Source code: org/htmlparser/scanners/FrameScanner.java
1 // $Header: /home/cvs/jakarta-jmeter/src/htmlparser/org/htmlparser/scanners/FrameScanner.java,v 1.2 2004/02/10 13:41:09 woolfel Exp $
2 /*
3 * ====================================================================
4 * Copyright 2002-2004 The Apache Software Foundation.
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 *
18 */
19
20 // The developers of JMeter and Apache are greatful to the developers
21 // of HTMLParser for giving Apache Software Foundation a non-exclusive
22 // license. The performance benefits of HTMLParser are clear and the
23 // users of JMeter will benefit from the hard work the HTMLParser
24 // team. For detailed information about HTMLParser, the project is
25 // hosted on sourceforge at http://htmlparser.sourceforge.net/.
26 //
27 // HTMLParser was originally created by Somik Raha in 2000. Since then
28 // a healthy community of users has formed and helped refine the
29 // design so that it is able to tackle the difficult task of parsing
30 // dirty HTML. Derrick Oswald is the current lead developer and was kind
31 // enough to assist JMeter.
32
33 package org.htmlparser.scanners;
34
35
36 //////////////////
37 // Java Imports //
38 //////////////////
39 import java.util.Hashtable;
40
41 import org.htmlparser.tags.FrameTag;
42 import org.htmlparser.tags.Tag;
43 import org.htmlparser.tags.data.TagData;
44 import org.htmlparser.util.LinkProcessor;
45 import org.htmlparser.util.ParserException;
46
47 /**
48 * Scans for the Frame Tag. This is a subclass of TagScanner, and is called using a
49 * variant of the template method. If the evaluate() method returns true, that means the
50 * given string contains an image tag. Extraction is done by the scan method thereafter
51 * by the user of this class.
52 */
53 public class FrameScanner extends TagScanner
54 {
55 /**
56 * Overriding the default constructor
57 */
58 public FrameScanner()
59 {
60 super();
61 }
62 /**
63 * Overriding the constructor to accept the filter
64 */
65 public FrameScanner(String filter)
66 {
67 super(filter);
68 }
69 /**
70 * Extract the location of the image, given the string to be parsed, and the url
71 * of the html page in which this tag exists.
72 * @param s String to be parsed
73 * @param url URL of web page being parsed
74 */
75 public String extractFrameLocn(Tag tag, String url) throws ParserException
76 {
77 try
78 {
79 Hashtable table = tag.getAttributes();
80 String relativeFrame = (String) table.get("SRC");
81 if (relativeFrame == null)
82 return "";
83 else
84 return (new LinkProcessor()).extract(relativeFrame, url);
85 }
86 catch (Exception e)
87 {
88 String msg;
89 if (tag != null)
90 msg = tag.getText();
91 else
92 msg = "null";
93 throw new ParserException(
94 "HTMLFrameScanner.extractFrameLocn() : Error in extracting frame location from tag "
95 + msg,
96 e);
97 }
98 }
99
100 public String extractFrameName(Tag tag, String url)
101 {
102 return tag.getAttribute("NAME");
103 }
104
105 /**
106 * @see org.htmlparser.scanners.TagScanner#getID()
107 */
108 public String[] getID()
109 {
110 String[] ids = new String[1];
111 ids[0] = "FRAME";
112 return ids;
113 }
114
115 protected Tag createTag(TagData tagData, Tag tag, String url)
116 throws ParserException
117 {
118 String frameUrl = extractFrameLocn(tag, url);
119 String frameName = extractFrameName(tag, url);
120
121 return new FrameTag(tagData, frameUrl, frameName);
122 }
123
124 }