| /* InstrumentationImpl.java -- GNU implementation of |
| java.lang.instrument.Instrumentation |
| Copyright (C) 2005 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.lang; |
| |
| import java.lang.instrument.Instrumentation; |
| import java.lang.instrument.ClassFileTransformer; |
| import java.lang.instrument.ClassDefinition; |
| import java.lang.instrument.UnmodifiableClassException; |
| import java.lang.instrument.IllegalClassFormatException; |
| |
| import java.security.ProtectionDomain; |
| |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| |
| /** |
| * An Instrumentation object has transformers that will |
| * be called each time a class is defined or redefined. |
| * The object is given to a <code>premain</code> function |
| * that is called before the <code>main</code> function. |
| * |
| * @author Nicolas Geoffray (nicolas.geoffray@menlina.com) |
| * @since 1.5 |
| */ |
| public final class InstrumentationImpl implements Instrumentation |
| { |
| |
| /* List of transformers */ |
| /* FIXME[GENERICS]: Should be ClassFileTransformer list */ |
| private ArrayList transformers = new ArrayList(); |
| |
| |
| private InstrumentationImpl() |
| { |
| } |
| |
| /** |
| * Adds a <code>ClassFileTransformer</class> object |
| * to the instrumentation. Each time a class is defined |
| * or redefined, the <code>transform</code> method of the |
| * <code>transformer</code> object is called. |
| * |
| * @param transformer the transformer to add |
| * @throws NullPointerException if transformer is null |
| */ |
| public void addTransformer(ClassFileTransformer transformer) |
| { |
| if (transformer == null) |
| throw new NullPointerException(); |
| synchronized(transformers) |
| { |
| transformers.add(transformer); |
| } |
| } |
| |
| /** |
| * Removes the given transformer from the set of transformers |
| * this Instrumentation object has. |
| * |
| * @param transformer the transformer to remove |
| * @return true if the transformer was found and removed, false if |
| * the transformer was not found |
| * @throws NullPointerException if transformer is null |
| */ |
| public boolean removeTransformer(ClassFileTransformer transformer) |
| { |
| if (transformer == null) |
| throw new NullPointerException(); |
| |
| boolean result; |
| synchronized (transformers) |
| { |
| result = transformers.remove(transformer); |
| } |
| return result; |
| } |
| |
| /** |
| * Returns if the current JVM supports class redefinition |
| * |
| * @return true if the current JVM supports class redefinition |
| */ |
| public boolean isRedefineClassesSupported() |
| { |
| return VMInstrumentationImpl.isRedefineClassesSupported(); |
| } |
| |
| /** |
| * Redefine classes present in the definitions array, with |
| * the corresponding class files. |
| * |
| * @param definitions an array of classes to redefine |
| * |
| * @throws ClassNotFoundException if a class cannot be found |
| * @throws UnmodifiableClassException if a class cannot be modified |
| * @throws UnsupportedOperationException if the JVM does not support |
| * redefinition or the redefinition made unsupported changes |
| * @throws ClassFormatError if a class file is not valid |
| * @throws NoClassDefFoundError if a class name is not equal to the name |
| * in the class file specified |
| * @throws UnsupportedClassVersionError if the class file version numbers |
| * are unsupported |
| * @throws ClassCircularityError if circularity occured with the new |
| * classes |
| * @throws LinkageError if a linkage error occurs |
| * @throws NullPointerException if the definitions array is null, or any |
| * of its element |
| * |
| * @see isRedefineClassesSupported() |
| * @see addTransformer(java.lang.instrument.ClassFileTransformer) |
| * @see ClassFileTransformer |
| */ |
| public void redefineClasses(ClassDefinition[] definitions) |
| throws ClassNotFoundException, |
| UnmodifiableClassException |
| { |
| if (!isRedefineClassesSupported()) |
| throw new UnsupportedOperationException(); |
| |
| VMInstrumentationImpl.redefineClasses(this, definitions); |
| } |
| |
| |
| /** |
| * Get all the classes loaded by the JVM. |
| * |
| * @return an array containing all the classes loaded by the JVM. The array |
| * is empty if no class is loaded. |
| */ |
| public Class[] getAllLoadedClasses() |
| { |
| return VMInstrumentationImpl.getAllLoadedClasses(); |
| } |
| |
| /** |
| * Get all the classes loaded by a given class loader |
| * |
| * @param loader the loader |
| * |
| * @return an array containing all the classes loaded by the given loader. |
| * The array is empty if no class was loaded by the loader. |
| */ |
| public Class[] getInitiatedClasses(ClassLoader loader) |
| { |
| return VMInstrumentationImpl.getInitiatedClasses(loader); |
| } |
| |
| /** |
| * Get the size of an object. |
| * |
| * @param objectToSize the object |
| * @return the size of the object |
| * @throws NullPointerException if objectToSize is null. |
| */ |
| public long getObjectSize(Object objectToSize) |
| { |
| // We alleviate the VM work |
| if (objectToSize == null) |
| throw new NullPointerException(); |
| return VMInstrumentationImpl.getObjectSize(objectToSize); |
| } |
| |
| /** |
| * Called by the VM or redefineClasses to call each transformer |
| * |
| * @param loader the loader of the class |
| * @param className the name of the class with packages separated with "/" |
| * @param classBeingRedefined the class being redefined if it's the case, |
| * null otherwise |
| * @param protectionDomain the protection domain of the class being defined |
| * or redefined |
| * @param classfileBuffer the input byte buffer in class file format |
| * |
| * @return the new class file |
| */ |
| /* FIXME[GENERICS]: Should be Class<?> */ |
| public byte[] callTransformers(ClassLoader loader, String className, |
| Class classBeingRedefined, ProtectionDomain protectionDomain, |
| byte[] classfileBuffer) |
| { |
| byte[] newBuffer = null; |
| byte[] oldBuffer = classfileBuffer; |
| ClassFileTransformer current; |
| synchronized (transformers) |
| { |
| Iterator i = transformers.iterator(); |
| while (i.hasNext()) |
| { |
| /* FIXME[GENERICS]: Remove cast */ |
| current = (ClassFileTransformer) i.next(); |
| try |
| { |
| newBuffer = current.transform(loader, className, |
| classBeingRedefined, protectionDomain, oldBuffer); |
| } |
| catch (IllegalClassFormatException ignored) |
| { |
| //IGNORED |
| } |
| if (newBuffer != null) |
| oldBuffer = newBuffer; |
| } |
| } |
| return oldBuffer; |
| } |
| } |