NIO之同步阻塞

文章目录

NIO之同步阻塞
前言
一、POM包引入
二、同步非阻塞
总结

前言

为了深入理解java中NIO的同步非阻塞功能，本文先从同步阻塞思想开始，了解NIO的基本原理。

一、POM包引入

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.5</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>

二、同步非阻塞

1.服务端接受消息

1.1服务端代码

/**
     * 1. 服务端等待客户端建立连接
     * 2. 服务端接受客户端的数据并打印
     */
    public static void main(String[] args) throws IOException {
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.bind(new InetSocketAddress(8080));
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        log.info("Connecting...");
        SocketChannel channel = serverSocketChannel.accept();
        log.info("Connected, channel={}", channel);
        while(true) {
            log.info("Before read, channel={}", channel);
            channel.read(buffer);
            buffer.flip();
            show(buffer);
            buffer.clear();
            log.info("After read, channel={}", channel);
        }
    }

1.2客户端代码

/**
     * 1. 客户端主动和服务端建立连接
     * 2. 客户端发送数据给服务端
     */
    public static void main(String[] args) throws IOException {
        SocketChannel channel = SocketChannel.open();
        channel.connect(new InetSocketAddress("localhost", 8080));
        channel.write(Charset.defaultCharset().encode("Hello world\n"));
        channel.write(Charset.defaultCharset().encode("My name is lei\n"));
        channel.close();
    }

2.服务端推送消息

2.1服务端代码

代码如下（示例）：

/**
     * 1. 服务端等待客户端建立连接
     * 2. 服务端推送数据给客户端
     */
    public static void main(String[] args) throws IOException {
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.bind(new InetSocketAddress(8080));
        log.info("Connecting...");
        SocketChannel channel = serverSocketChannel.accept();
        log.info("Connected, channel={}", channel);
        channel.write(Charset.defaultCharset().encode("Hi"));
        channel.close();
    }

2.1客户端代码

代码如下（示例）：

/**
     * 1. 客户端主动和服务端建立连接
     * 2. 客户端接受服务端的数据并打印
     */
    public static void main(String[] args) throws IOException {
        SocketChannel channel = SocketChannel.open();
        channel.connect(new InetSocketAddress("localhost", 8080));
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        while(true) {
            channel.read(buffer);
            buffer.flip();
            show(buffer);
            buffer.clear();
        }
    }