/*

  * Copyright (c) 1996, 2010, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package java.lang.reflect;

 import java.lang.annotation.Annotation;

 import static java.lang.reflect.Method.fromPrimitive;

 import static java.lang.reflect.Method.getAccess;

 import static java.lang.reflect.Method.getParameterTypes;

 import org.apidesign.bck2brwsr.core.JavaScriptBody;

 import org.apidesign.bck2brwsr.emul.reflect.TypeProvider;

 /**

  * {@code Constructor} provides information about, and access to, a single

  * constructor for a class.

  *

  * <p>{@code Constructor} permits widening conversions to occur when matching the

  * actual parameters to newInstance() with the underlying

  * constructor's formal parameters, but throws an

  * {@code IllegalArgumentException} if a narrowing conversion would occur.

  *

  * @param <T> the class in which the constructor is declared

  *

  * @see Member

  * @see java.lang.Class

  * @see java.lang.Class#getConstructors()

  * @see java.lang.Class#getConstructor(Class[])

  * @see java.lang.Class#getDeclaredConstructors()

  *

  * @author      Kenneth Russell

  * @author      Nakul Saraiya

  */

 public final

     class Constructor<T> extends AccessibleObject implements

                                                     GenericDeclaration,

                                                     Member {

     private final Class<T> clazz;

     private final Object data;

     private final String sig;

     /**

      * Package-private constructor used by ReflectAccess to enable

      * instantiation of these objects in Java code from the java.lang

      * package via sun.reflect.LangReflectAccess.

      */

     Constructor(Class<T> declaringClass, Object data, String sig)

     {

         this.clazz = declaringClass;

         this.data = data;

         this.sig = sig;

     }

     /**

      * Package-private routine (exposed to java.lang.Class via

      * ReflectAccess) which returns a copy of this Constructor. The copy's

      * "root" field points to this Constructor.

      */

     Constructor<T> copy() {

         return this;

     }

     /**

      * Returns the {@code Class} object representing the class that declares

      * the constructor represented by this {@code Constructor} object.

      */

     public Class<T> getDeclaringClass() {

         return clazz;

     }

     /**

      * Returns the name of this constructor, as a string.  This is

      * the binary name of the constructor's declaring class.

      */

     public String getName() {

         return getDeclaringClass().getName();

     }

     /**

      * Returns the Java language modifiers for the constructor

      * represented by this {@code Constructor} object, as an integer. The

      * {@code Modifier} class should be used to decode the modifiers.

      *

      * @see Modifier

      */

     public int getModifiers() {

         return getAccess(data);

     }

     /**

      * Returns an array of {@code TypeVariable} objects that represent the

      * type variables declared by the generic declaration represented by this

      * {@code GenericDeclaration} object, in declaration order.  Returns an

      * array of length 0 if the underlying generic declaration declares no type

      * variables.

      *

      * @return an array of {@code TypeVariable} objects that represent

      *     the type variables declared by this generic declaration

      * @throws GenericSignatureFormatError if the generic

      *     signature of this generic declaration does not conform to

      *     the format specified in

      *     <cite>The Java&trade; Virtual Machine Specification</cite>

      * @since 1.5

      */

     public TypeVariable<Constructor<T>>[] getTypeParameters() {

         return TypeProvider.getDefault().getTypeParameters(this);

     }

     /**

      * Returns an array of {@code Class} objects that represent the formal

      * parameter types, in declaration order, of the constructor

      * represented by this {@code Constructor} object.  Returns an array of

      * length 0 if the underlying constructor takes no parameters.

      *

      * @return the parameter types for the constructor this object

      * represents

      */

     public Class<?>[] getParameterTypes() {

         return Method.getParameterTypes(sig);

     }

     /**

      * Returns an array of {@code Type} objects that represent the formal

      * parameter types, in declaration order, of the method represented by

      * this {@code Constructor} object. Returns an array of length 0 if the

      * underlying method takes no parameters.

      *

      * <p>If a formal parameter type is a parameterized type,

      * the {@code Type} object returned for it must accurately reflect

      * the actual type parameters used in the source code.

      *

      * <p>If a formal parameter type is a type variable or a parameterized

      * type, it is created. Otherwise, it is resolved.

