001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements. See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache license, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License. You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the license for the specific language governing permissions and
015     * limitations under the license.
016     */
017    package org.apache.logging.log4j.taglib;
018    
019    import java.io.IOException;
020    import java.util.Enumeration;
021    
022    import javax.servlet.jsp.JspException;
023    import javax.servlet.jsp.PageContext;
024    import javax.servlet.jsp.tagext.Tag;
025    import javax.servlet.jsp.tagext.TagSupport;
026    
027    /**
028     * This class implements the {@code <log:dump>} tag.
029     *
030     * @since 2.0
031     */
032    public class DumpTag extends TagSupport {
033        private static final long serialVersionUID = 1L;
034    
035        private int scope;
036    
037        public DumpTag() {
038            super();
039            init();
040        }
041    
042        @Override
043        public void release() {
044            super.release();
045            this.init();
046        }
047    
048        private void init() {
049            this.scope = PageContext.PAGE_SCOPE;
050        }
051    
052        public void setScope(final String scope) {
053            this.scope = TagUtils.getScope(scope);
054        }
055    
056        @Override
057        public int doEndTag() throws JspException {
058            try {
059                final Enumeration<String> names = this.pageContext.getAttributeNamesInScope(this.scope);
060                this.pageContext.getOut().write("<dl>");
061                while (names != null && names.hasMoreElements()) {
062                    final String name = names.nextElement();
063                    final Object value = this.pageContext.getAttribute(name, this.scope);
064    
065                    this.pageContext.getOut().write("<dt><code>" + name + "</code></dt>");
066                    this.pageContext.getOut().write("<dd><code>" + value + "</code></dd>");
067                }
068                this.pageContext.getOut().write("</dl>");
069            } catch (final IOException e) {
070                throw new JspException("Could not write scope contents. Cause:  " + e.toString(), e);
071            }
072    
073            return Tag.EVAL_PAGE;
074        }
075    }