/*
 * @(#)Echo03.java 1.5 99/02/09
 *
 * Copyright 2002 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 * 
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 * - Redistribution in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY
 * DAMAGES OR LIABILITIES SUFFERED BY LICENSEE AS A RESULT OF OR
 * RELATING TO USE, MODIFICATION OR DISTRIBUTION OF THIS SOFTWARE OR
 * ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE
 * FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT,
 * SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
 * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF
 * THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS
 * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that this software is not designed, licensed or
 * intended for use in the design, construction, operation or
 * maintenance of any nuclear facility.
 * 
 */

import java.io.*;

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

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

public class Echo03 extends DefaultHandler
{
    StringBuffer textBuffer;
    
    public static void main(String argv[])
    {
        if (argv.length != 1) {
            System.err.println("Usage: cmd filename");
            System.exit(1);
        }
        
        // Use an instance of ourselves as the SAX event handler
        DefaultHandler handler = new Echo03();

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

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

        } catch (Throwable t) {
            t.printStackTrace();
        }
        System.exit(0);
    }

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

    //===========================================================
    // 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 namespaceURI,
                             String sName, // simple name
                             String qName, // qualified name
                             Attributes attrs)
    throws SAXException
    {
        echoText();
        indentLevel++;
        nl(); 
        emit("ELEMENT: ");
        String eName = sName; // element name
        if ("".equals(eName)) eName = qName; // not namespaceAware
        emit("<"+eName);
        if (attrs != null) {
            for (int i = 0; i < attrs.getLength(); i++) {
                String aName = attrs.getLocalName(i); // Attr name 
                if ("".equals(aName)) aName = attrs.getQName(i);
                nl();
                emit("   ATTR: ");
                emit(aName);
                emit("\t\"");
                emit(attrs.getValue(i));
                emit("\"");
            }
        }
        if (attrs.getLength() > 0) nl();
        emit(">");
    }

    public void endElement(String namespaceURI,
                           String sName, // simple name
                           String qName  // qualified name
                          )
    throws SAXException
    {
        echoText();
        nl();
        emit("END_ELM: ");
        String eName = sName; // element name
        if ("".equals(eName)) eName = qName; // not namespaceAware
        emit("</"+eName+">");
        indentLevel--;
    }

    public void characters(char buf[], int offset, int len)
    throws SAXException
    {
        if (textBuffer != null) {
          echoText();
          textBuffer = null;
        }
        String s = new String(buf, offset, len);
        if (textBuffer == null) {
           textBuffer = new StringBuffer(s);
        } else {
           textBuffer.append(s);
        }
    }
    
    //===========================================================
    // Utility Methods ...
    //===========================================================
    
    // Display text accumulated in the character buffer
    private void echoText()
    throws SAXException
    {
        if (textBuffer == null) return;
        nl(); 
        emit("CHARS:   ");
        String s = ""+textBuffer;
        if (!s.trim().equals("")) emit(s);
        textBuffer = null;
    }

    // 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);
        }
    }
}