cms/util/XMLStringParser.java

//---PACKAGE DECLARATION---
package uk.ac.ukc.iscream.util;

//---IMPORTS---
import java.io.*;
import java.util.ArrayList;

import org.xml.sax.*;
import org.xml.sax.helpers.*;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;

/**
 * XMLStringParser - Used to assist in creating XMLPacket objects.
 *
 * @author  $Author: tdb1 $
 * @version $Id: XMLStringParser.java,v 1.8 2001/03/10 00:49:39 tdb1 Exp $
 */
public class XMLStringParser extends DefaultHandler {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.8 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * No-args constructor.  Generally not used.
     */
    public XMLStringParser () {
        _packet = new XMLPacket();
    }

    /**
     * Constructor for accepting a reference to an XMLPacket
     */
    public XMLStringParser (XMLPacket packet) {
        _packet = packet;
    }

//---PUBLIC METHODS---

    /**
     * Accessor to the XMLPacket.
     */ 
    public XMLPacket getXMLPacket() {
        return _packet;
    }

    //===========================================================
    // SAX DocumentHandler methods
    //===========================================================

    /** 
     * Add each tag's attribute to the XMLPacket.
     * Note that all attributes within an opening tag are
     * stored as "someroot.sometag.attributes.attribute_name"
     * E.g. If <packet> is the root node, then:
     *     <packet machine_name="raptor">
     * is stored as:
     *     "packet.attributes.machine_name"
     * within the XMLPacket.
     */
    public void startElement (String uri, String name, String qName, Attributes atts) {
            _indentLevel++;
        _tagList.add(name);
        if (atts != null) {
            for (int i = 0; i < atts.getLength (); i++) {
                _packet.addParam(getPath()+".attributes."+atts.getLocalName(i), atts.getValue(i));
            }
        }
    }

    /**
     * When an XML element is finished with, we must remove
     * the tag name from the tagList and decrement the indent
     * level.
     */
    public void endElement (String uri, String name, String qName) {
            _tagList.remove(_tagList.size() - 1);    
        _indentLevel--;
    }


    /**
     * Any text falling within a pair of terminal tags must
     * be added to the XMLPacket.  Trim leading and trailing
     * spaces and do not bother to add if there is no data
     * specified within the tags.
     */
    public void characters (char[] buf, int offset, int len) throws SAXException {
        String s = new String(buf, offset, len);
        _packet.addParam(getPath(), s);
    }

    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.ac.ukc.iscream.util.NameFormat class
     * to format the toString()
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return FormatName.getName(
            _name,
            getClass().getName(),
            REVISION);
    }

//---PRIVATE METHODS---

    //===========================================================
    // Helpers ...
    //===========================================================
    
    /**
     * Return the heirarchical string to be used as a key value
     * in the XMLPacket.
     */
    private String getPath () {
        String path = (String) _tagList.get(0);
        if (_tagList.size() > 0) {
            for (int i = 1 ; i < _tagList.size() ; i++) {
                path = path + "." + (String) _tagList.get(i);
            }
        }
        return path;
    }

//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---

    /**
     * To keep track of our identation level
     */
    private int _indentLevel = 0;
    
    /**
     * An ArrayList of tags
     */
    private ArrayList _tagList = new ArrayList();
    
    /**
     * A reference to the XMLPacket we are making
     */
    private XMLPacket _packet;
    
    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    private String _name = null;

