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Diffstat (limited to 'src/com/sun/org/apache/bcel/internal/util/ClassLoader.java')
| -rw-r--r-- | src/com/sun/org/apache/bcel/internal/util/ClassLoader.java | 224 |
1 files changed, 0 insertions, 224 deletions
diff --git a/src/com/sun/org/apache/bcel/internal/util/ClassLoader.java b/src/com/sun/org/apache/bcel/internal/util/ClassLoader.java deleted file mode 100644 index 1be5b3b..0000000 --- a/src/com/sun/org/apache/bcel/internal/util/ClassLoader.java +++ /dev/null @@ -1,224 +0,0 @@ -/* - * reserved comment block - * DO NOT REMOVE OR ALTER! - */ -package com.sun.org.apache.bcel.internal.util; - -/* ==================================================================== - * The Apache Software License, Version 1.1 - * - * Copyright (c) 2001 The Apache Software Foundation. All rights - * reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * - * 3. The end-user documentation included with the redistribution, - * if any, must include the following acknowledgment: - * "This product includes software developed by the - * Apache Software Foundation (http://www.apache.org/)." - * Alternately, this acknowledgment may appear in the software itself, - * if and wherever such third-party acknowledgments normally appear. - * - * 4. The names "Apache" and "Apache Software Foundation" and - * "Apache BCEL" must not be used to endorse or promote products - * derived from this software without prior written permission. For - * written permission, please contact apache@apache.org. - * - * 5. Products derived from this software may not be called "Apache", - * "Apache BCEL", nor may "Apache" appear in their name, without - * prior written permission of the Apache Software Foundation. - * - * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED - * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR - * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF - * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND - * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, - * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT - * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * ==================================================================== - * - * This software consists of voluntary contributions made by many - * individuals on behalf of the Apache Software Foundation. For more - * information on the Apache Software Foundation, please see - * <http://www.apache.org/>. - */ - -import java.util.Hashtable; -import java.io.*; -import com.sun.org.apache.bcel.internal.*; -import com.sun.org.apache.bcel.internal.classfile.*; - -/** - * <p>Drop in replacement for the standard class loader of the JVM. You can use it - * in conjunction with the JavaWrapper to dynamically modify/create classes - * as they're requested.</p> - * - * <p>This class loader recognizes special requests in a distinct - * format, i.e., when the name of the requested class contains with - * "$$BCEL$$" it calls the createClass() method with that name - * (everything bevor the $$BCEL$$ is considered to be the package - * name. You can subclass the class loader and override that - * method. "Normal" classes class can be modified by overriding the - * modifyClass() method which is called just before defineClass().</p> - * - * <p>There may be a number of packages where you have to use the default - * class loader (which may also be faster). You can define the set of packages - * where to use the system class loader in the constructor. The default value contains - * "java.", "sun.", "javax."</p> - * - * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A> - * @see JavaWrapper - * @see ClassPath - */ -public class ClassLoader extends java.lang.ClassLoader { - private Hashtable classes = new Hashtable(); // Hashtable is synchronized thus thread-safe - private String[] ignored_packages = { - "java.", "javax.", "sun." - }; - private Repository repository = SyntheticRepository.getInstance(); - private java.lang.ClassLoader deferTo = ClassLoader.getSystemClassLoader(); - - public ClassLoader() { - } - - public ClassLoader(java.lang.ClassLoader deferTo) { - this.deferTo = deferTo; - this.repository = new ClassLoaderRepository(deferTo); - } - - /** @param ignored_packages classes contained in these packages will be loaded - * with the system class loader - */ - public ClassLoader(String[] ignored_packages) { - addIgnoredPkgs(ignored_packages); - } - - public ClassLoader(java.lang.ClassLoader deferTo, String [] ignored_packages) { - this.deferTo = deferTo; - this.repository = new ClassLoaderRepository(deferTo); - - addIgnoredPkgs(ignored_packages); - } - - private void addIgnoredPkgs(String[] ignored_packages) { - String[] new_p = new String[ignored_packages.length + this.ignored_packages.length]; - - System.arraycopy(this.ignored_packages, 0, new_p, 0, this.ignored_packages.length); - System.arraycopy(ignored_packages, 0, new_p, this.ignored_packages.length, - ignored_packages.length); - - this.ignored_packages = new_p; - } - - protected Class loadClass(String class_name, boolean resolve) - throws ClassNotFoundException - { - Class cl = null; - - /* First try: lookup hash table. - */ - if((cl=(Class)classes.get(class_name)) == null) { - /* Second try: Load system class using system class loader. You better - * don't mess around with them. - */ - for(int i=0; i < ignored_packages.length; i++) { - if(class_name.startsWith(ignored_packages[i])) { - cl = deferTo.loadClass(class_name); - break; - } - } - - if(cl == null) { - JavaClass clazz = null; - - /* Third try: Special request? - */ - if(class_name.indexOf("$$BCEL$$") >= 0) - clazz = createClass(class_name); - else { // Fourth try: Load classes via repository - if ((clazz = repository.loadClass(class_name)) != null) { - clazz = modifyClass(clazz); - } - else - throw new ClassNotFoundException(class_name); - } - - if(clazz != null) { - byte[] bytes = clazz.getBytes(); - cl = defineClass(class_name, bytes, 0, bytes.length); - } else // Fourth try: Use default class loader - cl = Class.forName(class_name); - } - - if(resolve) - resolveClass(cl); - } - - classes.put(class_name, cl); - - return cl; - } - - /** Override this method if you want to alter a class before it gets actually - * loaded. Does nothing by default. - */ - protected JavaClass modifyClass(JavaClass clazz) { - return clazz; - } - - /** - * Override this method to create you own classes on the fly. The - * name contains the special token $$BCEL$$. Everything before that - * token is consddered to be a package name. You can encode you own - * arguments into the subsequent string. You must regard however not - * to use any "illegal" characters, i.e., characters that may not - * appear in a Java class name too<br> - * - * The default implementation interprets the string as a encoded compressed - * Java class, unpacks and decodes it with the Utility.decode() method, and - * parses the resulting byte array and returns the resulting JavaClass object. - * - * @param class_name compressed byte code with "$$BCEL$$" in it - */ - protected JavaClass createClass(String class_name) { - int index = class_name.indexOf("$$BCEL$$"); - String real_name = class_name.substring(index + 8); - - JavaClass clazz = null; - try { - byte[] bytes = Utility.decode(real_name, true); - ClassParser parser = new ClassParser(new ByteArrayInputStream(bytes), "foo"); - - clazz = parser.parse(); - } catch(Throwable e) { - e.printStackTrace(); - return null; - } - - // Adapt the class name to the passed value - ConstantPool cp = clazz.getConstantPool(); - - ConstantClass cl = (ConstantClass)cp.getConstant(clazz.getClassNameIndex(), - Constants.CONSTANT_Class); - ConstantUtf8 name = (ConstantUtf8)cp.getConstant(cl.getNameIndex(), - Constants.CONSTANT_Utf8); - name.setBytes(class_name.replace('.', '/')); - - return clazz; - } -} |