
- throw new ClassCastException();
- }
-
- int primDataSize = desc.getPrimDataSize();
- if (primVals == null || primVals.length < primDataSize) {
- primVals = new byte[primDataSize];
- }
- bin.readFully(primVals, 0, primDataSize, false);
- if (obj != null) {
- desc.setPrimFieldValues(obj, primVals);
- }
-
- int objHandle = passHandle;
- ObjectStreamField[] fields = desc.getFields(false);
- Object[] objVals = new Object[desc.getNumObjFields()];
- int numPrimFields = fields.length - objVals.length;
- for (int i = 0; i < objVals.length; i++) {
- ObjectStreamField f = fields[numPrimFields + i];
- objVals[i] = readObject0(f.isUnshared());
- if (f.getField() != null) {
- handles.markDependency(objHandle, passHandle);
- }
- }
- if (obj != null) {
- desc.setObjFieldValues(obj, objVals);
- }
- passHandle = objHandle;
- }
-
- /**
- * Reads in and returns IOException that caused serialization to abort.
- * All stream state is discarded prior to reading in fatal exception. Sets
- * passHandle to fatal exception's handle.
- */
- private IOException readFatalException() throws IOException {
- if (bin.readByte() != TC_EXCEPTION) {
- throw new InternalError();
- }
- clear();
- return (IOException) readObject0(false);
- }
-
- /**
- * If recursion depth is 0, clears internal data structures; otherwise,
- * throws a StreamCorruptedException. This method is called when a
- * TC_RESET typecode is encountered.
- */
- private void handleReset() throws StreamCorruptedException {
- if (depth > 0) {
- throw new StreamCorruptedException(
- "unexpected reset; recursion depth: " + depth);
- }
- clear();
- }
-
- /**
- * Converts specified span of bytes into float values.
- */
- // REMIND: remove once hotspot inlines Float.intBitsToFloat
- private static native void bytesToFloats(byte[] src, int srcpos,
- float[] dst, int dstpos,
- int nfloats);
-
- /**
- * Converts specified span of bytes into double values.
- */
- // REMIND: remove once hotspot inlines Double.longBitsToDouble
- private static native void bytesToDoubles(byte[] src, int srcpos,
- double[] dst, int dstpos,
- int ndoubles);
-
- /**
- * Returns the first non-null class loader (not counting class loaders of
- * generated reflection implementation classes) up the execution stack, or
- * null if only code from the null class loader is on the stack. This
- * method is also called via reflection by the following RMI-IIOP class:
- *
- * com.sun.corba.se.internal.util.JDKClassLoader
- *
- * This method should not be removed or its signature changed without
- * corresponding modifications to the above class.
- */
- // REMIND: change name to something more accurate?
- private static native ClassLoader latestUserDefinedLoader();
-
- /**
- * Default GetField implementation.
- */
- private class GetFieldImpl extends GetField {
-
- /** class descriptor describing serializable fields */
- private final ObjectStreamClass desc;
- /** primitive field values */
- private final byte[] primVals;
- /** object field values */
- private final Object[] objVals;
- /** object field value handles */
- private final int[] objHandles;
-
- /**
- * Creates GetFieldImpl object for reading fields defined in given
- * class descriptor.