      *

      * @return an array of {@code Type}s that represent the formal

      *     parameter types of the underlying method, in declaration order

      * @throws GenericSignatureFormatError

      *     if the generic method signature does not conform to the format

      *     specified in

      *     <cite>The Java&trade; Virtual Machine Specification</cite>

      * @throws TypeNotPresentException if any of the parameter

      *     types of the underlying method refers to a non-existent type

      *     declaration

      * @throws MalformedParameterizedTypeException if any of

      *     the underlying method's parameter types refer to a parameterized

      *     type that cannot be instantiated for any reason

      * @since 1.5

      */

     public Type[] getGenericParameterTypes() {

         return TypeProvider.getDefault().getGenericParameterTypes(this);

     }

     /**

      * Returns an array of {@code Class} objects that represent the types

      * of exceptions declared to be thrown by the underlying constructor

      * represented by this {@code Constructor} object.  Returns an array of

      * length 0 if the constructor declares no exceptions in its {@code throws} clause.

      *

      * @return the exception types declared as being thrown by the

      * constructor this object represents

      */

     public Class<?>[] getExceptionTypes() {

         throw new UnsupportedOperationException();

     }

     /**

      * Returns an array of {@code Type} objects that represent the

      * exceptions declared to be thrown by this {@code Constructor} object.

      * Returns an array of length 0 if the underlying method declares

      * no exceptions in its {@code throws} clause.

      *

      * <p>If an exception type is a type variable or a parameterized

      * type, it is created. Otherwise, it is resolved.

      *

      * @return an array of Types that represent the exception types

      *     thrown by the underlying method

      * @throws GenericSignatureFormatError

      *     if the generic method signature does not conform to the format

      *     specified in

      *     <cite>The Java&trade; Virtual Machine Specification</cite>

      * @throws TypeNotPresentException if the underlying method's

      *     {@code throws} clause refers to a non-existent type declaration

      * @throws MalformedParameterizedTypeException if

      *     the underlying method's {@code throws} clause refers to a

      *     parameterized type that cannot be instantiated for any reason

      * @since 1.5

      */

       public Type[] getGenericExceptionTypes() {

           return TypeProvider.getDefault().getGenericExceptionTypes(this);

       }

     /**

      * Compares this {@code Constructor} against the specified object.

      * Returns true if the objects are the same.  Two {@code Constructor} objects are

      * the same if they were declared by the same class and have the

      * same formal parameter types.

      */

     public boolean equals(Object obj) {

         if (obj instanceof Constructor) {

             Constructor other = (Constructor)obj;

             return data == other.data;

         }

         return false;

     }

     /**

      * Returns a hashcode for this {@code Constructor}. The hashcode is

      * the same as the hashcode for the underlying constructor's

      * declaring class name.

      */

     public int hashCode() {

         return getDeclaringClass().getName().hashCode();

     }

     /**

      * Returns a string describing this {@code Constructor}.  The string is

      * formatted as the constructor access modifiers, if any,

      * followed by the fully-qualified name of the declaring class,

      * followed by a parenthesized, comma-separated list of the

      * constructor's formal parameter types.  For example:

      * <pre>

      *    public java.util.Hashtable(int,float)

      * </pre>

      *

      * <p>The only possible modifiers for constructors are the access

      * modifiers {@code public}, {@code protected} or

      * {@code private}.  Only one of these may appear, or none if the

      * constructor has default (package) access.

      */

     public String toString() {

         try {

             StringBuffer sb = new StringBuffer();

             int mod = getModifiers() & Modifier.constructorModifiers();

             if (mod != 0) {

                 sb.append(Modifier.toString(mod) + " ");

             }

             sb.append(Field.getTypeName(getDeclaringClass()));

             sb.append("(");

             Class<?>[] params = getParameterTypes(); // avoid clone

             for (int j = 0; j < params.length; j++) {

                 sb.append(Field.getTypeName(params[j]));

                 if (j < (params.length - 1))

                     sb.append(",");

             }

             sb.append(")");

             /*

             Class<?>[] exceptions = exceptionTypes; // avoid clone

             if (exceptions.length > 0) {

                 sb.append(" throws ");

                 for (int k = 0; k < exceptions.length; k++) {

                     sb.append(exceptions[k].getName());

                     if (k < (exceptions.length - 1))

                         sb.append(",");

                 }

             }

             */

             return sb.toString();

         } catch (Exception e) {

             return "<" + e + ">";

         }

     }

     /**

      * Returns a string describing this {@code Constructor},

      * including type parameters.  The string is formatted as the

      * constructor access modifiers, if any, followed by an

      * angle-bracketed comma separated list of the constructor's type

      * parameters, if any, followed by the fully-qualified name of the

      * declaring class, followed by a parenthesized, comma-separated

      * list of the constructor's generic formal parameter types.

