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     */
019    package org.apache.wiki.tags;
020    
021    import java.io.IOException;
022    
023    import javax.servlet.jsp.JspWriter;
024    
025    import org.apache.wiki.InternalWikiException;
026    import org.apache.wiki.WikiContext;
027    import org.apache.wiki.WikiPage;
028    
029    /**
030     *  Writes a comment link.  Body of the link becomes the link text.
031     *  <P><B>Attributes</B></P>
032     *  <UL>
033     *    <LI>page - Page name to refer to.  Default is the current page.
034     *    <LI>format - Format, either "anchor" or "url".
035     *  </UL>
036     *
037     *  @since 2.0
038     */
039    public class CommentLinkTag
040        extends WikiLinkTag
041    {
042        private static final long serialVersionUID = 0L;
043        
044        /**
045         *  {@inheritDoc}
046         */
047        @Override
048        public final int doWikiStartTag()
049            throws IOException
050        {
051            WikiPage   page     = null;
052            String     pageName = null;
053            
054            //
055            //  Determine the page and the link.
056            //
057            if( m_pageName == null )
058            {
059                page = m_wikiContext.getPage();
060                if( page == null )
061                {
062                    // You can't call this on the page itself anyways.
063                    return SKIP_BODY;
064                }
065    
066                pageName = page.getName();
067            }
068            else
069            {
070                pageName = m_pageName;
071            }
072    
073            //
074            //  Finally, print out the correct link, according to what
075            //  user commanded.
076            //
077            JspWriter out = pageContext.getOut();
078    
079            switch( m_format )
080            {
081                case ANCHOR:
082                    out.print("<a href=\""+getCommentURL(pageName)+"\">");
083                    break;
084    
085                case URL:
086                    out.print( getCommentURL(pageName) );
087                    break;
088                    
089                default:
090                    throw new InternalWikiException("Impossible format "+m_format);
091                
092            }
093    
094            return EVAL_BODY_INCLUDE;
095        }
096    
097        private String getCommentURL( String pageName )
098        {
099            return m_wikiContext.getURL(WikiContext.COMMENT, pageName);
100        }
101    
102    }