com.google.gerrit.server.plugins.DelegatingClassLoader Maven / Gradle / Ivy
// Copyright (C) 2016 The Android Open Source Project
//
// 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 com.google.gerrit.server.plugins;
import com.google.common.io.ByteStreams;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;
public class DelegatingClassLoader extends ClassLoader {
private final ClassLoader target;
public DelegatingClassLoader(ClassLoader parent, ClassLoader target) {
super(parent);
this.target = target;
}
@Override
public Class findClass(String name) throws ClassNotFoundException {
String path = name.replace('.', '/') + ".class";
try (InputStream resource = target.getResourceAsStream(path)) {
if (resource != null) {
try {
byte[] bytes = ByteStreams.toByteArray(resource);
return defineClass(name, bytes, 0, bytes.length);
} catch (IOException e) {
// throws ClassNotFoundException later
}
}
} catch (IOException e) {
// throws ClassNotFoundException later
}
throw new ClassNotFoundException(name);
}
@Override
public URL getResource(String name) {
URL rtn = getParent().getResource(name);
if (rtn == null) {
rtn = target.getResource(name);
}
return rtn;
}
@Override
public Enumeration getResources(String name) throws IOException {
Enumeration rtn = getParent().getResources(name);
if (rtn == null) {
rtn = target.getResources(name);
}
return rtn;
}
@Override
public InputStream getResourceAsStream(String name) {
InputStream rtn = getParent().getResourceAsStream(name);
if (rtn == null) {
rtn = target.getResourceAsStream(name);
}
return rtn;
}
}