| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.commons.proxy2.javassist; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| import javassist.CannotCompileException; |
| import javassist.ClassPool; |
| import javassist.CtClass; |
| import javassist.CtField; |
| import javassist.LoaderClassPath; |
| import javassist.NotFoundException; |
| |
| import org.apache.commons.proxy2.ProxyUtils; |
| import org.apache.commons.proxy2.exception.ObjectProviderException; |
| |
| /** |
| * Some utility methods for dealing with Javassist. This class is not part of the public API! |
| * |
| * @since 1.0 |
| */ |
| final class JavassistUtils |
| { |
| //****************************************************************************************************************** |
| // Fields |
| //****************************************************************************************************************** |
| |
| public static final String DEFAULT_BASE_NAME = "JavassistUtilsGenerated"; |
| private static final AtomicInteger CLASS_NUMBER = new AtomicInteger(0); |
| private static final ClassPool CLASS_POOL = new ClassPool(); |
| private static final Set<ClassLoader> CLASS_LOADERS = new HashSet<ClassLoader>(); |
| |
| //****************************************************************************************************************** |
| // Static Methods |
| //****************************************************************************************************************** |
| |
| static |
| { |
| CLASS_POOL.appendClassPath(new LoaderClassPath(ClassLoader.getSystemClassLoader())); |
| } |
| |
| /** |
| * Adds a field to a class. |
| * |
| * @param fieldType |
| * the field's type |
| * @param fieldName |
| * the field name |
| * @param enclosingClass |
| * the class receiving the new field |
| * @throws CannotCompileException |
| * if a compilation problem occurs |
| */ |
| public static void addField(Class<?> fieldType, String fieldName, CtClass enclosingClass) |
| throws CannotCompileException |
| { |
| enclosingClass.addField(new CtField(resolve(fieldType), fieldName, enclosingClass)); |
| } |
| |
| /** |
| * Adds interfaces to a {@link CtClass} |
| * |
| * @param ctClass |
| * the {@link CtClass} |
| * @param proxyClasses |
| * the interfaces |
| */ |
| public static void addInterfaces(CtClass ctClass, Class<?>[] proxyClasses) |
| { |
| for (int i = 0; i < proxyClasses.length; i++) |
| { |
| Class<?> proxyInterface = proxyClasses[i]; |
| ctClass.addInterface(resolve(proxyInterface)); |
| } |
| } |
| |
| /** |
| * Creates a new {@link CtClass} derived from the Java {@link Class} using the default base name. |
| * |
| * @param superclass |
| * the superclass |
| * @return the new derived {@link CtClass} |
| */ |
| public static CtClass createClass(Class<?> superclass) |
| { |
| return createClass(DEFAULT_BASE_NAME, superclass); |
| } |
| |
| /** |
| * Creates a new {@link CtClass} derived from the Java {@link Class} using the supplied base name. |
| * |
| * @param baseName |
| * the base name |
| * @param superclass |
| * the superclass |
| * @return the new derived {@link CtClass} |
| */ |
| public static synchronized CtClass createClass(String baseName, Class<?> superclass) |
| { |
| return CLASS_POOL.makeClass(baseName + "_" + CLASS_NUMBER.incrementAndGet(), resolve(superclass)); |
| } |
| |
| /** |
| * Finds the {@link CtClass} corresponding to the Java {@link Class} passed in. |
| * |
| * @param clazz |
| * the Java {@link Class} |
| * @return the {@link CtClass} |
| */ |
| public static CtClass resolve(Class<?> clazz) |
| { |
| synchronized (CLASS_LOADERS) |
| { |
| try |
| { |
| final ClassLoader loader = clazz.getClassLoader(); |
| if (loader != null && !CLASS_LOADERS.contains(loader)) |
| { |
| CLASS_LOADERS.add(loader); |
| CLASS_POOL.appendClassPath(new LoaderClassPath(loader)); |
| } |
| return CLASS_POOL.get(ProxyUtils.getJavaClassName(clazz)); |
| } |
| catch (NotFoundException e) |
| { |
| throw new ObjectProviderException("Unable to find class " + clazz.getName() |
| + " in default Javassist class pool.", e); |
| } |
| } |
| } |
| |
| /** |
| * Resolves an array of Java {@link Class}es to an array of their corresponding {@link CtClass}es. |
| * |
| * @param classes |
| * the Java {@link Class}es |
| * @return the corresponding {@link CtClass}es |
| */ |
| public static CtClass[] resolve(Class<?>[] classes) |
| { |
| final CtClass[] ctClasses = new CtClass[classes.length]; |
| for (int i = 0; i < ctClasses.length; ++i) |
| { |
| ctClasses[i] = resolve(classes[i]); |
| } |
| return ctClasses; |
| } |
| |
| private JavassistUtils() |
| { |
| // Hiding constructor in utility class! |
| } |
| } |