NIO（四）--DatagramChannel&Pipe管道

NIO与Pipe管道详解

最新推荐文章于 2023-01-31 14:03:16 发布

原创最新推荐文章于 2023-01-31 14:03:16 发布 · 249 阅读

0 ·

CC 4.0 BY-SA版权

NIO 专栏收录该内容

12 篇文章

订阅专栏

本文深入探讨了Java NIO中的DatagramChannel非阻塞模式的实现，包括发送与接收数据包的过程，并详细介绍了Pipe管道的使用方法，演示了如何通过Pipe进行数据的双向传输。

一、DatagramChannel

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.DatagramChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.util.Date;
import java.util.Iterator;
import java.util.Scanner;

import org.junit.Test;

public class TestNonBlockingNIO2 {
	
	@Test
	public void send() throws IOException{
		DatagramChannel dc = DatagramChannel.open();
		
		dc.configureBlocking(false);
		
		ByteBuffer buf = ByteBuffer.allocate(1024);
		
		Scanner scan = new Scanner(System.in);
		
		while(scan.hasNext()){
			String str = scan.next();
			buf.put((new Date().toString() + ":\n" + str).getBytes());
			buf.flip();
			dc.send(buf, new InetSocketAddress("127.0.0.1", 9898));
			buf.clear();
		}
		
		dc.close();
	}
	
	@Test
	public void receive() throws IOException{
		DatagramChannel dc = DatagramChannel.open();
		
		dc.configureBlocking(false);
		
		dc.bind(new InetSocketAddress(9898));
		
		Selector selector = Selector.open();
		
		dc.register(selector, SelectionKey.OP_READ);
		
		while(selector.select() > 0){
			Iterator<SelectionKey> it = selector.selectedKeys().iterator();
			
			while(it.hasNext()){
				SelectionKey sk = it.next();
				
				if(sk.isReadable()){
					ByteBuffer buf = ByteBuffer.allocate(1024);
					
					dc.receive(buf);
					buf.flip();
					System.out.println(new String(buf.array(), 0, buf.limit()));
					buf.clear();
				}
			}
			it.remove();
		}
	}
}

二、Pipe管道

import org.junit.Test;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.Pipe;

public class TestPipe {
    @Test
    public void test1() throws IOException {
        //1.获取管道
        Pipe pipe = Pipe.open();

        //2.将缓冲区中的数据写入管道
        ByteBuffer buf = ByteBuffer.allocate(1024);

        Pipe.SinkChannel sinkChannel = pipe.sink();

        buf.put("通过单向管道发送数据".getBytes());
        buf.flip();
        sinkChannel.write(buf);


        //3.读取缓冲区的数据
        Pipe.SourceChannel sourceChannel = pipe.source();
        buf.flip();
        int len = sourceChannel.read(buf);
        System.out.println(new String(buf.array(), 0, len));
        
        sourceChannel.close();
        sinkChannel.close();
    }
}