管道流（PipedStream）可以用于不同线程间直接传送数据。
一个线程发送数据到输出管道，另一个线程从输入管道中读取数据。通过使用管道，实现不同线程间的通信，而无须借助于类似临时文件之类的东西。
package thread.communicate; import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream; /*2015-11-19*/
public class CommunicateWithPipedStream {
public static void main(String[] args) {
try {
PipedOutputStream out = new PipedOutputStream();
DataWriter writer = new DataWriter(out);
PipedInputStream in = new PipedInputStream();
DataReader reader = new DataReader(in);
// out.connect(in);
in.connect(out);
new Thread(writer, "Writer").start();
new Thread(reader, "Reader").start();
} catch (Exception e) {
e.printStackTrace();
} }
} class DataWriter implements Runnable {
private PipedOutputStream _out; public DataWriter(PipedOutputStream out) {
super();
this._out = out;
} @Override
public void run() {
write();
} public void write() {
System.out.println(Thread.currentThread() + "Start write....");
try {
for (int i = 0; i < 20; i++) {
String outStr = "" + (i + 1);
System.out.println(Thread.currentThread() + outStr);
_out.write(outStr.getBytes());
}
_out.close(); } catch (IOException e) {
e.printStackTrace();
} } } class DataReader implements Runnable { private PipedInputStream _in; public DataReader(PipedInputStream in) {
_in = in;
} @Override
public void run() {
read();
} public void read() {
try {
System.out.println(Thread.currentThread() + "Start read....");
byte[] byteArray = new byte[20];
int readLength = _in.read(byteArray);
while (readLength != -1) {
String newData = new String(byteArray, 0, readLength);
System.out.println(Thread.currentThread() + newData);
readLength = _in.read(byteArray);
}
System.out.println();
_in.close();
} catch (Exception e) {
e.printStackTrace();
}
} }
输出：
Thread[Writer,5,main]Start write....
Thread[Writer,5,main]1
Thread[Reader,5,main]Start read....
Thread[Writer,5,main]2
Thread[Reader,5,main]1
Thread[Reader,5,main]2
Thread[Writer,5,main]3
Thread[Writer,5,main]4
Thread[Writer,5,main]5
Thread[Writer,5,main]6
Thread[Writer,5,main]7
Thread[Writer,5,main]8
Thread[Writer,5,main]9
Thread[Writer,5,main]10
Thread[Writer,5,main]11
Thread[Writer,5,main]12
Thread[Writer,5,main]13
Thread[Writer,5,main]14
Thread[Writer,5,main]15
Thread[Writer,5,main]16
Thread[Writer,5,main]17
Thread[Writer,5,main]18
Thread[Writer,5,main]19
Thread[Writer,5,main]20
Thread[Reader,5,main]34567891011121314151
Thread[Reader,5,main]617181920