- */
- GetFieldImpl(ObjectStreamClass desc) {
- this.desc = desc;
- primVals = new byte[desc.getPrimDataSize()];
- objVals = new Object[desc.getNumObjFields()];
- objHandles = new int[objVals.length];
- }
-
- public ObjectStreamClass getObjectStreamClass() {
- return desc;
- }
-
- public boolean defaulted(String name) throws IOException {
- return (getFieldOffset(name, null) < 0);
- }
-
- public boolean get(String name, boolean val) throws IOException {
- int off = getFieldOffset(name, Boolean.TYPE);
- return (off >= 0) ? Bits.getBoolean(primVals, off) : val;
- }
-
- public byte get(String name, byte val) throws IOException {
- int off = getFieldOffset(name, Byte.TYPE);
- return (off >= 0) ? primVals[off] : val;
- }
-
- public char get(String name, char val) throws IOException {
- int off = getFieldOffset(name, Character.TYPE);
- return (off >= 0) ? Bits.getChar(primVals, off) : val;
- }
-
- public short get(String name, short val) throws IOException {
- int off = getFieldOffset(name, Short.TYPE);
- return (off >= 0) ? Bits.getShort(primVals, off) : val;
- }
-
- public int get(String name, int val) throws IOException {
- int off = getFieldOffset(name, Integer.TYPE);
- return (off >= 0) ? Bits.getInt(primVals, off) : val;
- }
-
- public float get(String name, float val) throws IOException {
- int off = getFieldOffset(name, Float.TYPE);
- return (off >= 0) ? Bits.getFloat(primVals, off) : val;
- }
-
- public long get(String name, long val) throws IOException {
- int off = getFieldOffset(name, Long.TYPE);
- return (off >= 0) ? Bits.getLong(primVals, off) : val;
- }
-
- public double get(String name, double val) throws IOException {
- int off = getFieldOffset(name, Double.TYPE);
- return (off >= 0) ? Bits.getDouble(primVals, off) : val;
- }
-
- public Object get(String name, Object val) throws IOException {
- int off = getFieldOffset(name, Object.class);
- if (off >= 0) {
- int objHandle = objHandles[off];
- handles.markDependency(passHandle, objHandle);
- return (handles.lookupException(objHandle) == null) ?
- objVals[off] : null;
- } else {
- return val;
- }
- }
-
- /**
- * Reads primitive and object field values from stream.
- */
- void readFields() throws IOException {
- bin.readFully(primVals, 0, primVals.length, false);
-
- int oldHandle = passHandle;
- ObjectStreamField[] fields = desc.getFields(false);
- int numPrimFields = fields.length - objVals.length;
- for (int i = 0; i < objVals.length; i++) {
- objVals[i] =
- readObject0(fields[numPrimFields + i].isUnshared());
- objHandles[i] = passHandle;
- }
- passHandle = oldHandle;
- }
-
- /**
- * Returns offset of field with given name and type. A specified type
- * of null matches all types, Object.class matches all non-primitive
- * types, and any other non-null type matches assignable types only.
- * If no matching field is found in the (incoming) class
- * descriptor but a matching field is present in the associated local
- * class descriptor, returns -1. Throws IllegalArgumentException if
- * neither incoming nor local class descriptor contains a match.
- */
- private int getFieldOffset(String name, Class type) {
- ObjectStreamField field = desc.getField(name, type);
- if (field != null) {
- return field.getOffset();
- } else if (desc.getLocalDesc().getField(name, type) != null) {
- return -1;
- } else {
- throw new IllegalArgumentException("no such field " + name +
- " with type " + type);
- }
- }
- }
-
- /**
- * Prioritized list of callbacks to be performed once object graph has been
- * completely deserialized.
- */
- private static class ValidationList {
-
-
- /**
- * Creates new (empty) ValidationList.
- */
- ValidationList() {
- }
-
- /**
- * Registers callback. Throws InvalidObjectException if callback
- * object is null.
- */
- void register(ObjectInputValidation obj, int priority)
- throws InvalidObjectException
- {
- if (obj == null) {
- throw new InvalidObjectException("null callback");
- }
- throw new InvalidObjectException("Does not work.");
- }
-
- /**
- * Invokes all registered callbacks and clears the callback list.
- * Callbacks with higher priorities are called first; those with equal
- * priorities may be called in any order. If any of the callbacks
- * throws an InvalidObjectException, the callback process is terminated
- * and the exception propagated upwards.
- */
- void doCallbacks() throws InvalidObjectException {
- }
-
- /**
- * Resets the callback list to its initial (empty) state.
- */
- public void clear() {
- }
- }
-
- /**
- * Input stream supporting single-byte peek operations.
- */
- private static class PeekInputStream extends InputStream {
-
- /** underlying stream */
- private final InputStream in;
- /** peeked byte */
- private int peekb = -1;
-
- /**
- * Creates new PeekInputStream on top of given underlying stream.