//---STATIC ATTRIBUTES---

}
Revision:	1.9
Committed:	Sat Mar 10 02:03:55 2001 UTC (23 years, 1 month ago) by tdb
Branch:	MAIN
Changes since 1.8:	+26 -32 lines
Log Message:	Changed to use the newer parsing libraries.
#	User	Rev	Content
1	ajm	1.5	//---PACKAGE DECLARATION---
2			package uk.ac.ukc.iscream.util;
3
4			//---IMPORTS---
5			import java.io.*;
6			import java.util.ArrayList;
7
8			import org.xml.sax.*;
9	tdb	1.8	import org.xml.sax.helpers.*;
10	ajm	1.5	import javax.xml.parsers.SAXParserFactory;
11			import javax.xml.parsers.ParserConfigurationException;
12			import javax.xml.parsers.SAXParser;
13
14			/**
15			* XMLStringParser - Used to assist in creating XMLPacket objects.
16			*
17	tdb	1.9	* @author $Author: tdb1 $
18			* @version $Id: XMLStringParser.java,v 1.8 2001/03/10 00:49:39 tdb1 Exp $
19	ajm	1.5	*/
20	tdb	1.8	public class XMLStringParser extends DefaultHandler {
21	ajm	1.5
22			//---FINAL ATTRIBUTES---
23
24			/**
25			* The current CVS revision of this class
26			*/
27	tdb	1.9	public final String REVISION = "$Revision: 1.8 $";
28	ajm	1.5
29			//---STATIC METHODS---
30
31			//---CONSTRUCTORS---
32
33			/**
34			* No-args constructor. Generally not used.
35			*/
36			public XMLStringParser () {
37	tdb	1.9	_packet = new XMLPacket();
38	ajm	1.5	}
39
40			/**
41			* Constructor for accepting a reference to an XMLPacket
42			*/
43			public XMLStringParser (XMLPacket packet) {
44	tdb	1.9	_packet = packet;
45	ajm	1.5	}
46
47			//---PUBLIC METHODS---
48
49			/**
50			* Accessor to the XMLPacket.
51			*/
52			public XMLPacket getXMLPacket() {
53	tdb	1.9	return _packet;
54	ajm	1.5	}
55
56			//===========================================================
57			// SAX DocumentHandler methods
58			//===========================================================
59
60	tdb	1.9	/**
61			* Add each tag's attribute to the XMLPacket.
62	ajm	1.5	* Note that all attributes within an opening tag are
63			* stored as "someroot.sometag.attributes.attribute_name"
64			* E.g. If <packet> is the root node, then:
65			* <packet machine_name="raptor">
66			* is stored as:
67			* "packet.attributes.machine_name"
68			* within the XMLPacket.
69			*/
70	tdb	1.9	public void startElement (String uri, String name, String qName, Attributes atts) {
71			_indentLevel++;
72			_tagList.add(name);
73			if (atts != null) {
74			for (int i = 0; i < atts.getLength (); i++) {
75			_packet.addParam(getPath()+".attributes."+atts.getLocalName(i), atts.getValue(i));
76	ajm	1.5	}
77			}
78			}
79
80			/**
81			* When an XML element is finished with, we must remove
82			* the tag name from the tagList and decrement the indent
83			* level.
84			*/
85	tdb	1.9	public void endElement (String uri, String name, String qName) {
86			_tagList.remove(_tagList.size() - 1);
87			_indentLevel--;
88	ajm	1.5	}
89
90	tdb	1.9
91	ajm	1.5	/**
92			* Any text falling within a pair of terminal tags must
93			* be added to the XMLPacket. Trim leading and trailing
94			* spaces and do not bother to add if there is no data
95			* specified within the tags.
96			*/
97			public void characters (char[] buf, int offset, int len) throws SAXException {
98			String s = new String(buf, offset, len);
99	tdb	1.9	_packet.addParam(getPath(), s);
100	ajm	1.5	}
101
102			/**
103			* Overrides the {@link java.lang.Object#toString() Object.toString()}
104			* method to provide clean logging (every class should have this).
105			*
106			* This uses the uk.ac.ukc.iscream.util.NameFormat class
107			* to format the toString()
108			*
109			* @return the name of this class and its CVS revision
110			*/
111			public String toString() {
112			return FormatName.getName(
113			_name,
114			getClass().getName(),
115			REVISION);
116			}
117
118			//---PRIVATE METHODS---
119
120			//===========================================================
121			// Helpers ...
122			//===========================================================
123
124			/**
125			* Return the heirarchical string to be used as a key value
126			* in the XMLPacket.
127			*/
128			private String getPath () {
129	tdb	1.9	String path = (String) _tagList.get(0);
130			if (_tagList.size() > 0) {
131			for (int i = 1 ; i < _tagList.size() ; i++) {
132			path = path + "." + (String) _tagList.get(i);
133	ajm	1.5	}
134			}
135			return path;
136			}
137
138			//---ACCESSOR/MUTATOR METHODS---
139
140			//---ATTRIBUTES---
141
142	tdb	1.6	/**
143			* To keep track of our identation level
144			*/
145	tdb	1.9	private int _indentLevel = 0;
146	tdb	1.6
147			/**
148			* An ArrayList of tags
149			*/
150	tdb	1.9	private ArrayList _tagList = new ArrayList();
151	tdb	1.6
152			/**
153			* A reference to the XMLPacket we are making
154			*/
155	tdb	1.9	private XMLPacket _packet;
156	ajm	1.5
157			/**
158			* This is the friendly identifier of the
159			* component this class is running in.
160			* eg, a Filter may be called "filter1",
161			* If this class does not have an owning
162			* component, a name from the configuration
163			* can be placed here. This name could also
164			* be changed to null for utility classes.
165			*/
166			private String _name = null;
167
168			//---STATIC ATTRIBUTES---
169
170			}