BIO、NIO、AIO之IO

悠悠 2023-07-06 13:17 12阅读 0赞

## 一、BIO ##

import java.io.IOException;
    import java.net.ServerSocket;
    import java.net.Socket;
    
    /**
     *   阻塞式服务端通信
     * @author zc
     *
     */
    public class BIOServer {
    	
    	public static void main(String[] args) throws IOException {
    		ServerSocket  serverSocket = new ServerSocket(9000);
    		while(true) {
    			
    			System.out.println("服务器端等待连接...");
    			//阻塞方法
    			Socket socket = serverSocket.accept();
    			System.out.println("有客户端连接....");
    			handler(socket);
    			
    		}
    		
    	}
    
    	private static void handler(Socket socket) throws IOException {
    		//获得当前线程的id
    		System.out.println(Thread.currentThread().getId());
    		byte[] bytes = new byte[1024];
    		System.out.println("准备read...");
    		int read =socket.getInputStream().read(bytes);
    		System.out.println("read完毕...");
    		if(read!=-1) {
    		  System.out.println("接收到客户端的数据"+ new String(bytes,0,read));	
    		  System.out.println("thread id ="+Thread.currentThread().getId());
    		}
    		socket.getOutputStream().write("HelloClient".getBytes());
    		socket.getOutputStream().flush();
    	}
    
    }

import java.io.IOException;
    import java.net.Socket;
    import java.net.UnknownHostException;
    
    /**
     * 阻塞式客户端通信
     * @author zc
     *
     */
    public class BIOClient {
          
    	public static void main(String[] args) throws UnknownHostException, IOException {
    		Socket socket  = new Socket("127.0.0.1",9000);
    		//向服务端发送数据
    		socket.getOutputStream().write("HelloServer".getBytes());
    		socket.getOutputStream().flush();
    		System.out.println("向服务器端发送数据结束");
    		
    		//接收服务器端传回来的的数据
    		byte[] bytes =new byte[1024];
    		socket.getInputStream().read(bytes);
    		System.out.println("接收到服务器端的数据: "+ new String(bytes));
    	    //关闭socket连接
    		socket.close();
    	}
    }

## 二、NIO ##

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.SelectionKey;
    import java.nio.channels.Selector;
    import java.nio.channels.ServerSocketChannel;
    import java.nio.channels.SocketChannel;
    import java.util.Iterator;
    
    public class NIOServer {
    	
    	public static void main(String[] args) throws IOException {
    		
    		ServerSocketChannel ssc = ServerSocketChannel.open();
    		
    		ssc.configureBlocking(false);
    		ssc.socket().bind(new InetSocketAddress(9000));
    		
    		//创建一个选择器 selector
    		Selector selector = Selector.open();
    		
    		ssc.register(selector,SelectionKey.OP_ACCEPT);
    		
    		while(true) {
    			
    			System.out.println("等待事件的发生....");
    			
    			int select = selector.select();
    			System.out.println("有事情发生了....");
    			
    			Iterator<SelectionKey> it= selector.selectedKeys().iterator();
    			
    			while(it.hasNext()) {
    				SelectionKey key = it.next();
    				it.remove();
    				hanle(key);
    				
    			}
    			
    		}
    	}
    
    	private static void hanle(SelectionKey key) throws IOException {
    		// TODO Auto-generated method stub
    		if(key.isAcceptable()) {
    			System.out.println("有客户端连接事件发生了....");
    			ServerSocketChannel ssc= (ServerSocketChannel) key.channel();
    			
    			SocketChannel sc = ssc.accept();
    			sc.configureBlocking(false);
    			sc.register(key.selector(),SelectionKey.OP_READ);
    		}else if(key.isReadable()) {
    			
    			System.out.println("有客户端可读事件发生了....");
    			SocketChannel sc=(SocketChannel) key.channel();
    			ByteBuffer buffer = ByteBuffer.allocate(1024);
    			int len =sc.read(buffer);
    			if(len!=-1) {
    				System.out.println("客户端发送的数据"+ new String(buffer.array(),0,len));
    			}
    			ByteBuffer bufferToWrite =ByteBuffer.wrap("HelloClient".getBytes());
    			sc.write(bufferToWrite);
    			key.interestOps(SelectionKey.OP_READ| SelectionKey.OP_WRITE);
    		}else if(key.isWritable()) {
    			SocketChannel sc=(SocketChannel) key.channel();
    			System.out.println("客户端write事件发生了");
    			key.interestOps(SelectionKey.OP_READ);
    			
    		}
    		
    	}
    
    }

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.SelectionKey;
    import java.nio.channels.Selector;
    import java.nio.channels.SocketChannel;
    import java.util.Iterator;
    
    public class NIOClient {
        private Selector selector;
    	public static void main(String[] args) throws IOException {
    		
    		NIOClient client =new NIOClient();
    		client.initClient("127.0.0.1",9000);
    		client.connect();
    		