- */
- PeekInputStream(InputStream in) {
- this.in = in;
- }
-
- /**
- * Peeks at next byte value in stream. Similar to read(), except
- * that it does not consume the read value.
- */
- int peek() throws IOException {
- return (peekb >= 0) ? peekb : (peekb = in.read());
- }
-
- public int read() throws IOException {
- if (peekb >= 0) {
- int v = peekb;
- peekb = -1;
- return v;
- } else {
- return in.read();
- }
- }
-
- public int read(byte[] b, int off, int len) throws IOException {
- if (len == 0) {
- return 0;
- } else if (peekb < 0) {
- return in.read(b, off, len);
- } else {
- b[off++] = (byte) peekb;
- len--;
- peekb = -1;
- int n = in.read(b, off, len);
- return (n >= 0) ? (n + 1) : 1;
- }
- }
-
- void readFully(byte[] b, int off, int len) throws IOException {
- int n = 0;
- while (n < len) {
- int count = read(b, off + n, len - n);
- if (count < 0) {
- throw new EOFException();
- }
- n += count;
- }
- }
-
- public long skip(long n) throws IOException {
- if (n <= 0) {
- return 0;
- }
- int skipped = 0;
- if (peekb >= 0) {
- peekb = -1;
- skipped++;
- n--;
- }
- return skipped + skip(n);
- }
-
- public int available() throws IOException {
- return in.available() + ((peekb >= 0) ? 1 : 0);
- }
-
- public void close() throws IOException {
- in.close();
- }
- }
-
- /**
- * Input stream with two modes: in default mode, inputs data written in the
- * same format as DataOutputStream; in "block data" mode, inputs data
- * bracketed by block data markers (see object serialization specification
- * for details). Buffering depends on block data mode: when in default
- * mode, no data is buffered in advance; when in block data mode, all data
- * for the current data block is read in at once (and buffered).
- */
- private class BlockDataInputStream
- extends InputStream implements DataInput
- {
- /** maximum data block length */
- private static final int MAX_BLOCK_SIZE = 1024;
- /** maximum data block header length */
- private static final int MAX_HEADER_SIZE = 5;
- /** (tunable) length of char buffer (for reading strings) */
- private static final int CHAR_BUF_SIZE = 256;
- /** readBlockHeader() return value indicating header read may block */
- private static final int HEADER_BLOCKED = -2;
-
- /** buffer for reading general/block data */
- private final byte[] buf = new byte[MAX_BLOCK_SIZE];
- /** buffer for reading block data headers */
- private final byte[] hbuf = new byte[MAX_HEADER_SIZE];
- /** char buffer for fast string reads */
- private final char[] cbuf = new char[CHAR_BUF_SIZE];
-
- /** block data mode */
- private boolean blkmode = false;
-
- // block data state fields; values meaningful only when blkmode true
- /** current offset into buf */
- private int pos = 0;
- /** end offset of valid data in buf, or -1 if no more block data */
- private int end = -1;
- /** number of bytes in current block yet to be read from stream */
- private int unread = 0;
-
- /** underlying stream (wrapped in peekable filter stream) */
- private final PeekInputStream in;
- /** loopback stream (for data reads that span data blocks) */
- private final DataInputStream din;
-
- /**
- * Creates new BlockDataInputStream on top of given underlying stream.
- * Block data mode is turned off by default.
- */
- BlockDataInputStream(InputStream in) {
- this.in = new PeekInputStream(in);
- din = new DataInputStream(this);
- }
-
- /**
- * Sets block data mode to the given mode (true == on, false == off)
- * and returns the previous mode value. If the new mode is the same as
- * the old mode, no action is taken. Throws IllegalStateException if
- * block data mode is being switched from on to off while unconsumed
- * block data is still present in the stream.
- */
- boolean setBlockDataMode(boolean newmode) throws IOException {
- if (blkmode == newmode) {
- return blkmode;
- }
- if (newmode) {
- pos = 0;
- end = 0;
- unread = 0;
- } else if (pos < end) {
- throw new IllegalStateException("unread block data");
- }
- blkmode = newmode;
- return !blkmode;
- }
-
- /**
- * Returns true if the stream is currently in block data mode, false
- * otherwise.
