MemorySensitiveClassPathRepository.java
/*
* 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
*
* https://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.bcel.util;
import java.lang.ref.SoftReference;
import java.util.HashMap;
import java.util.Map;
import org.apache.bcel.classfile.JavaClass;
/**
* This repository is used in situations where a Class is created outside the realm of a ClassLoader. Classes are loaded
* from the file systems using the paths specified in the given class path. By default, this is the value returned by
* ClassPath.getClassPath(). This repository holds onto classes with SoftReferences, and will reload as needed, in cases
* where memory sizes are important.
*
* @see org.apache.bcel.Repository
*/
public class MemorySensitiveClassPathRepository extends AbstractClassPathRepository {
private final Map<String, SoftReference<JavaClass>> loadedClasses = new HashMap<>(); // CLASSNAME X JAVACLASS
public MemorySensitiveClassPathRepository(final ClassPath path) {
super(path);
}
/**
* Clear all entries from cache.
*/
@Override
public void clear() {
loadedClasses.clear();
}
/**
* Find an already defined (cached) JavaClass object by name.
*/
@Override
public JavaClass findClass(final String className) {
final SoftReference<JavaClass> ref = loadedClasses.get(className);
return ref == null ? null : ref.get();
}
/**
* Remove class from repository
*/
@Override
public void removeClass(final JavaClass clazz) {
loadedClasses.remove(clazz.getClassName());
}
/**
* Store a new JavaClass instance into this Repository.
*/
@Override
public void storeClass(final JavaClass clazz) {
// Not calling super.storeClass because this subclass maintains the mapping.
loadedClasses.put(clazz.getClassName(), new SoftReference<>(clazz));
clazz.setRepository(this);
}
}