editlinktag.java

wiki建站资源 java编写的 很好用

/* 
    JSPWiki - a JSP-based WikiWiki clone.

    Copyright (C) 2001-2002 Janne Jalkanen ([e-mail])

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 2.1 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.ecyrd.jspwiki.tags;

import java.io.IOException;
import javax.servlet.jsp.JspWriter;

import com.ecyrd.jspwiki.WikiContext;
import com.ecyrd.jspwiki.WikiEngine;
import com.ecyrd.jspwiki.WikiPage;

/**
 *  Writes an edit link.  Body of the link becomes the link text.
 *  <P><B>Attributes</B></P>
 *  <UL>
 *    <LI>page - Page name to refer to.  Default is the current page.
 *    <LI>format - Format, either "anchor" or "url".
 *    <LI>version - Version number of the page to refer to.  Possible values
 *        are "this", meaning the version of the current page; or a version
 *        number.  Default is always to point at the latest version of the page.
 *  </UL>
 *
 *  @author Janne Jalkanen
 *  @since 2.0
 */
public class EditLinkTag
    extends WikiLinkTag
{
    public String m_version = null;

    public void setVersion( String vers )
    {
        m_version = vers;
    }

    public final int doWikiStartTag()
        throws IOException
    {
        WikiEngine engine   = m_wikiContext.getEngine();
        WikiPage   page     = null;
        String     versionString = "";
        String     pageName = null;
        
        //
        //  Determine the page and the link.
        //
        if( m_pageName == null )
        {
            page = m_wikiContext.getPage();
            if( page == null )
            {
                // You can't call this on the page itself anyways.
                return SKIP_BODY;
            }
            else
            {
                pageName = page.getName();
            }
        }
        else
        {
            pageName = m_pageName;
        }

        //
        //  Determine the latest version, if the version attribute is "this".
        //
        if( m_version != null )
        {
            if( "this".equalsIgnoreCase(m_version) )
            {
                if( page == null )
                {
                    // No page, so go fetch according to page name.
                    page = engine.getPage( m_pageName );
                }
                
                if( page != null )
                {
                    versionString = "version="+page.getVersion();
                }
            }
            else
            {
                versionString = "version="+m_version;
            }
        }

        //
        //  Finally, print out the correct link, according to what
        //  user commanded.
        //
        JspWriter out = pageContext.getOut();

        switch( m_format )
        {
          case ANCHOR:
            out.print("<a href=\""+m_wikiContext.getURL(WikiContext.EDIT,pageName, versionString)+"\">");
            break;

          case URL:
            out.print( m_wikiContext.getURL(WikiContext.EDIT,pageName,versionString) );
            break;
        }

        return EVAL_BODY_INCLUDE;
    }
}