| /* |
| * Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| package com.sun.xml.internal.bind.v2.runtime.reflect.opt; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.lang.ref.WeakReference; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.WeakHashMap; |
| import java.util.logging.Level; |
| import java.util.logging.Logger; |
| |
| import com.sun.xml.internal.bind.Util; |
| |
| /** |
| * A {@link ClassLoader} used to "inject" optimized accessor classes |
| * into the VM. |
| * |
| * <p> |
| * Its parent class loader needs to be set to the one that can see the user |
| * class. |
| * |
| * @author Kohsuke Kawaguchi |
| */ |
| final class Injector { |
| |
| /** |
| * {@link Injector}s keyed by their parent {@link ClassLoader}. |
| * |
| * We only need one injector per one user class loader. |
| */ |
| private static final Map<ClassLoader,WeakReference<Injector>> injectors = |
| Collections.synchronizedMap(new WeakHashMap<ClassLoader,WeakReference<Injector>>()); |
| |
| private static final Logger logger = Util.getClassLogger(); |
| |
| /** |
| * Injects a new class into the given class loader. |
| * |
| * @return null |
| * if it fails to inject. |
| */ |
| static Class inject( ClassLoader cl, String className, byte[] image ) { |
| Injector injector = get(cl); |
| if(injector!=null) |
| return injector.inject(className,image); |
| else |
| return null; |
| } |
| |
| /** |
| * Returns the already injected class, or null. |
| */ |
| static Class find( ClassLoader cl, String className ) { |
| Injector injector = get(cl); |
| if(injector!=null) |
| return injector.find(className); |
| else |
| return null; |
| } |
| |
| /** |
| * Gets or creates an {@link Injector} for the given class loader. |
| * |
| * @return null |
| * if it fails. |
| */ |
| private static Injector get(ClassLoader cl) { |
| Injector injector = null; |
| WeakReference<Injector> wr = injectors.get(cl); |
| if(wr!=null) |
| injector = wr.get(); |
| if(injector==null) |
| try { |
| injectors.put(cl,new WeakReference<Injector>(injector = new Injector(cl))); |
| } catch (SecurityException e) { |
| logger.log(Level.FINE,"Unable to set up a back-door for the injector",e); |
| return null; |
| } |
| return injector; |
| } |
| |
| /** |
| * Injected classes keyed by their names. |
| */ |
| private final Map<String,Class> classes = new HashMap<String,Class>(); |
| |
| private final ClassLoader parent; |
| |
| private static final Method defineClass; |
| private static final Method resolveClass; |
| |
| static { |
| try { |
| defineClass = ClassLoader.class.getDeclaredMethod("defineClass",String.class,byte[].class,Integer.TYPE,Integer.TYPE); |
| resolveClass = ClassLoader.class.getDeclaredMethod("resolveClass",Class.class); |
| } catch (NoSuchMethodException e) { |
| // impossible |
| throw new NoSuchMethodError(e.getMessage()); |
| } |
| AccessController.doPrivileged(new PrivilegedAction<Void>() { |
| public Void run() { |
| // TODO: check security implication |
| // do these setAccessible allow anyone to call these methods freely?s |
| defineClass.setAccessible(true); |
| resolveClass.setAccessible(true); |
| return null; |
| } |
| }); |
| } |
| |
| private Injector(ClassLoader parent) { |
| this.parent = parent; |
| assert parent!=null; |
| } |
| |
| |
| private synchronized Class inject(String className, byte[] image) { |
| Class c = classes.get(className); |
| if(c==null) { |
| // we need to inject a class into the |
| try { |
| c = (Class)defineClass.invoke(parent,className.replace('/','.'),image,0,image.length); |
| resolveClass.invoke(parent,c); |
| } catch (IllegalAccessException e) { |
| logger.log(Level.FINE,"Unable to inject "+className,e); |
| return null; |
| } catch (InvocationTargetException e) { |
| logger.log(Level.FINE,"Unable to inject "+className,e); |
| return null; |
| } catch (SecurityException e) { |
| logger.log(Level.FINE,"Unable to inject "+className,e); |
| return null; |
| } catch (LinkageError e) { |
| logger.log(Level.FINE,"Unable to inject "+className,e); |
| return null; |
| } |
| classes.put(className,c); |
| } |
| return c; |
| } |
| |
| private synchronized Class find(String className) { |
| return classes.get(className); |
| } |
| } |