NIO

港控/mmm° 2022-12-07 12:44 95阅读 0赞

服务端

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.*;
    import java.util.Iterator;
    
    public class MyServer { 
    
    
        private int size = 1024;
    
        private ServerSocketChannel serverSocketChannel;
    
        private ByteBuffer  byteBuffer;
    
        private Selector selector;
    
        private int remoteClientNum = 0;
    
        public MyServer(int port) throws IOException { 
            initChannel(port);
        }
    
        public void initChannel(int port) throws IOException { 
            serverSocketChannel = ServerSocketChannel.open();
            serverSocketChannel.configureBlocking(false);
            serverSocketChannel.bind(new InetSocketAddress(port));
            selector =Selector.open();
            serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
            byteBuffer = ByteBuffer.allocate(size);
    
        }
    
        private void listener() throws IOException { 
            while(true){ 
                int select = selector.select();
                if(select==0){ 
                    continue;
                }
    
                Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
                while(iterator.hasNext()){ 
                    SelectionKey key = iterator.next();
                    if(key.isAcceptable()){ 
                        ServerSocketChannel server = (ServerSocketChannel) key.channel();
                        SocketChannel channel = server.accept();
                        registerChannel(selector,channel,SelectionKey.OP_READ);
                        remoteClientNum++;
                        System.out.println("客户端连接数"+remoteClientNum);
                        write(channel,"hello client".getBytes());
    
                    }
                    if(key.isReadable()){ 
                        read(key);
                    }
                    iterator.remove();
                }
            }
        }
    
    
        private void registerChannel(Selector selector,SocketChannel socketChannel,int opRead) throws IOException { 
            if(socketChannel == null){ 
                return;
            }
            socketChannel.configureBlocking(false);
            socketChannel.register(selector,opRead);
        }
    
    
        private void write(SocketChannel socketChannel,byte[] writeDate) throws IOException { 
    
            byteBuffer.clear();
            byteBuffer.put(writeDate);
            byteBuffer.flip();
            socketChannel.write(byteBuffer);
        }
    
        private void read(SelectionKey key) throws IOException { 
            SocketChannel socketChannel = (SocketChannel)key.channel();
            int count;
            byteBuffer.clear();
    
            while ((count=socketChannel.read(byteBuffer))>0){ 
                byteBuffer.flip();
                while (byteBuffer.hasRemaining()){ 
                    System.out.print((char) byteBuffer.get());
    
                }
                byteBuffer.clear();
    
            }
    
           if(count < 0 ){ 
               socketChannel.close();
           }
    
        }
    
        public static void main(String[] args) throws IOException { 
            MyServer myServer = new MyServer(9999);
            myServer.listener();
        }
    }

客户端

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.SocketChannel;
    
    public class MyClient { 
        private int  size = 1024;
        private ByteBuffer  byteBuffer;
        private SocketChannel socketChannel;
        public void connectServer() throws IOException { 
            socketChannel = SocketChannel.open();
            socketChannel.connect(new InetSocketAddress("127.0.0.1",9999));
            socketChannel.configureBlocking(false);
            byteBuffer = ByteBuffer.allocate(size);
            receive();
    
        }
    
        private void receive() throws IOException { 
            while(true){ 
                byteBuffer.clear();
                int count;
    
                while ((count=socketChannel.read(byteBuffer))>0){ 
                    byteBuffer.flip();
                    while (byteBuffer.hasRemaining()){ 
                        System.out.print((char)byteBuffer.get());
                    }
                    send2Server("sayhi".getBytes());
                    byteBuffer.clear();
                }
            }
        }
    
        private void send2Server(byte[] bytes) throws IOException { 
            byteBuffer.clear();
            byteBuffer.put(bytes);
            byteBuffer.flip();
            socketChannel.write(byteBuffer);
    
        }
    
        public static void main(String[] args) throws IOException { 
            new MyClient().connectServer();
        }
    }