- */
- boolean getBlockDataMode() {
- return blkmode;
- }
-
- /**
- * If in block data mode, skips to the end of the current group of data
- * blocks (but does not unset block data mode). If not in block data
- * mode, throws an IllegalStateException.
- */
- void skipBlockData() throws IOException {
- if (!blkmode) {
- throw new IllegalStateException("not in block data mode");
- }
- while (end >= 0) {
- refill();
- }
- }
-
- /**
- * Attempts to read in the next block data header (if any). If
- * canBlock is false and a full header cannot be read without possibly
- * blocking, returns HEADER_BLOCKED, else if the next element in the
- * stream is a block data header, returns the block data length
- * specified by the header, else returns -1.
- */
- private int readBlockHeader(boolean canBlock) throws IOException {
- if (defaultDataEnd) {
- /*
- * Fix for 4360508: stream is currently at the end of a field
- * value block written via default serialization; since there
- * is no terminating TC_ENDBLOCKDATA tag, simulate
- * end-of-custom-data behavior explicitly.
- */
- return -1;
- }
- try {
- for (;;) {
- int avail = canBlock ? Integer.MAX_VALUE : in.available();
- if (avail == 0) {
- return HEADER_BLOCKED;
- }
-
- int tc = in.peek();
- switch (tc) {
- case TC_BLOCKDATA:
- if (avail < 2) {
- return HEADER_BLOCKED;
- }
- in.readFully(hbuf, 0, 2);
- return hbuf[1] & 0xFF;
-
- case TC_BLOCKDATALONG:
- if (avail < 5) {
- return HEADER_BLOCKED;
- }
- in.readFully(hbuf, 0, 5);
- int len = Bits.getInt(hbuf, 1);
- if (len < 0) {
- throw new StreamCorruptedException(
- "illegal block data header length: " +
- len);
- }
- return len;
-
- /*
- * TC_RESETs may occur in between data blocks.
- * Unfortunately, this case must be parsed at a lower
- * level than other typecodes, since primitive data
- * reads may span data blocks separated by a TC_RESET.
- */
- case TC_RESET:
- in.read();
- handleReset();
- break;
-
- default:
- if (tc >= 0 && (tc < TC_BASE || tc > TC_MAX)) {
- throw new StreamCorruptedException(
- String.format("invalid type code: %02X",
- tc));
- }
- return -1;
- }
- }
- } catch (EOFException ex) {
- throw new StreamCorruptedException(
- "unexpected EOF while reading block data header");
- }
- }
-
- /**
- * Refills internal buffer buf with block data. Any data in buf at the
- * time of the call is considered consumed. Sets the pos, end, and
- * unread fields to reflect the new amount of available block data; if
- * the next element in the stream is not a data block, sets pos and
- * unread to 0 and end to -1.
- */
- private void refill() throws IOException {
- try {
- do {
- pos = 0;
- if (unread > 0) {
- int n =
- in.read(buf, 0, Math.min(unread, MAX_BLOCK_SIZE));
- if (n >= 0) {
- end = n;
- unread -= n;
- } else {
- throw new StreamCorruptedException(
- "unexpected EOF in middle of data block");
- }
- } else {
- int n = readBlockHeader(true);
- if (n >= 0) {
- end = 0;
- unread = n;
- } else {
- end = -1;
- unread = 0;
- }
- }
- } while (pos == end);
- } catch (IOException ex) {
- pos = 0;
- end = -1;
- unread = 0;
- throw ex;
- }
- }
-
- /**
- * If in block data mode, returns the number of unconsumed bytes
- * remaining in the current data block. If not in block data mode,
- * throws an IllegalStateException.
- */
- int currentBlockRemaining() {
- if (blkmode) {
- return (end >= 0) ? (end - pos) + unread : 0;
- } else {
- throw new IllegalStateException();
- }
- }
-
- /**
- * Peeks at (but does not consume) and returns the next byte value in
- * the stream, or -1 if the end of the stream/block data (if in block
- * data mode) has been reached.
