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: pjm2 $
 * @version $Id: XMLStringParser.java,v 1.7 2001/01/29 15:36:33 pjm2 Exp $
 */
public class XMLStringParser extends DefaultHandler {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.7 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

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

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

//---PUBLIC METHODS---

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

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

    public void startDocument () throws SAXException {
        //System.out.println("XMLPacketParser - Starting parse process...");
    }

    public void endDocument () throws SAXException {
        //System.out.println("XMLPacketParser - I just finished parsing an XML String.");
    }

    /** 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 name, Attributes attrs) throws SAXException {
        indentLevel++;
        tagList.add(name);
        if (attrs != null) {
            for (int i = 0; i < attrs.getLength (); i++) {
                packet.addParam(getPath()+".attributes."+attrs.getLocalName(i), attrs.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 name) throws SAXException {
        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:	1.8
Committed:	Sat Mar 10 00:49:39 2001 UTC (23 years, 1 month ago) by tdb
Branch:	MAIN
Changes since 1.7:	+7 -6 lines
Log Message:	A new parsing library.
#	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	1.8	* @author $Author: pjm2 $
18			* @version $Id: XMLStringParser.java,v 1.7 2001/01/29 15:36:33 pjm2 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	1.8	public final String REVISION = "$Revision: 1.7 $";
28	ajm	1.5
29			//---STATIC METHODS---
30
31			//---CONSTRUCTORS---
32
33			/**
34			* No-args constructor. Generally not used.
35			*/
36			public XMLStringParser () {
37			this.packet = new XMLPacket();
38			}
39
40			/**
41			* Constructor for accepting a reference to an XMLPacket
42			*/
43			public XMLStringParser (XMLPacket packet) {
44			this.packet = packet;
45			}
46
47			//---PUBLIC METHODS---
48
49			/**
50			* Accessor to the XMLPacket.
51			*/
52			public XMLPacket getXMLPacket() {
53			return packet;
54			}
55
56			//===========================================================
57			// SAX DocumentHandler methods
58			//===========================================================
59
60			public void startDocument () throws SAXException {
61			//System.out.println("XMLPacketParser - Starting parse process...");
62			}
63
64			public void endDocument () throws SAXException {
65			//System.out.println("XMLPacketParser - I just finished parsing an XML String.");
66			}
67
68			/** Add each tag's attribute to the XMLPacket.
69			* Note that all attributes within an opening tag are
70			* stored as "someroot.sometag.attributes.attribute_name"
71			* E.g. If <packet> is the root node, then:
72			* <packet machine_name="raptor">
73			* is stored as:
74			* "packet.attributes.machine_name"
75			* within the XMLPacket.
76			*/
77	tdb	1.8	public void startElement (String name, Attributes attrs) throws SAXException {
78	ajm	1.5	indentLevel++;
79			tagList.add(name);
80			if (attrs != null) {
81			for (int i = 0; i < attrs.getLength (); i++) {
82	tdb	1.8	packet.addParam(getPath()+".attributes."+attrs.getLocalName(i), attrs.getValue(i));
83	ajm	1.5	}
84			}
85			}
86
87			/**
88			* When an XML element is finished with, we must remove
89			* the tag name from the tagList and decrement the indent
90			* level.
91			*/
92			public void endElement (String name) throws SAXException {
93			tagList.remove(tagList.size()-1);
94			indentLevel--;
95			}
96
97			/**
98			* Any text falling within a pair of terminal tags must
99			* be added to the XMLPacket. Trim leading and trailing
100			* spaces and do not bother to add if there is no data
101			* specified within the tags.
102			*/
103			public void characters (char[] buf, int offset, int len) throws SAXException {
104			String s = new String(buf, offset, len);
105	pjm2	1.7	packet.addParam(getPath(), s);
106	ajm	1.5	}
107
108			/**
109			* Overrides the {@link java.lang.Object#toString() Object.toString()}
110			* method to provide clean logging (every class should have this).
111			*
112			* This uses the uk.ac.ukc.iscream.util.NameFormat class
113			* to format the toString()
114			*
115			* @return the name of this class and its CVS revision
116			*/
117			public String toString() {
118			return FormatName.getName(
119			_name,
120			getClass().getName(),
121			REVISION);
122			}
123
124			//---PRIVATE METHODS---
125
126			//===========================================================
127			// Helpers ...
128			//===========================================================
129
130			/**
131			* Return the heirarchical string to be used as a key value
132			* in the XMLPacket.
133			*/
134			private String getPath () {
135			String path = (String)tagList.get(0);
136			if (tagList.size() > 0) {
137			for (int i = 1 ; i < tagList.size() ; i++) {
138			path = path + "." + (String)tagList.get(i);
139			}
140			}
141			return path;
142			}
143
144			//---ACCESSOR/MUTATOR METHODS---
145
146			//---ATTRIBUTES---
147
148	tdb	1.6	/**
149			* To keep track of our identation level
150			*/
151	ajm	1.5	private int indentLevel = 0;
152	tdb	1.6
153			/**
154			* An ArrayList of tags
155			*/
156	ajm	1.5	private ArrayList tagList = new ArrayList();
157	tdb	1.6
158			/**
159			* A reference to the XMLPacket we are making
160			*/
161	ajm	1.5	private XMLPacket packet;
162
163			/**
164			* This is the friendly identifier of the
165			* component this class is running in.
166			* eg, a Filter may be called "filter1",
167			* If this class does not have an owning
168			* component, a name from the configuration
169			* can be placed here. This name could also
170			* be changed to null for utility classes.
171			*/
172			private String _name = null;
173
174			//---STATIC ATTRIBUTES---
175
176			}