001/* 
002    Licensed to the Apache Software Foundation (ASF) under one
003    or more contributor license agreements.  See the NOTICE file
004    distributed with this work for additional information
005    regarding copyright ownership.  The ASF licenses this file
006    to you under the Apache License, Version 2.0 (the
007    "License"); you may not use this file except in compliance
008    with the License.  You may obtain a copy of the License at
009
010       http://www.apache.org/licenses/LICENSE-2.0
011
012    Unless required by applicable law or agreed to in writing,
013    software distributed under the License is distributed on an
014    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015    KIND, either express or implied.  See the License for the
016    specific language governing permissions and limitations
017    under the License.  
018 */
019package org.apache.wiki.ui;
020
021import org.apache.wiki.api.core.Command;
022import org.apache.wiki.api.core.ContextEnum;
023
024import java.security.Permission;
025
026/**
027 * <p>Defines Commands for redirections to off-site special pages. RedirectCommands do not have associated permissions; the
028 * {@link #requiredPermission()} method will always return <code>null</code>. When combined with a supplied String url,
029 * the {@link #getTarget()} method will return a String, the {@link #getURLPattern()} method will return the supplied target URL,
030 * and {@link #getJSP()} method will return the "cleansed" URL.</p>
031 *
032 * @since 2.4.22
033 */
034public final class RedirectCommand extends AbstractCommand {
035
036    public static final Command REDIRECT = new RedirectCommand( ContextEnum.REDIRECT, null );
037
038    /**
039     * Constructs a new Command with a specified wiki context, URL pattern, type, and content template. The WikiPage for this action is
040     * initialized to <code>null</code>.
041     *
042     * @param currentContext the current context.
043     * @param target the target of the command
044     * @throws IllegalArgumentException if the request content, URL pattern, or type is <code>null</code>
045     */
046    private RedirectCommand( final ContextEnum currentContext, final String target ) {
047        this( currentContext.getRequestContext(), currentContext.getUrlPattern(), currentContext.getContentTemplate(), target );
048    }
049
050    /**
051     *
052     * @param requestContext the request context
053     * @param urlPattern the URL pattern
054     * @param contentTemplate the content template; may be <code>null</code>
055     * @param target the target of the command
056     * @throws IllegalArgumentException if the request content, URL pattern, or type is <code>null</code>
057     */
058    private RedirectCommand( final String requestContext, final String urlPattern, final String contentTemplate, final String target ) {
059        super( requestContext, urlPattern, contentTemplate, target );
060    }
061    
062    /**
063     * Creates and returns a targeted Command by combining a URL (as String) with this Command. The supplied <code>target</code>
064     * object must be non-<code>null</code> and of type String. The URL passed to the constructor is actually an URL pattern, but it
065     * will be converted to a JSP page if it is a partial URL. If it is a full URL (beginning with <code>http://</code> or
066     * <code>https://</code>), it will be "passed through" without conversion, and the URL pattern will be <code>null</code>.
067     *
068     * @param target the object to combine
069     * @throws IllegalArgumentException if the target is not of the correct type
070     */
071    public Command targetedCommand( final Object target ) {
072        if ( !( target instanceof String ) ) {
073            throw new IllegalArgumentException( "Target must non-null and of type String." );
074        }
075        return new RedirectCommand( getRequestContext(), ( String )target, getContentTemplate(), ( String )target );
076    }
077    
078    /**
079     * @see org.apache.wiki.api.core.Command#getName()
080     */
081    public String getName() {
082        final Object target = getTarget();
083        if ( target == null ) {
084            return getJSPFriendlyName();
085        }
086        return target.toString();
087    }
088
089    /**
090     * No-op; always returns <code>null</code>.
091     *
092     * @see org.apache.wiki.api.core.Command#requiredPermission()
093     */
094    public Permission requiredPermission() {
095        return null;
096    }
097
098}