什么是管道流，能不能举个最简单的例子并解释一下

PipeInputStream and PipeOutStream are used to communicate between Threads. One Thread write something to a pipe,the other thread read it from the same pipe.import java.io.*;  
 
    
 
  public class PipedBytes extends Object {  
 
      public static void writeStuff(OutputStream rawOut) {  
 
          try {  
 
              DataOutputStream out = new DataOutputStream(  
 
                      new BufferedOutputStream(rawOut));  
 
        
 
              int[] data = { 82, 105, 99, 104, 97, 114, 100, 32,   
 
                            72, 121, 100, 101 };  
 
    
 
              for ( int i = 0; i < data.length; i++ ) {  
 
                  out.writeInt(data[i]);  
 
              }  
              out.flush();  
 
              out.close();  
 
          } catch ( IOException x ) {  
 
              x.printStackTrace();  
 
          }  
 
      }  
       public static void readStuff(InputStream rawIn) {  
 
          try {  
 
              DataInputStream in = new DataInputStream(  
 
                      new BufferedInputStream(rawIn));  
 
    
 
              boolean eof = false;  
 
              while ( !eof ) {  
 
                  try {  
 
                      int i = in.readInt();  
                      System.out.println(“just read: “ + i);  
 
                  } catch ( EOFException eofx ) {  
 
                      eof = true;  
 
                  }  
 
              }  
 
    
 
              System.out.println(“Read all data from the pipe”);  
 
          } catch ( IOException x ) {  
 
              x.printStackTrace();  
 
          }  
       }  
 
    
 
      public static void main(String[] args) {  
 
          try {  
 
              final PipedOutputStream out =   
 
                      new PipedOutputStream();  
 
    
              final PipedInputStream in =   
                       new PipedInputStream(out);  
 
    
               Runnable runA = new Runnable() {  
 
                      public void run() {  
 
                          writeStuff(out);  
 
                      }  
 
                  };  
 
    
 
              Thread threadA = new Thread(runA, “threadA”);  
 
              threadA.start();  
 
    
 
              Runnable runB = new Runnable() {  
 
                      public void run() {  
 
                          readStuff(in);  
 
                      }  
                  };  
 
    
 
              Thread threadB = new Thread(runB, “threadB”);  
              threadB.start();  
 
           } catch ( IOException x ) {  
 
               x.printStackTrace();  
 
           }  
 
       }  
 
   }