      *

      * If this constructor was declared to take a variable number of

      * arguments, instead of denoting the last parameter as

      * "<tt><i>Type</i>[]</tt>", it is denoted as

      * "<tt><i>Type</i>...</tt>".

      *

      * A space is used to separate access modifiers from one another

      * and from the type parameters or return type.  If there are no

      * type parameters, the type parameter list is elided; if the type

      * parameter list is present, a space separates the list from the

      * class name.  If the constructor is declared to throw

      * exceptions, the parameter list is followed by a space, followed

      * by the word "{@code throws}" followed by a

      * comma-separated list of the thrown exception types.

      *

      * <p>The only possible modifiers for constructors are the access

      * modifiers {@code public}, {@code protected} or

      * {@code private}.  Only one of these may appear, or none if the

      * constructor has default (package) access.

      *

      * @return a string describing this {@code Constructor},

      * include type parameters

      *

      * @since 1.5

      */

     public String toGenericString() {

         try {

             StringBuilder sb = new StringBuilder();

             int mod = getModifiers() & Modifier.constructorModifiers();

             if (mod != 0) {

                 sb.append(Modifier.toString(mod) + " ");

             }

             TypeVariable<?>[] typeparms = getTypeParameters();

             if (typeparms.length > 0) {

                 boolean first = true;

                 sb.append("<");

                 for(TypeVariable<?> typeparm: typeparms) {

                     if (!first)

                         sb.append(",");

                     // Class objects can't occur here; no need to test

                     // and call Class.getName().

                     sb.append(typeparm.toString());

                     first = false;

                 }

                 sb.append("> ");

             }

             sb.append(Field.getTypeName(getDeclaringClass()));

             sb.append("(");

             Type[] params = getGenericParameterTypes();

             for (int j = 0; j < params.length; j++) {

                 String param = (params[j] instanceof Class<?>)?

                     Field.getTypeName((Class<?>)params[j]):

                     (params[j].toString());

                 if (isVarArgs() && (j == params.length - 1)) // replace T[] with T...

                     param = param.replaceFirst("\\[\\]$", "...");

                 sb.append(param);

                 if (j < (params.length - 1))

                     sb.append(",");

             }

             sb.append(")");

             Type[] exceptions = getGenericExceptionTypes();

             if (exceptions.length > 0) {

                 sb.append(" throws ");

                 for (int k = 0; k < exceptions.length; k++) {

                     sb.append((exceptions[k] instanceof Class)?

                               ((Class<?>)exceptions[k]).getName():

                               exceptions[k].toString());

                     if (k < (exceptions.length - 1))

                         sb.append(",");

                 }

             }

             return sb.toString();

         } catch (Exception e) {

             return "<" + e + ">";

         }

     }

     /**

      * Uses the constructor represented by this {@code Constructor} object to

      * create and initialize a new instance of the constructor's

      * declaring class, with the specified initialization parameters.

      * Individual parameters are automatically unwrapped to match

      * primitive formal parameters, and both primitive and reference

      * parameters are subject to method invocation conversions as necessary.

      *

      * <p>If the number of formal parameters required by the underlying constructor

      * is 0, the supplied {@code initargs} array may be of length 0 or null.

      *

      * <p>If the constructor's declaring class is an inner class in a

      * non-static context, the first argument to the constructor needs

      * to be the enclosing instance; see section 15.9.3 of

      * <cite>The Java&trade; Language Specification</cite>.

      *

      * <p>If the required access and argument checks succeed and the

      * instantiation will proceed, the constructor's declaring class

      * is initialized if it has not already been initialized.

      *

      * <p>If the constructor completes normally, returns the newly

      * created and initialized instance.

      *

      * @param initargs array of objects to be passed as arguments to

      * the constructor call; values of primitive types are wrapped in

      * a wrapper object of the appropriate type (e.g. a {@code float}

      * in a {@link java.lang.Float Float})

      *

      * @return a new object created by calling the constructor

      * this object represents

      *

      * @exception IllegalAccessException    if this {@code Constructor} object

      *              is enforcing Java language access control and the underlying

      *              constructor is inaccessible.

      * @exception IllegalArgumentException  if the number of actual

      *              and formal parameters differ; if an unwrapping

      *              conversion for primitive arguments fails; or if,

      *              after possible unwrapping, a parameter value

      *              cannot be converted to the corresponding formal

      *              parameter type by a method invocation conversion; if

      *              this constructor pertains to an enum type.

