多线程通过管道进行线程间通信-蒲公英云

多线程通过管道进行线程间通信

小鱼儿 2022-06-10 13:26 282阅读 0赞

通过管道进行线程间通信
* 在Java语言中提供了各种各样的输入/输出流Stream，使我们能够狠方便地对数据进行操作，其中管道
流式一种特殊的流，用于在不同线程间直接传输数据。一个线程发送数据到输出管道，另一个线程
从输入管道中读数据。通过使用管道，实现不同线程间的通信。

\* 在java的JDK中提供了4个类来使线程间可以进行通信  
    1. PipedInputStream和PipedOutputStream  
    2. PipedReader和PipedWriter

字节流
* 举个栗子

     public class WriteData \{  
         public void writeMethod(PipedOutputStream out)\{  
             try\{  
                 System.out.println("write :");  
                 for(int i=0;i<300;i++)\{  
                     String outData=""+(i+1);  
                     out.write(outData.getBytes());  
                     System.out.print(outData);  
                 \}  
                 System.out.println();  
                 out.close();  
             \}catch (IOException e)\{  
                 e.printStackTrace();  
             \}  
         \}  
     \}

        public class ReadData \{  
            public void readMethod(PipedInputStream input)\{  
                try \{  
                    System.out.println("read :");  
                    byte\[\] byteArray=new byte\[20\];  
                    int readLength=input.read(byteArray);  
                    while(readLength!=-1)\{  
                        String newData=new String(byteArray,0,readLength);  
                        System.out.print(newData);  
                        readLength=input.read(byteArray);  
                    \}  
                    System.out.println();  
                    input.close();  
                \}catch (IOException e)\{  
                    e.printStackTrace();  
                \}  
            \}  
        \}  
        public class ThreadWrite extends Thread \{  
            private WriteData write;  
            private PipedOutputStream out;  
            public ThreadWrite(WriteData write,PipedOutputStream out)\{  
                super();  
                this.write=write;  
                this.out=out;  
            \}  
            @Override  
            public void run() \{  
                write.writeMethod(out);  
            \}  
        \}  
        public class ThreadRead extends Thread\{  
            private ReadData read;  
            private PipedInputStream input;  
            public ThreadRead(ReadData read,PipedInputStream input)\{  
                super();  
                this.read=read;  
                this.input=input;  
            \}  
            @Override  
            public void run() \{  
                read.readMethod(input);  
            \}  
        \}  
        public class Run \{  
            public static void main(String\[\] args)\{  
                try\{  
                    WriteData writeData=new WriteData();  
                    ReadData readData=new ReadData();  
                    PipedInputStream inputStream=new PipedInputStream();  
                    PipedOutputStream outputStream=new PipedOutputStream();  
                    outputStream.connect(inputStream);  
                    ThreadRead threadRead=new ThreadRead(readData,inputStream);  
                    threadRead.start();  
                    Thread.sleep(2000);  
                    ThreadWrite threadWrite=new ThreadWrite(writeData,outputStream);  
                    threadWrite.start();  
                \}catch (IOException e)\{  
                    e.printStackTrace();  
                \}catch (InterruptedException e)\{  
                    e.printStackTrace();  
                \}  
            \}  
        \}  
    注释：outputStream.connect(inputStream)的作用使两个Stream之间产生通信链接。  
        在没有数据被写入是，int readLength=in.read(byteArray)处于阻塞状态，直到  
        有数据被写入，才继续向下运行。

字符流
* 举个栗子

     public class WriteData \{  
         public void writeMethod(PipedWriter out)\{  
             try\{  
                 System.out.println("write :");  
                 for(int i=0;i<300;i++)\{  
                     String outData=""+(i+1);  
                     out.write(outData);  
                     System.out.print(outData);  
                 \}  
                 System.out.println();  
                 out.close();  
             \}catch (IOException e)\{  
                 e.printStackTrace();  
             \}  
         \}  
     \}  
     public class ReadData \{  
         public void readMethod(PipedReader input)\{  
             try\{  
                 System.out.println("read :");  
                 char\[\] byteArray=new char\[20\];  
                 int readLength=input.read(byteArray);  
                 while(readLength!=-1)\{  
                     String newData=new String(byteArray,0,readLength);  
                     System.out.print(newData);  
                     readLength=input.read(byteArray);  
                 \}  
                 System.out.println();  
                 input.close();  
             \}catch (IOException e)\{  
                 e.printStackTrace();  
             \}  
         \}  
     \}  
     public class ThreadWrite extends Thread\{  
         private WriteData write;  
         private PipedWriter out;  
         public ThreadWrite(WriteData write,PipedWriter out)\{  
             super();  
             this.write=write;  
             this.out=out;  
         \}

            @Override  
            public void run() \{  
                write.writeMethod(out);  
            \}  
        \}  
        public class ThreadRead extends Thread\{  
            private ReadData read;  
            private PipedReader input;  
            public ThreadRead(ReadData read,PipedReader input)\{  
                super();  
                this.read=read;  
                this.input=input;  
            \}  
            @Override  
            public void run() \{  
                read.readMethod(input);  
            \}  
        \}  
        public class Run \{  
            public static void main(String\[\] args)\{  
                try\{  
                    WriteData writeData=new WriteData();  
                    ReadData readData=new ReadData();  
                    PipedReader inputStream=new PipedReader();  
                    PipedWriter outputStream=new PipedWriter();  
                    outputStream.connect(inputStream);  
                    ThreadRead threadRead=new ThreadRead(readData,inputStream);  
                    threadRead.start();  
                    Thread.sleep(2000);  
                    ThreadWrite threadWrite=new ThreadWrite(writeData,outputStream);  
                    threadWrite.start();  
                \}catch (IOException e)\{  
                    e.printStackTrace();  
                \}catch (InterruptedException e)\{  
                    e.printStackTrace();  
                \}  
            \}  
        \}  
        \* 和字节流类似，就是输入输出会更加方便。