- */
- int peek() throws IOException {
- if (blkmode) {
- if (pos == end) {
- refill();
- }
- return (end >= 0) ? (buf[pos] & 0xFF) : -1;
- } else {
- return in.peek();
- }
- }
-
- /**
- * Peeks at (but does not consume) and returns the next byte value in
- * the stream, or throws EOFException if end of stream/block data has
- * been reached.
- */
- byte peekByte() throws IOException {
- int val = peek();
- if (val < 0) {
- throw new EOFException();
- }
- return (byte) val;
- }
-
-
- /* ----------------- generic input stream methods ------------------ */
- /*
- * The following methods are equivalent to their counterparts in
- * InputStream, except that they interpret data block boundaries and
- * read the requested data from within data blocks when in block data
- * mode.
- */
-
- public int read() throws IOException {
- if (blkmode) {
- if (pos == end) {
- refill();
- }
- return (end >= 0) ? (buf[pos++] & 0xFF) : -1;
- } else {
- return in.read();
- }
- }
-
- public int read(byte[] b, int off, int len) throws IOException {
- return read(b, off, len, false);
- }
-
- public long skip(long len) throws IOException {
- long remain = len;
- while (remain > 0) {
- if (blkmode) {
- if (pos == end) {
- refill();
- }
- if (end < 0) {
- break;
- }
- int nread = (int) Math.min(remain, end - pos);
- remain -= nread;
- pos += nread;
- } else {
- int nread = (int) Math.min(remain, MAX_BLOCK_SIZE);
- if ((nread = in.read(buf, 0, nread)) < 0) {
- break;
- }
- remain -= nread;
- }
- }
- return len - remain;
- }
-
- public int available() throws IOException {
- if (blkmode) {
- if ((pos == end) && (unread == 0)) {
- int n;
- while ((n = readBlockHeader(false)) == 0) ;
- switch (n) {
- case HEADER_BLOCKED:
- break;
-
- case -1:
- pos = 0;
- end = -1;
- break;
-
- default:
- pos = 0;
- end = 0;
- unread = n;
- break;
- }
- }
- // avoid unnecessary call to in.available() if possible
- int unreadAvail = (unread > 0) ?
- Math.min(in.available(), unread) : 0;
- return (end >= 0) ? (end - pos) + unreadAvail : 0;
- } else {
- return in.available();
- }
- }
-
- public void close() throws IOException {
- if (blkmode) {
- pos = 0;
- end = -1;
- unread = 0;
- }
- in.close();
- }
-
- /**
- * Attempts to read len bytes into byte array b at offset off. Returns
- * the number of bytes read, or -1 if the end of stream/block data has
- * been reached. If copy is true, reads values into an intermediate
- * buffer before copying them to b (to avoid exposing a reference to
- * b).
- */
- int read(byte[] b, int off, int len, boolean copy) throws IOException {
- if (len == 0) {
- return 0;
- } else if (blkmode) {
- if (pos == end) {
- refill();
- }
- if (end < 0) {
- return -1;
- }
- int nread = Math.min(len, end - pos);
- System.arraycopy(buf, pos, b, off, nread);
- pos += nread;
- return nread;
- } else if (copy) {
- int nread = in.read(buf, 0, Math.min(len, MAX_BLOCK_SIZE));
- if (nread > 0) {
- System.arraycopy(buf, 0, b, off, nread);
- }
- return nread;
- } else {
- return in.read(b, off, len);
- }
- }
-
- /* ----------------- primitive data input methods ------------------ */
- /*
- * The following methods are equivalent to their counterparts in
- * DataInputStream, except that they interpret data block boundaries
- * and read the requested data from within data blocks when in block
- * data mode.
