多线程（六）~通过管道进行线程之间的通信：字节流、字符流

学习文件IO等操作的时候用到了流，例如文件上传的时候是将文件转换成二进制的流传到服务器端。

在不同线程之间通信也是用到了对管道流的操作，在java中提供了4个类来操作管道流(pipeStream)：

    1).PipedInputStream和PipedOutputStream

    2).PipedReader和PipedWriter

字节流Demo：

①.写数据、读数据

1. package com.multiThread.bean;
3. import java.io.PipedOutputStream;
5. publicclassWriteData{
7. publicvoid writeMethod(PipedOutputStream outputStream){
8. try{
9. System.out.println("write:");
10. for(int i =0;i<100;i++){
11. String outData =""+(i +1);
12. outputStream.write(outData.getBytes());
13. System.out.print(outData);
14. }
15. System.out.println();
16. outputStream.close();
17. }catch(Exception e){
18. e.printStackTrace();
19. }
20. }
21. }

1. package com.multiThread.bean;
3. import java.io.PipedInputStream;
5. publicclassReadData{
7. publicvoid readMethod(PipedInputStream pipedInputStream){
8. try{
9. System.out.println("read:");
10. byte[] b =newbyte[20];
11. int readLength = pipedInputStream.read(b);
12. while(readLength !=-1){
13. String newData =newString(b,0,readLength);
14. System.out.print(newData);
15. readLength = pipedInputStream.read(b);
16. }
17. System.out.println();
18. pipedInputStream.close();
19. }catch(Exception e){
20. e.printStackTrace();
21. }
22. }
24. }

②.写数据线程、读数据线程

1. package com.multiThread.thread;
3. import java.io.PipedOutputStream;
5. import com.multiThread.bean.WriteData;
7. publicclassWriteThreadimplementsRunnable{
9. privatePipedOutputStream pipedOutputStream;
10. privateWriteData writeData;
12. publicWriteThread(PipedOutputStream pipedOutputStream,WriteData writeData){
13. this.pipedOutputStream = pipedOutputStream;
14. this.writeData = writeData;
15. }
16. @Override
17. publicvoid run(){
18. writeData.writeMethod(pipedOutputStream);
19. }
20. }

1. package com.multiThread.thread;
3. import java.io.PipedInputStream;
5. import com.multiThread.bean.ReadData;
7. publicclassReadThreadimplementsRunnable{
9. privatePipedInputStream pipedInputStream;
10. privateReadData readData;
12. publicReadThread(PipedInputStream inputStream,ReadData readData){
13. this.pipedInputStream = inputStream;
14. this.readData = readData;
15. }
17. @Override
18. publicvoid run(){
19. readData.readMethod(pipedInputStream);
20. }
22. }

③.测试

1. package com.multiThread.test;
3. import java.io.PipedInputStream;
4. import java.io.PipedOutputStream;
5. import com.multiThread.bean.ReadData;
6. import com.multiThread.bean.WriteData;
7. import com.multiThread.thread.ReadThread;
8. import com.multiThread.thread.WriteThread;
10. publicclassPipeTest{
11. publicstaticvoid main(String[] args){
12. try{
13. WriteData writeData =newWriteData();
14. ReadData readData =newReadData();
16. PipedInputStream inputStream =newPipedInputStream();
17. PipedOutputStream outputStream =newPipedOutputStream();
19. inputStream.connect(outputStream);
20. // outputStream.connect(inputStream);
24. ReadThread readThread =newReadThread(inputStream, readData);
25. Thread t2 =newThread(readThread);
26. t2.start();
27. Thread.sleep(2000);
29. WriteThread writeThread =newWriteThread(outputStream, writeData);
30. Thread t1 =newThread(writeThread);
31. t1.start();
32. }catch(Exception e){
33. e.printStackTrace();
34. }
36. }
37. }

执行结果：

1. read:
2. write:
3. 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100
4. 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100

 

除了支持字节流之外，还可以使用字符流

只需要把读数据写数据的操作由“PipedInputStream和PipedOutputStream”换成“PipedReader和PipedWriter”即可，其他地方实现逻辑不变。这块就不做例子了。

 

来自为知笔记(Wiz)