stringreader.java.svn-base

利用J2ME编写的手机应用程序。 功能包括显示图片

package wFramework;

import java.io.IOException;
import java.io.Reader;

/**
 * A subclass that allows "streaming" of internal stringdata
 * Makes it possible to use the KXML parsing engine...
 * 
 * See the 'Reader' class for documentation on the individual methods..
 * @author Marius Bj鴕ge
 *
 */
public class StringReader extends Reader
{
	private String data;
	private int currentpos;
	private int length;
	
	public StringReader(String input)
	{
		data = input;
		currentpos = 0;
		length = data.length();
	}

	public void close() throws IOException 
	{
		data = "";
		currentpos = 0;
		length = 0;
	}
	
	public long skip(long n) throws IOException
	{
		long skipped = n;		
		if (currentpos + n >= length)
		{
			skipped = length - currentpos; 
			currentpos = length - 1;
		}
		else
			currentpos += n;

		return skipped;
	}
	
	public void reset() throws IOException
	{
		currentpos = 0;
	}
	
	public int read(char[] cbuf) throws IOException
	{
		if (currentpos == length)
			return -1;
		
		int numread = 0;

		for (int i = 0; i < cbuf.length; i++)
		{
			int c = read();
			
			if (c >= 0)
				cbuf[i] = (char)c;
			else
				break;
			
			numread++;
		}
		return numread;		
	}
	
	public int read() throws IOException
	{
		if (currentpos == length)
			return -1;

		int c =  data.charAt(currentpos);
		currentpos++;
		return c;
	}

	public int read(char[] cbuf, int offset, int len) throws IOException 
	{
		if (currentpos == length)
			return -1;
		
		int numread = 0;
		for (int i = 0; i < len; i++)
		{
			int c = read();
			if (c >= 0)
			{
				cbuf[i + offset] = (char)c;
				numread++;
			}
			else
				break;
		}
		return numread;
	}
}