diff -r 6799184bf769 -r 5c990ed353e9 rt/emul/compact/src/main/java/sun/invoke/anon/AnonymousClassLoader.java --- a/rt/emul/compact/src/main/java/sun/invoke/anon/AnonymousClassLoader.java Sun Aug 10 05:56:32 2014 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,230 +0,0 @@ -/* - * Copyright (c) 2008, 2012, 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 sun.invoke.anon; - -import java.io.IOException; -import java.lang.reflect.InvocationTargetException; -import java.lang.reflect.Method; -import sun.misc.IOUtils; - -/** - * Anonymous class loader. Will load any valid classfile, producing - * a {@link Class} metaobject, without installing that class in the - * system dictionary. Therefore, {@link Class#forName(String)} will never - * produce a reference to an anonymous class. - *

- * The access permissions of the anonymous class are borrowed from - * a host class. The new class behaves as if it were an - * inner class of the host class. It can access the host's private - * members, if the creator of the class loader has permission to - * do so (or to create accessible reflective objects). - *

- * When the anonymous class is loaded, elements of its constant pool - * can be patched to new values. This provides a hook to pre-resolve - * named classes in the constant pool to other classes, including - * anonymous ones. Also, string constants can be pre-resolved to - * any reference. (The verifier treats non-string, non-class reference - * constants as plain objects.) - *

- * Why include the patching function? It makes some use cases much easier. - * Second, the constant pool needed some internal patching anyway, - * to anonymize the loaded class itself. Finally, if you are going - * to use this seriously, you'll want to build anonymous classes - * on top of pre-existing anonymous classes, and that requires patching. - * - *

%%% TO-DO: - *

- * - * @author jrose - * @author Remi Forax - * @see - * http://blogs.sun.com/jrose/entry/anonymous_classes_in_the_vm - */ - -public class AnonymousClassLoader { - final Class hostClass; - - // Privileged constructor. - private AnonymousClassLoader(Class hostClass) { - this.hostClass = hostClass; - } - - public static AnonymousClassLoader make(sun.misc.Unsafe unsafe, Class hostClass) { - if (unsafe == null) throw new NullPointerException(); - return new AnonymousClassLoader(hostClass); - } - - public Class loadClass(byte[] classFile) { - if (defineAnonymousClass == null) { - // no JVM support; try to fake an approximation - try { - return fakeLoadClass(new ConstantPoolParser(classFile).createPatch()); - } catch (InvalidConstantPoolFormatException ee) { - throw new IllegalArgumentException(ee); - } - } - return loadClass(classFile, null); - } - - public Class loadClass(ConstantPoolPatch classPatch) { - if (defineAnonymousClass == null) { - // no JVM support; try to fake an approximation - return fakeLoadClass(classPatch); - } - Object[] patches = classPatch.patchArray; - // Convert class names (this late in the game) - // to use slash '/' instead of dot '.'. - // Java likes dots, but the JVM likes slashes. - for (int i = 0; i < patches.length; i++) { - Object value = patches[i]; - if (value != null) { - byte tag = classPatch.getTag(i); - switch (tag) { - case ConstantPoolVisitor.CONSTANT_Class: - if (value instanceof String) { - if (patches == classPatch.patchArray) - patches = patches.clone(); - patches[i] = ((String)value).replace('.', '/'); - } - break; - case ConstantPoolVisitor.CONSTANT_Fieldref: - case ConstantPoolVisitor.CONSTANT_Methodref: - case ConstantPoolVisitor.CONSTANT_InterfaceMethodref: - case ConstantPoolVisitor.CONSTANT_NameAndType: - // When/if the JVM supports these patches, - // we'll probably need to reformat them also. - // Meanwhile, let the class loader create the error. - break; - } - } - } - return loadClass(classPatch.outer.classFile, classPatch.patchArray); - } - - private Class loadClass(byte[] classFile, Object[] patchArray) { - try { - return (Class) - defineAnonymousClass.invoke(unsafe, - hostClass, classFile, patchArray); - } catch (Exception ex) { - throwReflectedException(ex); - throw new RuntimeException("error loading into "+hostClass, ex); - } - } - - private static void throwReflectedException(Exception ex) { - if (ex instanceof InvocationTargetException) { - Throwable tex = ((InvocationTargetException)ex).getTargetException(); - if (tex instanceof Error) - throw (Error) tex; - ex = (Exception) tex; - } - if (ex instanceof RuntimeException) { - throw (RuntimeException) ex; - } - } - - private Class fakeLoadClass(ConstantPoolPatch classPatch) { - // Implementation: - // 1. Make up a new name nobody has used yet. - // 2. Inspect the tail-header of the class to find the this_class index. - // 3. Patch the CONSTANT_Class for this_class to the new name. - // 4. Add other CP entries required by (e.g.) string patches. - // 5. Flatten Class constants down to their names, making sure that - // the host class loader can pick them up again accurately. - // 6. Generate the edited class file bytes. - // - // Potential limitations: - // * The class won't be truly anonymous, and may interfere with others. - // * Flattened class constants might not work, because of loader issues. - // * Pseudo-string constants will not flatten down to real strings. - // * Method handles will (of course) fail to flatten to linkage strings. - if (true) throw new UnsupportedOperationException("NYI"); - Object[] cpArray; - try { - cpArray = classPatch.getOriginalCP(); - } catch (InvalidConstantPoolFormatException ex) { - throw new RuntimeException(ex); - } - int thisClassIndex = classPatch.getParser().getThisClassIndex(); - String thisClassName = (String) cpArray[thisClassIndex]; - synchronized (AnonymousClassLoader.class) { - thisClassName = thisClassName+"\\|"+(++fakeNameCounter); - } - classPatch.putUTF8(thisClassIndex, thisClassName); - byte[] classFile = null; - return unsafe.defineClass(null, classFile, 0, classFile.length, - hostClass.getClassLoader(), - hostClass.getProtectionDomain()); - } - private static int fakeNameCounter = 99999; - - // ignore two warnings on this line: - private static sun.misc.Unsafe unsafe = sun.misc.Unsafe.getUnsafe(); - // preceding line requires that this class be on the boot class path - - static private final Method defineAnonymousClass; - static { - Method dac = null; - Class unsafeClass = unsafe.getClass(); - try { - dac = unsafeClass.getMethod("defineAnonymousClass", - Class.class, - byte[].class, - Object[].class); - } catch (Exception ee) { - dac = null; - } - defineAnonymousClass = dac; - } - - private static void noJVMSupport() { - throw new UnsupportedOperationException("no JVM support for anonymous classes"); - } - - - private static native Class loadClassInternal(Class hostClass, - byte[] classFile, - Object[] patchArray); - - public static byte[] readClassFile(Class templateClass) throws IOException { - String templateName = templateClass.getName(); - int lastDot = templateName.lastIndexOf('.'); - java.net.URL url = templateClass.getResource(templateName.substring(lastDot+1)+".class"); - java.net.URLConnection connection = url.openConnection(); - int contentLength = connection.getContentLength(); - if (contentLength < 0) - throw new IOException("invalid content length "+contentLength); - - return IOUtils.readFully(connection.getInputStream(), contentLength, true); - } -}