pushbacktest.java

java应用开发详解

import java.io.PushbackInputStream;
import java.io.IOException;
import java.util.Vector;

class PushbackTest
{
	    
	public static void main(String[] args) 
	{
        	Vector vec = new Vector();
        	PushbackInputStream pushin = new PushbackInputStream(System.in);
        	boolean eof;
        	while (true) 
        	{	
            		if (eof = readNumber(pushin, vec))
                	break;
            		if (eof = readString(pushin, vec))
               		break;
            		System.out.println(vec);
        	}
        	System.out.println(vec);
    	}
    	
    	private static boolean readNumber(PushbackInputStream in, Vector vec) 
    	{
        	StringBuffer sb = new StringBuffer();
        	int c = -1;
        	// read number
        	try 
        	{
            		for (c = in.read(); c >= 0; c = in.read()) 
            		{
                		if (Character.isDigit((char)c)) 
                		{
                    			sb.append((char)c);
                		} 
                		else 
                		{
                    			in.unread(c);
                    			break;
                		}
            		}
        	} 
        	catch (IOException e) 
        	{
        	}
        
        	if (sb.length() > 0)
            	vec.addElement(Integer.valueOf(sb.toString()));
        	return (c == -1);
    	}
    	
    	private static boolean readString(PushbackInputStream in, Vector vec) 
    	{
        	StringBuffer sb = new StringBuffer();
        	int c = -1;
        	try 
        	{
            		for (c = in.read(); c >= 0; c = in.read()) 
            		{
                		if (Character.isDigit((char)c)) 
                		{
                    			in.unread(c);
                    			break;
                		} 
                		else if (Character.isSpace((char )c))
                    		break;
                		else
                    			sb.append((char)c);
            		}
        	} 
        	catch (IOException e) 
        	{
        	}
        	vec.addElement(sb.toString());
        	return (c == -1);
    	}
}