xmlreader.java

是一个JABBER的J2ME的实现

/*
 * Copyright 2004 Grzegorz Grasza [e-mail]
 *
 * This file is part of mobber. Mobber is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by the Free 
 * Software Foundation; either version 2 of the License, or (at your option) any later version.
 * Mobber is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with mobber;
 * if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307 USA .
 */

package utils;

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

public class XmlReader extends InputStreamReader
{
	public final static int START_DOCUMENT = 0;
	public final static int END_DOCUMENT = 1;
	public final static int START_TAG = 2;
	public final static int END_TAG = 3;
	public final static int TEXT = 4;
	
	private Stack tags;
	private boolean inside_tag;
	private String tagName;
	private String text;
	private Hashtable attributes = new Hashtable();
	private int c;
	private int type = START_DOCUMENT;
	
	public XmlReader(InputStream in) throws IOException, UnsupportedEncodingException
	{
		super(in, "UTF-8");
		tags = new Stack();
		inside_tag = false;
	}
	
	public int next() throws IOException
	{
		c = read();
		if(c <= ' ') // omit white space
			while((c = read()) <= ' ' && c!=-1);
		if(c==-1)
		{
			type = END_DOCUMENT;
			return type;
		}	
		
		if(c == '<' || (c == '/' && !inside_tag))
		{
			inside_tag = true;
			// reset all
			tagName = null;
			text = null;
			attributes.clear();
			
			if(c == '<')
				c = read();
			if(c == '/')
			{
				type = END_TAG;
				c = read();
				tagName = readName('>');
			}
			else if(c == '?' || c == '!') // ignore xml heading & comments
			{
				while((c = read()) != '>');
				next();
			}
			else
			{
				type = START_TAG;
				tagName = readName(' ');
				
				String attribute = "";
				String value = "";
				while(c == ' ')
				{
					c = read();
					attribute = readName('=');
					
					c = read(); // '''
					c = read();
					value = readText('\'');
					c = read();
					attributes.put(attribute, value);
				}
				if(c != '/')
					inside_tag = false;
			}
		}
		else if(c == '>' && inside_tag) // last tag ended
		{
			type = END_TAG;
			inside_tag = false;
		}
		else
		{
			tagName = null;
			attributes.clear();
			
			type = TEXT;
			text = readText('<');
		}
		
		return type;
	}
	
	public int getType()
	{
		return type;
	}
	
	public String getName()
	{
		return tagName;
	}
	
	public String getAttribute(String name)
	{
		return (String)attributes.get(name);
	}
	
	public Enumeration getAttributes()
	{
		return attributes.keys();
	}
	
	public String getText()
	{
		return text;
	}
	
	private String readText(int end) throws IOException
	{
		StringBuffer output = new StringBuffer("");
		while(c != end)
		{
			if(c == '&')
			{
				c = read();
				switch(c)
				{
					case 'l': output.append('<');
						break;
					case 'g': output.append('>');
						break;
					case 'a':
						if(read()=='m')
							output.append('&');
						else
							output.append('\'');
						break;
					case 'q': output.append('"');
						break;
					case 'n': output.append(' ');
						break;
					default: output.append('?');
				}
				
				while((c = read()) != ';');
			}
			else if(c == '\\')
			{
				if((c = read()) == '<')
					break;
				else
					output.append((char) c);
			}
			else
				output.append((char) c);
			c = read();
		}
		//while((c = read()) != end);
		return output.toString();
	}
	private String readName(int end) throws IOException
	{
		StringBuffer output = new StringBuffer("");
		do output.append((char) c);
		while((c = read()) != end && c != '>' && c != '/');
		return output.toString();
	}
};