org.jboss.modules.security.LoadedPermissionFactory Maven / Gradle / Ivy
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* JBoss, Home of Professional Open Source.
* Copyright 2014 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* 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.jboss.modules.security;
import java.security.Permission;
/**
* A permission factory which instantiates a permission with the given class name.
*
* @author David M. Lloyd
*/
public final class LoadedPermissionFactory implements PermissionFactory {
private final ClassLoader classLoader;
private final String className;
private final String targetName;
private final String permissionActions;
private volatile Permission instance = UninitializedPermission.INSTANCE;
/**
* Construct a new instance.
*
* @param classLoader the class loader from which the permission should be loaded
* @param className the name of the permission class
* @param targetName the name to pass to the permission class constructor or {@code null} for none
* @param permissionActions the action list to pass to the permission class constructor or {@code null} for none
*/
public LoadedPermissionFactory(final ClassLoader classLoader, final String className, final String targetName, final String permissionActions) {
if (className == null) {
throw new IllegalArgumentException("className is null");
}
this.classLoader = classLoader;
this.className = className;
this.targetName = targetName;
this.permissionActions = permissionActions;
}
public Permission construct() {
if (instance != UninitializedPermission.INSTANCE) {
return instance;
}
synchronized (this) {
if (instance != UninitializedPermission.INSTANCE) {
return instance;
}
try {
final Class permissionClass = classLoader.loadClass(className).asSubclass(Permission.class);
return instance = PermissionFactory.constructFromClass(permissionClass, targetName, permissionActions);
} catch (Throwable t) {
instance = null;
return null;
}
}
}
}