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));

            // By means of example, print out some things from the packet: -
            System.out.println("bung.wibble="+packet.getParam("bung.wibble"));
            System.out.println("bung.ping.value1="+packet.getParam("bung.ping.value1"));            

            // Print out the entire contents of the packet.
            packet.printAll();

        } catch (Throwable t) {
            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 {
        nl();
        nl();
        emit ("START DOCUMENT");
        nl();
        emit ("<?xml version='1.0' encoding='UTF-8'?>");
    }

    public void endDocument () throws SAXException {
        nl(); emit ("END DOCUMENT");
        try {
            nl();
            out.flush ();
        } catch (IOException e) {
            throw new SAXException ("I/O error", e);
        }
    }

    public void startElement (String name, AttributeList attrs) throws SAXException {
        indentLevel++;
        tagList.add(name);
        nl(); emit ("ELEMENT: ");
        emit ("<"+name);
        if (attrs != null) {
            for (int i = 0; i < attrs.getLength (); i++) {
                nl();
                emit("   ATTR: ");
                emit (attrs.getName (i));
                emit ("\t\"");
                emit (attrs.getValue (i));
                emit ("\"");
            }
        }
        if (attrs.getLength() > 0) nl();
        emit (">");
    }

    public void endElement (String name) throws SAXException {
        nl();
        emit ("END_ELM: ");
        emit ("</"+name+">");
        tagList.remove(tagList.size()-1);    
        indentLevel--;
    }

    public void characters (char[] buf, int offset, int len) throws SAXException {
        nl(); emit ("CHARS:   ");
        String s = new String(buf, offset, len);
        if (!s.trim().equals("")) {
            emit (s);
            packet.addParam(getPath(), s);
        }
    }

    //===========================================================
    // Helpers ...
    //===========================================================

    // Wrap I/O exceptions in SAX exceptions, to
    // suit handler signature requirements
    private void emit (String s) throws SAXException {
        try {
            out.write (s);
            out.flush ();
        } catch (IOException e) {
            throw new SAXException ("I/O error", e);
        }
    }

    // Start a new line
    // and indent the next line appropriately
    private void nl () throws SAXException {
        String lineEnd =  System.getProperty("line.separator");
        try {
            out.write (lineEnd);
            for (int i=0; i < indentLevel; i++) out.write(indentString);
        } catch (IOException e) {
            throw new SAXException ("I/O error", e);
        }
    }
    
    // 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:	1.7
Committed:	Tue Nov 14 12:01:19 2000 UTC (24 years ago) by pjm2
Branch:	MAIN
Changes since 1.6:	+12 -6 lines
Log Message:	Added a function to XMLPacket.java that allows the entire contents of the packet to be echoed to the screen. The main method of XMLPacketMaker now makes use of this feature.
#	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	1.7	// By means of example, print out some things from the packet: -
44	pjm2	1.6	System.out.println("bung.wibble="+packet.getParam("bung.wibble"));
45	pjm2	1.7	System.out.println("bung.ping.value1="+packet.getParam("bung.ping.value1"));
46
47			// Print out the entire contents of the packet.
48			packet.printAll();
49	pjm2	1.3
50			} catch (Throwable t) {
51			t.printStackTrace ();
52			}
53			System.exit (0);
54			}
55
56			static private Writer out;
57			private String indentString = " "; // Amount to indent
58			private int indentLevel = 0;
59
60	pjm2	1.4	// For storing the tag heirarchy.
61	pjm2	1.3	private ArrayList tagList = new ArrayList();
62	pjm2	1.5	static private XMLPacket packet = null;
63	pjm2	1.3
64			//===========================================================
65			// SAX DocumentHandler methods
66			//===========================================================
67
68			public void startDocument () throws SAXException {
69			nl();
70			nl();
71			emit ("START DOCUMENT");
72			nl();
73			emit ("<?xml version='1.0' encoding='UTF-8'?>");
74			}
75
76			public void endDocument () throws SAXException {
77			nl(); emit ("END DOCUMENT");
78			try {
79			nl();
80			out.flush ();
81			} catch (IOException e) {
82			throw new SAXException ("I/O error", e);
83			}
84			}
85
86			public void startElement (String name, AttributeList attrs) throws SAXException {
87			indentLevel++;
88	pjm2	1.5	tagList.add(name);
89	pjm2	1.3	nl(); emit ("ELEMENT: ");
90			emit ("<"+name);
91			if (attrs != null) {
92			for (int i = 0; i < attrs.getLength (); i++) {
93			nl();
94			emit(" ATTR: ");
95			emit (attrs.getName (i));
96			emit ("\t\"");
97			emit (attrs.getValue (i));
98			emit ("\"");
99			}
100			}
101			if (attrs.getLength() > 0) nl();
102			emit (">");
103			}
104
105			public void endElement (String name) throws SAXException {
106			nl();
107			emit ("END_ELM: ");
108			emit ("</"+name+">");
109	pjm2	1.5	tagList.remove(tagList.size()-1);
110	pjm2	1.3	indentLevel--;
111			}
112
113			public void characters (char[] buf, int offset, int len) throws SAXException {
114			nl(); emit ("CHARS: ");
115			String s = new String(buf, offset, len);
116	pjm2	1.5	if (!s.trim().equals("")) {
117			emit (s);
118	pjm2	1.6	packet.addParam(getPath(), s);
119	pjm2	1.5	}
120	pjm2	1.3	}
121
122			//===========================================================
123			// Helpers ...
124			//===========================================================
125
126			// Wrap I/O exceptions in SAX exceptions, to
127			// suit handler signature requirements
128			private void emit (String s) throws SAXException {
129			try {
130			out.write (s);
131			out.flush ();
132			} catch (IOException e) {
133			throw new SAXException ("I/O error", e);
134			}
135			}
136
137			// Start a new line
138			// and indent the next line appropriately
139			private void nl () throws SAXException {
140			String lineEnd = System.getProperty("line.separator");
141			try {
142			out.write (lineEnd);
143			for (int i=0; i < indentLevel; i++) out.write(indentString);
144			} catch (IOException e) {
145			throw new SAXException ("I/O error", e);
146			}
147	pjm2	1.6	}
148
149	pjm2	1.7	// Return the heirarchical string to be used as a key value
150			// in the XMLPacket.
151	pjm2	1.6	private String getPath () {
152			String path = (String)tagList.get(0);
153			if (tagList.size() > 0) {
154			for (int i = 1 ; i < tagList.size() ; i++) {
155			path = path + "." + (String)tagList.get(i);
156			}
157			}
158			return path;
159	pjm2	1.3	}
160			}