server/XMLReader/XMLPacketMaker.java

import java.io.*;
import java.util.ArrayList;

import org.xml.sax.*;

import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;

// Paul Mutton, pjm2@ukc.ac.uk

// XMLPacketMaker - Creates an XMLPacket object.
public class XMLPacketMaker extends HandlerBase {

    public XMLPacketMaker () {
        // default no-args constructor.
    }

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

    public static void main(String[] args){
        if (args.length != 1) {
            System.err.println ("Usage: cmd filename");
            System.exit (1);
        }

        // Use the default (non-validating) parser
        SAXParserFactory factory = SAXParserFactory.newInstance();
        try {
            // Set up output stream
            out = new OutputStreamWriter (System.out, "UTF8");

            // Create the XMLPacket to store values in.
            packet = new XMLPacket();

            // Parse the input
            SAXParser saxParser = factory.newSAXParser();
            saxParser.parse(new File(args[0]), new XMLPacketMaker(packet));

            // Print out the entire contents of the packet's HashMap.
            System.out.println("XMLPacket contents: -");
            packet.printAll();

        } catch (Throwable t) {
            System.out.println("The recieved packet did not contain valid XML, so I'm gonna reject it.");
            //t.printStackTrace ();
        }
        System.exit (0);
    }

    static private Writer out;
    private String indentString = "    "; // Amount to indent
    private int indentLevel = 0;

    // For storing the tag heirarchy.
    private ArrayList tagList = new ArrayList();
    static private XMLPacket packet = null;

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

    public void startDocument () throws SAXException {
        // No purpose currently.
    }

    public void endDocument () throws SAXException {
        // No purpose currently.
    }

    // 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, AttributeList attrs) throws SAXException {
        indentLevel++;
        tagList.add(name);
        if (attrs != null) {
            for (int i = 0; i < attrs.getLength (); i++) {
                packet.addParam(getPath()+".attributes."+attrs.getName(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);
        if (!s.trim().equals("")) {
            packet.addParam(getPath(), s);
        }
    }


    //===========================================================
    // 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;
    }
    
}
Revision:	1.9
Committed:	Tue Nov 14 12:36:11 2000 UTC (23 years, 5 months ago) by pjm2
Branch:	MAIN
Changes since 1.8:	+2 -1 lines
Log Message:	Added test.bad - this is a file containing malformed XML markup to see if the error handling in XMLPacketManager works properly. XMLPacketMaker has been altered accordingly, catching Throwable exceptions.
#	User	Rev	Content
1	pjm2	1.3	import java.io.*;
2			import java.util.ArrayList;
3
4			import org.xml.sax.*;
5
6	pjm2	1.7	import javax.xml.parsers.SAXParserFactory;
7			import javax.xml.parsers.ParserConfigurationException;
8			import javax.xml.parsers.SAXParser;
9	pjm2	1.3
10	pjm2	1.7	// Paul Mutton, pjm2@ukc.ac.uk
11	pjm2	1.3
12	pjm2	1.7	// XMLPacketMaker - Creates an XMLPacket object.
13	pjm2	1.3	public class XMLPacketMaker extends HandlerBase {
14	pjm2	1.5
15			public XMLPacketMaker () {
16			// default no-args constructor.
17			}
18
19			// Constructor for accepting a reference to an XMLPacket
20			public XMLPacketMaker (XMLPacket packet) {
21			this.packet = packet;
22			}
23
24	pjm2	1.3	public static void main(String[] args){
25			if (args.length != 1) {
26			System.err.println ("Usage: cmd filename");
27			System.exit (1);
28			}
29
30			// Use the default (non-validating) parser
31			SAXParserFactory factory = SAXParserFactory.newInstance();
32			try {
33			// Set up output stream
34			out = new OutputStreamWriter (System.out, "UTF8");
35
36	pjm2	1.5	// Create the XMLPacket to store values in.
37			packet = new XMLPacket();
38
39	pjm2	1.3	// Parse the input
40			SAXParser saxParser = factory.newSAXParser();
41	pjm2	1.5	saxParser.parse(new File(args[0]), new XMLPacketMaker(packet));
42
43	pjm2	1.8	// Print out the entire contents of the packet's HashMap.
44			System.out.println("XMLPacket contents: -");
45	pjm2	1.7	packet.printAll();
46	pjm2	1.3
47			} catch (Throwable t) {
48	pjm2	1.9	System.out.println("The recieved packet did not contain valid XML, so I'm gonna reject it.");
49			//t.printStackTrace ();
50	pjm2	1.3	}
51			System.exit (0);
52			}
53
54			static private Writer out;
55			private String indentString = " "; // Amount to indent
56			private int indentLevel = 0;
57
58	pjm2	1.4	// For storing the tag heirarchy.
59	pjm2	1.3	private ArrayList tagList = new ArrayList();
60	pjm2	1.5	static private XMLPacket packet = null;
61	pjm2	1.3
62			//===========================================================
63			// SAX DocumentHandler methods
64			//===========================================================
65
66			public void startDocument () throws SAXException {
67	pjm2	1.8	// No purpose currently.
68	pjm2	1.3	}
69
70			public void endDocument () throws SAXException {
71	pjm2	1.8	// No purpose currently.
72	pjm2	1.3	}
73
74	pjm2	1.8	// Add each tag's attribute to the XMLPacket.
75			// Note that all attributes within an opening tag are
76			// stored as "someroot.sometag.attributes.attribute_name"
77			// E.g. If <packet> is the root node, then:
78			// <packet machine_name="raptor">
79			// is stored as:
80			// "packet.attributes.machine_name"
81			// within the XMLPacket.
82	pjm2	1.3	public void startElement (String name, AttributeList attrs) throws SAXException {
83			indentLevel++;
84	pjm2	1.5	tagList.add(name);
85	pjm2	1.3	if (attrs != null) {
86			for (int i = 0; i < attrs.getLength (); i++) {
87	pjm2	1.8	packet.addParam(getPath()+".attributes."+attrs.getName(i), attrs.getValue(i));
88	pjm2	1.3	}
89			}
90			}
91
92	pjm2	1.8	// When an XML element is finished with, we must remove
93			// the tag name from the tagList and decrement the indent
94			// level.
95	pjm2	1.3	public void endElement (String name) throws SAXException {
96	pjm2	1.5	tagList.remove(tagList.size()-1);
97	pjm2	1.3	indentLevel--;
98			}
99
100	pjm2	1.8	// Any text falling within a pair of terminal tags must
101			// be added to the XMLPacket. Trim leading and trailing
102			// spaces and do not bother to add if there is no data
103			// specified within the tags.
104	pjm2	1.3	public void characters (char[] buf, int offset, int len) throws SAXException {
105			String s = new String(buf, offset, len);
106	pjm2	1.5	if (!s.trim().equals("")) {
107	pjm2	1.6	packet.addParam(getPath(), s);
108	pjm2	1.5	}
109	pjm2	1.3	}
110
111	pjm2	1.8
112	pjm2	1.3	//===========================================================
113			// Helpers ...
114			//===========================================================
115	pjm2	1.8
116	pjm2	1.6
117	pjm2	1.7	// Return the heirarchical string to be used as a key value
118			// in the XMLPacket.
119	pjm2	1.6	private String getPath () {
120			String path = (String)tagList.get(0);
121			if (tagList.size() > 0) {
122			for (int i = 1 ; i < tagList.size() ; i++) {
123			path = path + "." + (String)tagList.get(i);
124			}
125			}
126			return path;
127	pjm2	1.3	}
128	pjm2	1.8
129	pjm2	1.3	}