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1   /*
2   * Copyright 2004 The Apache Software Foundation
3   *
4   * Licensed under the Apache License, Version 2.0 (the "License");
5   * you may not use this file except in compliance with the License.
6   * You may obtain a copy of the License at
7   *
8   *     http://www.apache.org/licenses/LICENSE-2.0
9   *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16  
17  
18  package validators;
19  
20  
21  import java.io.InputStream;
22  import java.io.IOException;
23  import javax.servlet.jsp.tagext.PageData;
24  import javax.servlet.jsp.tagext.TagLibraryValidator;
25  import javax.servlet.jsp.tagext.ValidationMessage;
26  
27  
28  /**
29   * Example tag library validator that simply dumps the XML version of each
30   * page to standard output (which will typically be sent to the file
31   * <code>$CATALINA_HOME/logs/catalina.out</code>).  To utilize it, simply
32   * include a <code>taglib</code> directive for this tag library at the top
33   * of your JSP page.
34   *
35   * @author Craig McClanahan
36   * @version $Revision: 267129 $ $Date: 2004-03-18 08:40:35 -0800 (Thu, 18 Mar 2004) $
37   */
38  
39  public class DebugValidator extends TagLibraryValidator {
40  
41  
42      // ----------------------------------------------------- Instance Variables
43  
44  
45      // --------------------------------------------------------- Public Methods
46  
47  
48      /**
49       * Validate a JSP page.  This will get invoked once per directive in the
50       * JSP page.  This method will return <code>null</code> if the page is
51       * valid; otherwise the method should return an array of
52       * <code>ValidationMessage</code> objects.  An array of length zero is
53       * also interpreted as no errors.
54       *
55       * @param prefix The value of the prefix argument in this directive
56       * @param uri The value of the URI argument in this directive
57       * @param page The page data for this page
58       */
59      public ValidationMessage[] validate(String prefix, String uri,
60                                          PageData page) {
61  
62          System.out.println("---------- Prefix=" + prefix + " URI=" + uri +
63                             "----------");
64  
65          InputStream is = page.getInputStream();
66          while (true) {
67              try {
68                  int ch = is.read();
69                  if (ch < 0)
70                      break;
71                  System.out.print((char) ch);
72              } catch (IOException e) {
73                  break;
74              }
75          }
76          System.out.println();
77          System.out.println("-----------------------------------------------");
78          return (null);
79  
80      }
81  
82  
83  }