word.java

java应用开发详解

import java.io.*;

public class Word 
{
    public static void main(String[] args) throws IOException 
    {

        //用FileReader类读文件words.txt，得到字符流
        FileReader words = new FileReader("words.txt");

        //对字符流进行翻转、检索、翻转处理
        Reader setWord = reverse(sort(reverse(words)));

        //得到一个被处理过的流的过滤流－buffered
        BufferedReader in = new BufferedReader(setWord);
       
        String input;
        
        //通过标准输出打印
        while ((input = in.readLine()) != null)
            System.out.println(input);
        in.close();
    }

    //翻转操作
    //注意：参数和返回值都用了父类
    public static Reader reverse(Reader source) throws IOException 
    {
    	
        //缓冲书数据源
        BufferedReader in = new BufferedReader(source);

        //构造一个空的管道输出流
        PipedWriter pipeOut = new PipedWriter();
        //使pipeOut的数据流入pipeIn
        PipedReader pipeIn = new PipedReader(pipeOut);
        
        PrintWriter out = new PrintWriter(pipeOut);
	
	//将数据源中的数据输入到过滤流PrintWriter－out中
	//out在构造方法中封装了pipOut，所有实际输出是pipOut
        new ReverseThread(out, in).start();

        //返回一个PipedReader
        return pipeIn;
    }

    //排序操作，过程类似reverse方法
    public static Reader sort(Reader source) throws IOException {

        BufferedReader in = new BufferedReader(source);

        PipedWriter pipeOut = new PipedWriter();
        PipedReader pipeIn = new PipedReader(pipeOut);
        PrintWriter out = new PrintWriter(pipeOut);

        new SortThread(out, in).start();

        return pipeIn;
    }
}