- */
-
- public void readFully(byte[] b) throws IOException {
- readFully(b, 0, b.length, false);
- }
-
- public void readFully(byte[] b, int off, int len) throws IOException {
- readFully(b, off, len, false);
- }
-
- public void readFully(byte[] b, int off, int len, boolean copy)
- throws IOException
- {
- while (len > 0) {
- int n = read(b, off, len, copy);
- if (n < 0) {
- throw new EOFException();
- }
- off += n;
- len -= n;
- }
- }
-
- public int skipBytes(int n) throws IOException {
- return din.skipBytes(n);
- }
-
- public boolean readBoolean() throws IOException {
- int v = read();
- if (v < 0) {
- throw new EOFException();
- }
- return (v != 0);
- }
-
- public byte readByte() throws IOException {
- int v = read();
- if (v < 0) {
- throw new EOFException();
- }
- return (byte) v;
- }
-
- public int readUnsignedByte() throws IOException {
- int v = read();
- if (v < 0) {
- throw new EOFException();
- }
- return v;
- }
-
- public char readChar() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 2);
- } else if (end - pos < 2) {
- return din.readChar();
- }
- char v = Bits.getChar(buf, pos);
- pos += 2;
- return v;
- }
-
- public short readShort() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 2);
- } else if (end - pos < 2) {
- return din.readShort();
- }
- short v = Bits.getShort(buf, pos);
- pos += 2;
- return v;
- }
-
- public int readUnsignedShort() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 2);
- } else if (end - pos < 2) {
- return din.readUnsignedShort();
- }
- int v = Bits.getShort(buf, pos) & 0xFFFF;
- pos += 2;
- return v;
- }
-
- public int readInt() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 4);
- } else if (end - pos < 4) {
- return din.readInt();
- }
- int v = Bits.getInt(buf, pos);
- pos += 4;
- return v;
- }
-
- public float readFloat() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 4);
- } else if (end - pos < 4) {
- return din.readFloat();
- }
- float v = Bits.getFloat(buf, pos);
- pos += 4;
- return v;
- }
-
- public long readLong() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 8);
- } else if (end - pos < 8) {
- return din.readLong();
- }
- long v = Bits.getLong(buf, pos);
- pos += 8;
- return v;
- }
-
- public double readDouble() throws IOException {
- if (!blkmode) {
- pos = 0;
- in.readFully(buf, 0, 8);
- } else if (end - pos < 8) {
- return din.readDouble();
- }
- double v = Bits.getDouble(buf, pos);
- pos += 8;
- return v;
- }
-
- public String readUTF() throws IOException {
- return readUTFBody(readUnsignedShort());
- }
-
- public String readLine() throws IOException {
- return din.readLine(); // deprecated, not worth optimizing
- }
-
- /* -------------- primitive data array input methods --------------- */
- /*
- * The following methods read in spans of primitive data values.
- * Though equivalent to calling the corresponding primitive read
- * methods repeatedly, these methods are optimized for reading groups
- * of primitive data values more efficiently.
- */
-
- void readBooleans(boolean[] v, int off, int len) throws IOException {
- int stop, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- int span = Math.min(endoff - off, MAX_BLOCK_SIZE);
- in.readFully(buf, 0, span);
- stop = off + span;
- pos = 0;
- } else if (end - pos < 1) {
- v[off++] = din.readBoolean();
- continue;
- } else {
- stop = Math.min(endoff, off + end - pos);
- }
-
- while (off < stop) {
- v[off++] = Bits.getBoolean(buf, pos++);
- }
- }
- }
-
- void readChars(char[] v, int off, int len) throws IOException {
- int stop, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 1);
- in.readFully(buf, 0, span << 1);
- stop = off + span;
- pos = 0;
- } else if (end - pos < 2) {
- v[off++] = din.readChar();
- continue;
