non-releases/trunk_before_flattening/src/java/org/apache/cocoon/components/modules/input/SystemPropertyModule.java

/*
 * Copyright 1999-2005 The Apache Software Foundation
 *
 * 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.apache.cocoon.components.modules.input;

import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.thread.ThreadSafe;

import java.util.Map;

/**
 * SystemPropertyModule is an JXPath based InputModule implementation that
 * provides access to system properties.
 * Available system properties are defined by Java's <a
 * href="http://java.sun.com/j2se/1.4.1/docs/api/java/lang/System.html#getProperties()">System.getProperties()</a>.
 *
 * JXPath allows to apply XPath functions to system properties.
 *
 * <p>If there is a security manager, its <code>checkPropertiesAccess</code>
 * method is called with no arguments. This may result in a security exception
 * which is wrapped into a configuration exception and re-thrown.</p>
 *
 * @version $Id$
 */
public class SystemPropertyModule extends AbstractJXPathModule
                                  implements ThreadSafe {

    /**
     * @throws SecurityException if access is denied
     */
    protected Object getContextObject(Configuration modeConf,
                                      Map objectModel) {
        return System.getProperties();
    }
}