    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.tags;
    020
    021import org.apache.logging.log4j.LogManager;
    022import org.apache.logging.log4j.Logger;
    023import org.apache.wiki.api.core.Context;
    024import org.apache.wiki.util.TextUtil;
    025
    026import jakarta.servlet.jsp.JspException;
    027import jakarta.servlet.jsp.PageContext;
    028import jakarta.servlet.jsp.tagext.TagSupport;
    029import jakarta.servlet.jsp.tagext.TryCatchFinally;
    030
    031
    032/**
    033 *  Base class for JSPWiki tags.  You do not necessarily have to derive from this class, since this does some initialization.
    034 *  <P>
    035 *  This tag is only useful if you're having an "empty" tag, with no body content.
    036 *
    037 *  @since 2.0
    038 */
    039public abstract class WikiTagBase extends TagSupport implements TryCatchFinally {
    040
    041    private static final long serialVersionUID = -1409836349293777141L;
    042    private static final Logger LOG = LogManager.getLogger( WikiTagBase.class );
    043
    044    protected Context m_wikiContext;
    045
    046    /**
    047     * This method calls the parent setPageContext() but it also provides a way for a tag to initialize itself before
    048     * any of the setXXX() methods are called.
    049     */
    050    @Override
    051    public void setPageContext( final PageContext arg0 ) {
    052        super.setPageContext( arg0 );
    053        initTag();
    054    }
    055
    056    /**
    057     *  This method is called when the tag is encountered within a new request, but before the setXXX() methods are called.
    058     *  The default implementation does nothing.
    059     *  @since 2.3.92
    060     */
    061    public void initTag() {
    062        m_wikiContext = null;
    063    }
    064
    065    public int doStartTag() throws JspException {
    066        try {
    067            m_wikiContext = ( Context )pageContext.getAttribute( Context.ATTR_CONTEXT, PageContext.REQUEST_SCOPE );
    068            if( m_wikiContext == null ) {
    069                throw new JspException("WikiContext may not be NULL - serious internal problem!");
    070            }
    071
    072            return doWikiStartTag();
    073        } catch( final Exception e ) {
    074            LOG.error( "Tag failed", e );
    075            throw new JspException( "Tag failed, check logs: "+e.getMessage() );
    076        }
    077    }
    078
    079    /**
    080     *  This method is allowed to do pretty much whatever he wants.
    081     *  We then catch all mistakes.
    082     */
    083    public abstract int doWikiStartTag() throws Exception;
    084
    085    public int doEndTag() throws JspException {
    086        return EVAL_PAGE;
    087    }
    088
    089    @Override
    090    public void doCatch( final Throwable th ) throws Throwable {
    091        LOG.error( th.getMessage(), th );
    092    }
    093
    094    public void doFinally()
    095    {
    096        m_wikiContext = null;
    097    }
    098
    099    public void setId( final String id)
    100    {
    101        super.setId( TextUtil.replaceEntities( id ) );
    102    }
    103
    104}