- } else {
- stop = Math.min(endoff, off + ((end - pos) >> 1));
- }
-
- while (off < stop) {
- v[off++] = Bits.getChar(buf, pos);
- pos += 2;
- }
- }
- }
-
- void readShorts(short[] v, int off, int len) throws IOException {
- int stop, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 1);
- in.readFully(buf, 0, span << 1);
- stop = off + span;
- pos = 0;
- } else if (end - pos < 2) {
- v[off++] = din.readShort();
- continue;
- } else {
- stop = Math.min(endoff, off + ((end - pos) >> 1));
- }
-
- while (off < stop) {
- v[off++] = Bits.getShort(buf, pos);
- pos += 2;
- }
- }
- }
-
- void readInts(int[] v, int off, int len) throws IOException {
- int stop, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 2);
- in.readFully(buf, 0, span << 2);
- stop = off + span;
- pos = 0;
- } else if (end - pos < 4) {
- v[off++] = din.readInt();
- continue;
- } else {
- stop = Math.min(endoff, off + ((end - pos) >> 2));
- }
-
- while (off < stop) {
- v[off++] = Bits.getInt(buf, pos);
- pos += 4;
- }
- }
- }
-
- void readFloats(float[] v, int off, int len) throws IOException {
- int span, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 2);
- in.readFully(buf, 0, span << 2);
- pos = 0;
- } else if (end - pos < 4) {
- v[off++] = din.readFloat();
- continue;
- } else {
- span = Math.min(endoff - off, ((end - pos) >> 2));
- }
-
- bytesToFloats(buf, pos, v, off, span);
- off += span;
- pos += span << 2;
- }
- }
-
- void readLongs(long[] v, int off, int len) throws IOException {
- int stop, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 3);
- in.readFully(buf, 0, span << 3);
- stop = off + span;
- pos = 0;
- } else if (end - pos < 8) {
- v[off++] = din.readLong();
- continue;
- } else {
- stop = Math.min(endoff, off + ((end - pos) >> 3));
- }
-
- while (off < stop) {
- v[off++] = Bits.getLong(buf, pos);
- pos += 8;
- }
- }
- }
-
- void readDoubles(double[] v, int off, int len) throws IOException {
- int span, endoff = off + len;
- while (off < endoff) {
- if (!blkmode) {
- span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 3);
- in.readFully(buf, 0, span << 3);
- pos = 0;
- } else if (end - pos < 8) {
- v[off++] = din.readDouble();
- continue;
- } else {
- span = Math.min(endoff - off, ((end - pos) >> 3));
- }
-
- bytesToDoubles(buf, pos, v, off, span);
- off += span;
- pos += span << 3;
- }
- }
-
- /**
- * Reads in string written in "long" UTF format. "Long" UTF format is
- * identical to standard UTF, except that it uses an 8 byte header
- * (instead of the standard 2 bytes) to convey the UTF encoding length.
- */
- String readLongUTF() throws IOException {
- return readUTFBody(readLong());
- }
-
- /**
- * Reads in the "body" (i.e., the UTF representation minus the 2-byte
- * or 8-byte length header) of a UTF encoding, which occupies the next
- * utflen bytes.
- */
- private String readUTFBody(long utflen) throws IOException {
- StringBuilder sbuf = new StringBuilder();
- if (!blkmode) {
- end = pos = 0;
- }
-
- while (utflen > 0) {
- int avail = end - pos;
- if (avail >= 3 || (long) avail == utflen) {
- utflen -= readUTFSpan(sbuf, utflen);
- } else {
- if (blkmode) {
- // near block boundary, read one byte at a time
- utflen -= readUTFChar(sbuf, utflen);
- } else {
- // shift and refill buffer manually
- if (avail > 0) {
- System.arraycopy(buf, pos, buf, 0, avail);
- }
- pos = 0;
- end = (int) Math.min(MAX_BLOCK_SIZE, utflen);
- in.readFully(buf, avail, end - avail);
- }
- }
- }
-
- return sbuf.toString();
- }
-
- /**
- * Reads span of UTF-encoded characters out of internal buffer
- * (starting at offset pos and ending at or before offset end),
- * consuming no more than utflen bytes. Appends read characters to
- * sbuf. Returns the number of bytes consumed.
