Parser.java

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//                                  //
//  Parser.java                         //
//                                  //
//  experiment.xml.Parser -- fast callback-based XML parser     //
//  Last edited: January 16, 2002 at 11:27 am           //
//                                  //
//  (c) Copyright 2002 Rice University. All rights reserved.    //
//                                  //




package edu.rice.cs.hpc.data.experiment.xml;

import java.io.*;

import org.xml.sax.*;
import org.xml.sax.helpers.*;



//  CLASS PARSER                            //

public class Parser extends Object
{


protected String inputName;

protected InputStream inputStream;

protected LineNumberReader lineNumberReader;

protected Builder builder;

protected Locator locator;




final String parserClass = "com.jclark.xml.sax.Driver";

final String xmlReaderClass = "org.apache.xerces.parsers.SAXParser";





//  INITIALIZATION                                                      //




/*************************************************************************
 *  Creates a Parser.
 ************************************************************************/
    
public Parser(String inputName, InputStream inputStream, Builder builder)
{
    // creation arguments
    this.inputName = inputName;
    this.inputStream = inputStream;
    this.builder = builder;
    this.builder.setParser(this);

    // input line number, for error messages
    this.lineNumberReader = new LineNumberReader(new InputStreamReader(this.inputStream));
}




//  PARSING                             //




/*************************************************************************
 *  Parses the XML file sending parse actions to the builder.
 * @throws Exception 
 ************************************************************************/
    
public void parse()
throws
    Exception
{
    // initialize building
    this.builder.begin();

    // parse the file
    try
    {
        XMLReader parser = new org.apache.xerces.parsers.SAXParser();
        ContentHandler handler = new Handler();
        parser.setContentHandler(handler);
        parser.parse(new InputSource(this.lineNumberReader));
    }
    catch( SAXException e )
    {
        // turn these into parse errors
        this.builder.error(this.getLineNumber());
        return;
    }
    catch( IOException e )
    {
        // let caller handle these, getting the line number from the builder
        this.builder.error(this.getLineNumber());
        throw e;
    }
    catch( Exception e )
    {
        if(e instanceof OldXMLFormatException) {
            //System.err.println("Error found: old XML file");
            throw e;
        } else if(e.getCause() instanceof OldXMLFormatException) {
            //System.err.println("Cause of error: old XML file");
            throw new OldXMLFormatException();
        } else {
            e.printStackTrace();
        }
        // TEMPORARY: do better inside 'builder'
        // turn these into parse errors
        this.builder.error(this.getLineNumber());
        return;
/**************************************************
        // treat everything else as fatal
        int lineNumber = this.getLineNumber();
        String what = this.inputName + ", line " + lineNumber;
        Dialogs.fatalException(Strings.XML_PARSE_EXCEPTION, what, e);
***************************************************/
    }

    // finalize building
    this.builder.end();
}




/*************************************************************************
 *  Returns the 1-based line number of the most recently read input line.
 *
 *  <p>
 *  We'd like this to be the line at which a syntax error was detected,
 *  but the lean parser we're using does not keep track of that. If it
 *  did this method should return <code>this.locator.getLineNumber()</code>.
 *
 ************************************************************************/
    
public int getLineNumber()
{
    return this.lineNumberReader.getLineNumber();
}




//  CLASS HANDLER                                                       //

    public class Handler extends DefaultHandler
    {

    public void setDocumentLocator(Locator locator)
    {
        Parser.this.locator = locator;
    }


    public void startElement(String uri, String localName, String qualifiedName, Attributes attrs)
    {
        // Note: AttributeList.getType() is discarded here

        final int count = attrs.getLength();
        String[] attributeNames  = new String[count];
        String[] attributeValues = new String[count];
        for( int k = 0;  k < count;  k++ )
        {
            attributeNames [k] = attrs.getLocalName (k); // johnmc - was getName, perhaps getLocalName?
            attributeValues[k] = attrs.getValue(k);
        }

        Parser.this.builder.beginElement(localName, attributeNames, attributeValues);
    }


    public void characters(char[] chars, int start, int length)
    {
        String s = new String(chars, start, length).trim();
        if( s.length() > 0 )
        Parser.this.builder.content(s);
    }


    public void endElement(String uri, String localName, String qualifiedName)
    {
        Parser.this.builder.endElement(localName);
    }



}




}