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 javax.servlet.jsp.JspException;
020    import javax.servlet.jsp.PageContext;
021    import javax.servlet.jsp.tagext.Tag;
022    import javax.servlet.jsp.tagext.TagSupport;
023    import java.io.IOException;
024    import java.util.Enumeration;
025    
026    /**
027     * This class implements the {@code <log:dump>} tag.
028     *
029     * @since 2.0
030     */
031    public class DumpTag extends TagSupport {
032        private static final long serialVersionUID = 1L;
033    
034        private int scope;
035    
036        public DumpTag() {
037            super();
038            init();
039        }
040    
041        @Override
042        public void release() {
043            super.release();
044            this.init();
045        }
046    
047        private void init() {
048            this.scope = PageContext.PAGE_SCOPE;
049        }
050    
051        public void setScope(String scope) {
052            this.scope = TagUtils.getScope(scope);
053        }
054    
055        @Override
056        public int doEndTag() throws JspException {
057            try {
058                Enumeration<String> names = this.pageContext.getAttributeNamesInScope(this.scope);
059                this.pageContext.getOut().write("<dl>");
060                while (names != null && names.hasMoreElements()) {
061                    String name = names.nextElement();
062                    Object value = this.pageContext.getAttribute(name, this.scope);
063    
064                    this.pageContext.getOut().write("<dt><code>" + name + "</code></dt>");
065                    this.pageContext.getOut().write("<dd><code>" + value + "</code></dd>");
066                }
067                this.pageContext.getOut().write("</dl>");
068            } catch (IOException e) {
069                throw new JspException("Could not write scope contents. Cause:  " + e.toString(), e);
070            }
071    
072            return Tag.EVAL_PAGE;
073        }
074    }