Springboot 搭建 WebSocket

需求

需求？开玩笑，干就完了！

环境

1. IntelliJ IDEA 2021.3.2
2. springboot 2.3.3.RELEASE
3. spring-boot-starter-websocket:2.7.0
4. postman

开搞

前提：基于 gradle 搭建

• application.yml：

server:
  port: 80 // 配置访问端口即可

• build.gradle

plugins {
    id 'org.springframework.boot' version '2.3.3.RELEASE'
    id 'java'
}
repositories {
     mavenCentral()
     // 配置阿里镜像，快的飞起
    maven { url 'https://plugins.gradle.org/m2/' }
    maven { url 'https://maven.aliyun.com/nexus/content/repositories/google' }
    maven { url 'https://maven.aliyun.com/nexus/content/groups/public/' }
    maven { url 'https://maven.aliyun.com/nexus/content/repositories/jcenter'}
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-websocket:2.7.0'
}

• WebSocketApplication.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;

@ComponentScan(basePackages = "这里改成你Component所在的包")
// 因为只做 WebSocket，这里过滤掉数据源注入
@SpringBootApplication(exclude={DataSourceAutoConfiguration.class, HibernateJpaAutoConfiguration.class})
public class WebSocketApplication {

    public static void main(String[] args) {
        SpringApplication.run(WebSocketApplication.class, args);
    }

}

• WebSocketConfigurator.java

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

import javax.websocket.server.ServerEndpointConfig;

public class WebSocketConfigurator extends ServerEndpointConfig.Configurator implements ApplicationContextAware {

    private static volatile BeanFactory context;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        WebSocketConfigurator.context = applicationContext;
    }

    @Override
    public <T> T getEndpointInstance(Class<T> clazz) throws InstantiationException {
        return context.getBean(clazz);
    }
}

• WebSocketConfig.java

package com.zy.ws;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;

@Configuration
public class WebSocketConfig {

    /**
     * 这个 Bean 会自动注册使用注解 @ServerEndpoint 注解生命的 websocket
     * @return
     */
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        return new ServerEndpointExporter();
    }

    /**
     * 这个 Bean 让 Spring 能够捕获到请求
     * 这里可能说的不对
     * @return
     */
    @Bean
    public WebSocketConfigurator webSocketConfigurator() {
        return new WebSocketConfigurator();
    }

}

• WebSocketServer.java

import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArrayList;

@Component
// 监听指定连接
@ServerEndpoint(value = "/ws/{username}", configurator = WebSocketConfigurator.class)
public class WebSocketServer {

    // 实例化一个 websocket 的 session
    private Session session;

    @OnOpen
    public void onOpen(@PathParam("username") String username, Session session) {
        System.out.println("有连接进来了：" + username);
    }

    @OnMessage
    public void onMessage(String message) {
        System.out.println(String.format("接收到来自客户端的消息：【%s】", message));
    }

    @OnClose
    public void onClose(@PathParam("username") String username) {
        System.out.println("有连接关闭了：" + username);
    }

    @OnError
    public void onError(Throwable e) {
        System.out.println("出问题啦！！！");
    }

}

后台部分写到这里启动程序基本没什么问题了，idea 直接启动

• postman 连接
  
• 后端接收
  
• postman 发送消息
  
• 后端接收
  

完结晒花