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/*
* Copyright 2003-2007 the original author or authors.
*
* Licensed 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.codehaus.groovy.runtime.metaclass;
import org.codehaus.groovy.runtime.Reflector;
import java.security.ProtectionDomain;
import java.util.HashMap;
import java.util.Map;
/**
* Reflector creation helper. This class is used to define the Refloctor classes.
* For each ClassLoader such a loader will be created by MetaClass.
* Special about this loader is, that it knows the classes form the
* Groovy Runtime. The Reflector class is resolved in different ways: During
* the definition of a class Reflector will resolve to the Reflector class of
* the runtime, even if there is another Reflector class in the parent loader.
* After the new class is defined Reflector will resolve like other Groovy
* classes. This loader is able to resolve all Groovy classes even if the
* parent does not know them, but the parent serves first (Reflector during a
* class definition is different).
*
* @author Jochen Theodorou
* @version $Revision$
*/
public class ReflectorLoader extends ClassLoader {
private boolean inDefine = false;
private final Map loadedClasses = new HashMap();
private final ClassLoader delegatationLoader;
private static final String REFLECTOR = Reflector.class.getName();
/**
* Tries to find a Groovy class.
*
* @return the class if found
* @throws ClassNotFoundException if not found
*/
protected Class findClass(String name) throws ClassNotFoundException {
if (delegatationLoader==null) return super.findClass(name);
return delegatationLoader.loadClass(name);
}
/**
* Loads a class per name. Unlike a normal loadClass this version
* behaves different during a class definition. In that case it
* checks if the class we want to load is Reflector and returns
* class if the check is successful. If it is not during a class
* definition it just calls the super class version of loadClass.
*
* @param name of the class to load
* @param resolve is true if the class should be resolved
* @see Reflector
* @see ClassLoader#loadClass(String, boolean)
*/
protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException {
if (inDefine) {
if (name.equals(REFLECTOR)) return Reflector.class;
}
return super.loadClass(name, resolve);
}
/**
* helper method to define Reflector classes.
* @param name of the Reflector
* @param bytecode the bytecode
* @param domain the protection domain
* @return the generated class
*/
public synchronized Class defineClass(String name, byte[] bytecode, ProtectionDomain domain) {
inDefine = true;
Class c = defineClass(name, bytecode, 0, bytecode.length, domain);
loadedClasses.put(name,c);
resolveClass(c);
inDefine = false;
return c;
}
/**
* creates a ReflectorLoader.
* @param parent the parent loader. This should never be null!
*/
public ReflectorLoader(ClassLoader parent) {
super(parent);
delegatationLoader = getClass().getClassLoader();
}
/**
* try to load one of the defined Reflector classes by name.
* @param name of the Reflector class
* @return the Reflector class if defined else null.
*/
public synchronized Class getLoadedClass(String name) {
return (Class)loadedClasses.get(name);
}
static String getReflectorName(Class theClass) {
String className = theClass.getName();
if (className.startsWith("java.")) {
String packagePrefix = "gjdk.";
String name = packagePrefix + className + "_GroovyReflector";
if (theClass.isArray()) {
Class clazz = theClass;
name = packagePrefix;
int level = 0;
while (clazz.isArray()) {
clazz = clazz.getComponentType();
level++;
}
String componentName = clazz.getName();
name = packagePrefix + componentName + "_GroovyReflectorArray";
if (level>1) name += level;
}
return name;
}
else {
String name = className.replace('$','_') + "_GroovyReflector";
if (theClass.isArray()) {
Class clazz = theClass;
int level = 0;
while (clazz.isArray()) {
clazz = clazz.getComponentType();
level++;
}
String componentName = clazz.getName();
name = componentName.replace('$','_') + "_GroovyReflectorArray";
if (level>1) name += level;
}
return name;
}
}
}