    	}
    
    	private void connect() throws IOException {
    		// TODO Auto-generated method stub
    		 // 轮询访问selector
            while (true) {
                selector.select();
                // 获得selector中选中的项的迭代器
                Iterator<SelectionKey> it = this.selector.selectedKeys().iterator();
                while (it.hasNext()) {
                    SelectionKey key = (SelectionKey) it.next();
                    // 删除已选的key,以防重复处理
                    it.remove();
                    // 连接事件发生
                    if (key.isConnectable()) {
                        SocketChannel channel = (SocketChannel) key.channel();
                        // 如果正在连接，则完成连接
                        if (channel.isConnectionPending()) {
                            channel.finishConnect();
                        }
                        // 设置成非阻塞
                        channel.configureBlocking(false);
                        //在这里可以给服务端发送信息哦
                        ByteBuffer buffer = ByteBuffer.wrap("HelloServer".getBytes());
                        channel.write(buffer);
                        //在和服务端连接成功之后，为了可以接收到服务端的信息，需要给通道设置读的权限。
                        channel.register(this.selector, SelectionKey.OP_READ);                                            // 获得了可读的事件
                    } else if (key.isReadable()) {
                        read(key);
                    }
                }
            }
        }
    
        /**
         * 处理读取服务端发来的信息 的事件
         *
         * @param key
         * @throws IOException
         */
        public void read(SelectionKey key) throws IOException {
            //和服务端的read方法一样
            // 服务器可读取消息:得到事件发生的Socket通道
            SocketChannel channel = (SocketChannel) key.channel();
            // 创建读取的缓冲区
            ByteBuffer buffer = ByteBuffer.allocate(1024);
            int len = channel.read(buffer);
            if (len != -1) {
                System.out.println("客户端收到信息：" + new String(buffer.array(), 0, len));
            }
        }
    	
    
    	private void initClient(String ip, int port) throws IOException {
    		// TODO Auto-generated method stub
    		SocketChannel channel =SocketChannel.open();
    		channel.configureBlocking(false);
    		this.selector =Selector.open();
    		channel.connect(new InetSocketAddress(ip,port));
    		channel.register(selector, SelectionKey.OP_CONNECT);
    		
    	}
    }

## 三、AIO ##

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.AsynchronousServerSocketChannel;
    import java.nio.channels.AsynchronousSocketChannel;
    import java.nio.channels.CompletionHandler;
    
    /**
     *  异步服务端接口
     * @author zc
     *
     */
    public class AIOServer {
    
    	  public static void main(String[] args) throws IOException, InterruptedException {
    		
    		 final AsynchronousServerSocketChannel  serverChannel= AsynchronousServerSocketChannel.open().bind(new InetSocketAddress(9000));
    		 
    		 serverChannel.accept(null, new CompletionHandler<AsynchronousSocketChannel,Object>() {
    
    			@Override
    			public void completed(AsynchronousSocketChannel socketChannel, Object arg1) {
    				// TODO Auto-generated method stub
    				try {
    				
    					System.out.println(socketChannel.getRemoteAddress());
    					ByteBuffer buffer =ByteBuffer.allocate(1024);
    					socketChannel.read(buffer,buffer,new CompletionHandler<Integer,ByteBuffer>(){
    
    						@Override
    						public void completed(Integer result, ByteBuffer attachment) {
    							// TODO Auto-generated method stub
    							buffer.flip();
    							System.out.println(new String(buffer.array(),0,result));
    							socketChannel.write(ByteBuffer.wrap("HelloClient".getBytes()));
    						}
    
    						@Override
    						public void failed(Throwable exc, ByteBuffer attachment) {
    							// TODO Auto-generated method stub
    							exc.printStackTrace();
    						}
    						
    					});
    				} catch (IOException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    			}
    
    			@Override
    			public void failed(Throwable arg0, Object arg1) {
    				// TODO Auto-generated method stub
    				arg0.printStackTrace();
    			}
    			 
    		 });
    		 
    		 Thread.sleep(Integer.MAX_VALUE);
    		 
    	}
    	
    }

import java.io.IOException;
    import java.net.InetSocketAddress;
    import java.nio.ByteBuffer;
    import java.nio.channels.AsynchronousSocketChannel;
    import java.util.concurrent.ExecutionException;
    
    /**
     * 异步调用客户端
     * @author zc
     *
     */
    public class AIOClient {
    	  public static void main(String...args) throws IOException, InterruptedException, ExecutionException {
    		
    		AsynchronousSocketChannel socketChannel =AsynchronousSocketChannel.open();
    	    socketChannel.connect(new InetSocketAddress("127.0.0.1",9000)).get();
    	    socketChannel.write(ByteBuffer.wrap("HelloServer".getBytes()));
    	    ByteBuffer buffer =ByteBuffer.allocate(1024);
    	    Integer len =socketChannel.read(buffer).get();
    	    if(len != -1) {
    	    	System.out.println("客户端接受消息"+ new String(buffer.array(),0,len));
    	    }
    	}
    	
    
    }

![在这里插入图片描述][format_png_pic_center]  
[原文][Link 1]

[format_png_pic_center]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9pbWcyMDE4LmNuYmxvZ3MuY29tL2ktYmV0YS8xNTA2NTk3LzIwMjAwMi8xNTA2NTk3LTIwMjAwMjA5MTcwNDQ4MTI5LTY3MzY0MDkxOS5wbmc?x-oss-process=image/format,png#pic_center
[Link 1]: https://www.cnblogs.com/cxiaocai/p/12303633.html