|
1
|
<!--
|
|
2
|
* saxparser.html
|
|
3
|
*
|
|
4
|
* Authors: Jivka Bojilova
|
|
5
|
* Copyright: 2000 Regents of the University of California and the
|
|
6
|
* National Center for Ecological Analysis and Synthesis
|
|
7
|
* For Details: http://www.nceas.ucsb.edu/
|
|
8
|
* Created: 2000 April 5
|
|
9
|
* Version: 0.01
|
|
10
|
* File Info: '$Id: saxparser.html 2310 2004-09-21 09:01:22Z jones $'
|
|
11
|
*
|
|
12
|
* October Meeting SDSC, 2000
|
|
13
|
-->
|
|
14
|
<HTML>
|
|
15
|
<HEAD>
|
|
16
|
<TITLE>Metacat</TITLE>
|
|
17
|
<link rel="stylesheet" type="text/css" href="@docrooturl@default.css">
|
|
18
|
</HEAD>
|
|
19
|
<BODY>
|
|
20
|
<table width="100%">
|
|
21
|
<tr>
|
|
22
|
<td class="tablehead" colspan="2"><p class="label">XML Parsing with SAX</p></td>
|
|
23
|
<td class="tablehead" colspan="2" align="right">
|
|
24
|
<a href="./metacatgetlog.html">Back</a> | <a href="./metacattour.html">Home</a> |
|
|
25
|
<a href="./xmlindex.html">Next</a>
|
|
26
|
</td>
|
|
27
|
</tr>
|
|
28
|
</table>
|
|
29
|
<P>SAX, the <i>Simple API for XML</i>, is
|
|
30
|
a standard interface for event-based XML parsing. The SAX API provides implemented
|
|
31
|
interfaces for many different XML parsers. Metacat requires a SAX2
|
|
32
|
API/Java1.2 with any SAX2-compatible XML parser.
|
|
33
|
<P>To avoid tying Metacat to any specific SAX parser, XMLReaderFactory is used
|
|
34
|
as the SAX interface to Metacat for easy plugability of parsers. The SAX parser
|
|
35
|
used must be set in the <a href="./properties.html">Metacat Properties</a> file.</p>
|
|
36
|
<p>The following is an example of instatiating a parser for Metacat.</p>
|
|
37
|
<PRE>
|
|
38
|
XMLReader parser = null;
|
|
39
|
// Set up the SAX document handlers for parsing
|
|
40
|
try {
|
|
41
|
ContentHandler chandler = new DBSAXHandler(conn, action, docid, user);
|
|
42
|
EntityResolver dbresolver = new DBEntityResolver(conn, (DBSAXHandler)chandler);
|
|
43
|
DTDHandler dtdhandler = new DBDTDHandler(conn);
|
|
44
|
|
|
45
|
// Get an instance of the parser
|
|
46
|
MetacatUtil util = new MetacatUtil();
|
|
47
|
// Get the class name of SAX driver from some XML parser like:
|
|
48
|
// org.apache.xerces.parsers.SAXParser
|
|
49
|
<span class="emphasis">String parserName = util.getOption("saxparser");</span>
|
|
50
|
// Given a class name, this method attempts to load and instantiate the class as an XML reader
|
|
51
|
<span class="emphasis">parser = XMLReaderFactory.createXMLReader(parserName);</span>
|
|
52
|
|
|
53
|
// Turn off validation
|
|
54
|
parser.setFeature("http://xml.org/sax/features/validation", false);
|
|
55
|
|
|
56
|
parser.setProperty("http://xml.org/sax/properties/declaration-handler", chandler);
|
|
57
|
parser.setProperty("http://xml.org/sax/properties/lexical-handler", chandler);
|
|
58
|
|
|
59
|
// Set Handlers in the parser to receive XML parsing events
|
|
60
|
parser.setContentHandler((ContentHandler)chandler);
|
|
61
|
parser.setEntityResolver((EntityResolver)dbresolver);
|
|
62
|
parser.setDTDHandler((DTDHandler)dtdhandler);
|
|
63
|
parser.setErrorHandler((ErrorHandler)chandler);
|
|
64
|
|
|
65
|
} catch (SAXException saxe) {
|
|
66
|
throw saxe;
|
|
67
|
}
|
|
68
|
|
|
69
|
</PRE>
|
|
70
|
|
|
71
|
<br>
|
|
72
|
<a href="./metacatgetlog.html">Back</a> | <a href="./metacattour.html">Home</a> |
|
|
73
|
<a href="./xmlindex.html">Next</a>
|
|
74
|
|
|
75
|
</BODY>
|
|
76
|
</HTML>
|
|
77
|
|