- */
- private long readUTFSpan(StringBuilder sbuf, long utflen)
- throws IOException
- {
- int cpos = 0;
- int start = pos;
- int avail = Math.min(end - pos, CHAR_BUF_SIZE);
- // stop short of last char unless all of utf bytes in buffer
- int stop = pos + ((utflen > avail) ? avail - 2 : (int) utflen);
- boolean outOfBounds = false;
-
- try {
- while (pos < stop) {
- int b1, b2, b3;
- b1 = buf[pos++] & 0xFF;
- switch (b1 >> 4) {
- case 0:
- case 1:
- case 2:
- case 3:
- case 4:
- case 5:
- case 6:
- case 7: // 1 byte format: 0xxxxxxx
- cbuf[cpos++] = (char) b1;
- break;
-
- case 12:
- case 13: // 2 byte format: 110xxxxx 10xxxxxx
- b2 = buf[pos++];
- if ((b2 & 0xC0) != 0x80) {
- throw new UTFDataFormatException();
- }
- cbuf[cpos++] = (char) (((b1 & 0x1F) << 6) |
- ((b2 & 0x3F) << 0));
- break;
-
- case 14: // 3 byte format: 1110xxxx 10xxxxxx 10xxxxxx
- b3 = buf[pos + 1];
- b2 = buf[pos + 0];
- pos += 2;
- if ((b2 & 0xC0) != 0x80 || (b3 & 0xC0) != 0x80) {
- throw new UTFDataFormatException();
- }
- cbuf[cpos++] = (char) (((b1 & 0x0F) << 12) |
- ((b2 & 0x3F) << 6) |
- ((b3 & 0x3F) << 0));
- break;
-
- default: // 10xx xxxx, 1111 xxxx
- throw new UTFDataFormatException();
- }
- }
- } catch (ArrayIndexOutOfBoundsException ex) {
- outOfBounds = true;
- } finally {
- if (outOfBounds || (pos - start) > utflen) {
- /*
- * Fix for 4450867: if a malformed utf char causes the
- * conversion loop to scan past the expected end of the utf
- * string, only consume the expected number of utf bytes.
- */
- pos = start + (int) utflen;
- throw new UTFDataFormatException();
- }
- }
-
- sbuf.append(cbuf, 0, cpos);
- return pos - start;
- }
-
- /**
- * Reads in single UTF-encoded character one byte at a time, appends
- * the character to sbuf, and returns the number of bytes consumed.
- * This method is used when reading in UTF strings written in block
- * data mode to handle UTF-encoded characters which (potentially)
- * straddle block-data boundaries.
- */
- private int readUTFChar(StringBuilder sbuf, long utflen)
- throws IOException
- {
- int b1, b2, b3;
- b1 = readByte() & 0xFF;
- switch (b1 >> 4) {
- case 0:
- case 1:
- case 2:
- case 3:
- case 4:
- case 5:
- case 6:
- case 7: // 1 byte format: 0xxxxxxx
- sbuf.append((char) b1);
- return 1;
-
- case 12:
- case 13: // 2 byte format: 110xxxxx 10xxxxxx
- if (utflen < 2) {
- throw new UTFDataFormatException();
- }
- b2 = readByte();
- if ((b2 & 0xC0) != 0x80) {
- throw new UTFDataFormatException();
- }
- sbuf.append((char) (((b1 & 0x1F) << 6) |
- ((b2 & 0x3F) << 0)));
- return 2;
-
- case 14: // 3 byte format: 1110xxxx 10xxxxxx 10xxxxxx
- if (utflen < 3) {
- if (utflen == 2) {
- readByte(); // consume remaining byte
- }
- throw new UTFDataFormatException();
- }
- b2 = readByte();
- b3 = readByte();
- if ((b2 & 0xC0) != 0x80 || (b3 & 0xC0) != 0x80) {
- throw new UTFDataFormatException();
- }
- sbuf.append((char) (((b1 & 0x0F) << 12) |
- ((b2 & 0x3F) << 6) |
- ((b3 & 0x3F) << 0)));
- return 3;
-
- default: // 10xx xxxx, 1111 xxxx
- throw new UTFDataFormatException();
- }
- }
- }
-
- /**
- * Unsynchronized table which tracks wire handle to object mappings, as
- * well as ClassNotFoundExceptions associated with deserialized objects.
- * This class implements an exception-propagation algorithm for
- * determining which objects should have ClassNotFoundExceptions associated
- * with them, taking into account cycles and discontinuities (e.g., skipped
- * fields) in the object graph.
- *
- *