com.google.gerrit.rules.PredicateClassLoader Maven / Gradle / Ivy
// Copyright (C) 2012 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.rules;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.SetMultimap;
import com.google.gerrit.extensions.registration.DynamicSet;
import java.util.Collection;
/** Loads the classes for Prolog predicates. */
public class PredicateClassLoader extends ClassLoader {
private final SetMultimap packageClassLoaderMap =
LinkedHashMultimap.create();
public PredicateClassLoader(
final DynamicSet predicateProviders, final ClassLoader parent) {
super(parent);
for (PredicateProvider predicateProvider : predicateProviders) {
for (String pkg : predicateProvider.getPackages()) {
packageClassLoaderMap.put(pkg, predicateProvider.getClass().getClassLoader());
}
}
}
@Override
protected Class findClass(final String className) throws ClassNotFoundException {
final Collection classLoaders =
packageClassLoaderMap.get(getPackageName(className));
for (final ClassLoader cl : classLoaders) {
try {
return Class.forName(className, true, cl);
} catch (ClassNotFoundException e) {
// ignore
}
}
throw new ClassNotFoundException(className);
}
private static String getPackageName(String className) {
final int pos = className.lastIndexOf('.');
if (pos < 0) {
return "";
}
return className.substring(0, pos);
}
}