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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  package org.apache.logging.log4j.taglib;
18  
19  import java.io.IOException;
20  import java.util.Enumeration;
21  
22  import javax.servlet.jsp.JspException;
23  import javax.servlet.jsp.PageContext;
24  import javax.servlet.jsp.tagext.Tag;
25  import javax.servlet.jsp.tagext.TagSupport;
26  
27  /**
28   * This class implements the {@code <log:dump>} tag.
29   *
30   * @since 2.0
31   */
32  public class DumpTag extends TagSupport {
33      private static final long serialVersionUID = 1L;
34  
35      private int scope;
36  
37      public DumpTag() {
38          super();
39          init();
40      }
41  
42      @Override
43      public void release() {
44          super.release();
45          this.init();
46      }
47  
48      private void init() {
49          this.scope = PageContext.PAGE_SCOPE;
50      }
51  
52      public void setScope(final String scope) {
53          this.scope = TagUtils.getScope(scope);
54      }
55  
56      @Override
57      public int doEndTag() throws JspException {
58          try {
59              final Enumeration<String> names = this.pageContext.getAttributeNamesInScope(this.scope);
60              this.pageContext.getOut().write("<dl>");
61              while (names != null && names.hasMoreElements()) {
62                  final String name = names.nextElement();
63                  final Object value = this.pageContext.getAttribute(name, this.scope);
64  
65                  this.pageContext.getOut().write("<dt><code>" + name + "</code></dt>");
66                  this.pageContext.getOut().write("<dd><code>" + value + "</code></dd>");
67              }
68              this.pageContext.getOut().write("</dl>");
69          } catch (final IOException e) {
70              throw new JspException("Could not write scope contents. Cause:  " + e.toString(), e);
71          }
72  
73          return Tag.EVAL_PAGE;
74      }
75  }