      * @exception InstantiationException    if the class that declares the

      *              underlying constructor represents an abstract class.

      * @exception InvocationTargetException if the underlying constructor

      *              throws an exception.

      * @exception ExceptionInInitializerError if the initialization provoked

      *              by this method fails.

      */

     public T newInstance(Object ... initargs)

         throws InstantiationException, IllegalAccessException,

                IllegalArgumentException, InvocationTargetException

     {

         Class[] types = getParameterTypes();

         if (types.length != initargs.length) {

             throw new IllegalArgumentException("Types len " + types.length + " args: " + initargs.length);

         } else {

             initargs = initargs.clone();

             for (int i = 0; i < types.length; i++) {

                 Class c = types[i];

                 if (c.isPrimitive() && initargs[i] != null) {

                     initargs[i] = Method.toPrimitive(initargs[i]);

                 }

             }

         }

         return (T) newInstance0(this.getDeclaringClass(), "cons__" + sig, initargs);

     }

     @JavaScriptBody(args = { "self", "sig", "args" }, body =

           "\nvar c = self.cnstr;"

         + "\nvar inst = c();"

         + "\nc[sig].apply(inst, args);"

         + "\nreturn inst;"

     )

     private static native Object newInstance0(Class<?> self, String sig, Object[] args);

     /**

      * Returns {@code true} if this constructor was declared to take

      * a variable number of arguments; returns {@code false}

      * otherwise.

      *

      * @return {@code true} if an only if this constructor was declared to

      * take a variable number of arguments.

      * @since 1.5

      */

     public boolean isVarArgs() {

         return (getModifiers() & Modifier.VARARGS) != 0;

     }

     /**

      * Returns {@code true} if this constructor is a synthetic

      * constructor; returns {@code false} otherwise.

      *

      * @return true if and only if this constructor is a synthetic

      * constructor as defined by

      * <cite>The Java&trade; Language Specification</cite>.

      * @since 1.5

      */

     public boolean isSynthetic() {

         return Modifier.isSynthetic(getModifiers());

     }

     /**

      * @throws NullPointerException {@inheritDoc}

      * @since 1.5

      */

     public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {

         if (annotationClass == null)

             throw new NullPointerException();

         return null; // XXX (T) declaredAnnotations().get(annotationClass);

     }

     /**

      * @since 1.5

      */

     public Annotation[] getDeclaredAnnotations()  {

         return new Annotation[0]; // XXX AnnotationParser.toArray(declaredAnnotations());

     }

     /**

      * Returns an array of arrays that represent the annotations on the formal

      * parameters, in declaration order, of the method represented by

      * this {@code Constructor} object. (Returns an array of length zero if the

      * underlying method is parameterless.  If the method has one or more

      * parameters, a nested array of length zero is returned for each parameter

      * with no annotations.) The annotation objects contained in the returned

      * arrays are serializable.  The caller of this method is free to modify

      * the returned arrays; it will have no effect on the arrays returned to

      * other callers.

      *

      * @return an array of arrays that represent the annotations on the formal

      *    parameters, in declaration order, of the method represented by this

      *    Constructor object

      * @since 1.5

      */

     public Annotation[][] getParameterAnnotations() {

 //        int numParameters = parameterTypes.length;

 //        if (parameterAnnotations == null)

 //            return new Annotation[numParameters][0];

         return new Annotation[0][0]; // XXX

 /*

         Annotation[][] result = AnnotationParser.parseParameterAnnotations(

             parameterAnnotations,

             sun.misc.SharedSecrets.getJavaLangAccess().

                 getConstantPool(getDeclaringClass()),

             getDeclaringClass());

         if (result.length != numParameters) {

             Class<?> declaringClass = getDeclaringClass();

             if (declaringClass.isEnum() ||

                 declaringClass.isAnonymousClass() ||

                 declaringClass.isLocalClass() )

                 ; // Can't do reliable parameter counting

             else {

                 if (!declaringClass.isMemberClass() || // top-level

                     // Check for the enclosing instance parameter for

                     // non-static member classes

                     (declaringClass.isMemberClass() &&

                      ((declaringClass.getModifiers() & Modifier.STATIC) == 0)  &&

                      result.length + 1 != numParameters) ) {

                     throw new AnnotationFormatError(

                               "Parameter annotations don't match number of parameters");

                 }

             }

         }

         return result;

         */

     }

 }