简单的springboot 编写Socket服务接口

1.需求

我们项目中有部分老接口为票据接口，其中实现为java socket形式进行实现，但是其中大部分信息都是原始公司封装的包进行实现的，想要修改非常费劲，所以此处简单了解了一下socket，自己简单的编写了两个测试接口，方便以后如果需要自己添加socket接口，可以快速编写。

2. 简单实现

编写的接口为测试接口，整体结构相对简单，主要就是客户端发起一个请求，请求信息前6位为请求串长度，其余为请求的请求体，发送信息到服务端后，服务端使用线程池异步处理信息，最终返回处理之后的响应信息，客户端则接收响应信息，同样的步骤处理响应信息，前6位为响应信息长度，然后解析响应信息即可，因为为简单案例，所以没有进行数据通信加密。

2.1 客户端实现

客户端代码相对简单，直接写入到controller当中了，具体实现代码如下：

package cn.git.controller;

import cn.git.entity.Product;
import cn.git.socket.SocketUtil;
import com.alibaba.fastjson.JSONObject;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.math.BigDecimal;
import java.net.Socket;

/**
 * @description: Socket测试controller
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2023-03-20
 */
@RestController
@RequestMapping("/socket")
public class SocketController {

	/**
	 * 异步发送200个请求，模拟多用户
	 */
    @GetMapping("/client")
    public String client() {
    	// 异步发送200个请求，模拟多用户
        for (int i = 0; i < 200; i++) {
            int finalI = i;
            new Thread(()-> {
                try {
                    // 创建Socket对象
                    Socket socket = new Socket("localhost", 7777);
                    // 设置超时时间
                    socket.setSoTimeout(60000);

                    // 测试产品
                    Product product = new Product();
                    product.setAmount(new BigDecimal(finalI));
                    product.setCycle(12);
                    product.setEndTime("2018-08-08");
                    product.setName("test");
                    product.setRate(new BigDecimal(1));
                    product.setRaised(new BigDecimal(0));

                    // 拼接请求报文
                    String message = JSONObject.toJSONString(product);
                    String reqLengthStr = SocketUtil.leftFixedZero(6, message.length());

                    // 发送请求报文
                    PrintStream out = new PrintStream(socket.getOutputStream());
                    out.println(reqLengthStr.concat(message));

                    // 获取服务端返回的消息长度信息
                    BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                    char[] lengthByte = new char[6];
                    in.read(lengthByte);
                    String rspLengthStr = new String(lengthByte);
                    int responseLength = Integer.parseInt(rspLengthStr);

                    // 获取服务端返回的消息体信息
                    char[] responseByte = new char[responseLength];
                    in.read(responseByte);
                    String responseBody = new String(responseByte);

                    // 打印返回结果
                    System.out.println("返回结果为 : ".concat(responseBody));
                    socket.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }).start();
        }

        return "处理成功啦";
    }

}

2.2 服务端代码

服务端代码相对复杂一些，主要有socket服务初始化，公共线程池，工具类以及接口处理handle类。具体实现如下：

socket初始化类

package cn.git.socket;

import cn.git.mapper.ProductMapper;
import cn.git.socket.handler.SocketHandler;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @description: socket接口入口信息
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2023-03-20
 */
@Slf4j
@Component
public class CustomSocketServer {

    @Autowired
    private ProductMapper productMapper;
	
	/**
	 * 初始化调用接口
	 * 
	 * 异步启动socket监听服务，端口 7777
	 */
    @PostConstruct
    public void socketServerInit() throws IOException {
        new Thread(() -> {
            try {
                // 监听7777端口
                log.info("开始启动socket服务信息，端口监听 7777");
                ServerSocket serverSocket = new ServerSocket(7777);

                // 循环监听
                while (true) {
                    log.info("等待客户端连接...");
                    Socket clientSocket = serverSocket.accept();
                    ThreadPoolUtil.THREAD_POOL.execute(
                        // 构建handler
                        SocketHandler.builder().clientSocket(clientSocket).productMapper(productMapper).build()
                    );
                    log.info("客户端连接成功，当前连接数：{}", ThreadPoolUtil.THREAD_POOL.getActiveCount());
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }).start();
    }
}

通用线程池相关类
自定义线程池工厂实现如下

package cn.git.socket;

import cn.hutool.core.util.StrUtil;

import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * 自定义线程池工厂
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2021-12-25
 */
public class OnlineThreadFactory implements ThreadFactory {

    /**
     * 自增线程序号
     */
    private final AtomicInteger threadNumber = new AtomicInteger(1);

    /**
     * 线程名称前缀
     */
    private final String threadNamePrefix;

    /**
     * 构造方法
     * @param threadNamePrefix 方法前缀
     */
    public OnlineThreadFactory(String threadNamePrefix) {
        this.threadNamePrefix = threadNamePrefix.concat(StrUtil.DASHED);
    }

    /**
     * Constructs a new {@code Thread}.  Implementations may also initialize
     * priority, name, daemon status, {@code ThreadGroup}, etc.
     * @param runnable a runnable to be executed by new thread instance
     * @return constructed thread, or {@code null} if the request to
     * create a thread is rejected
     */
    @Override
    public Thread newThread(Runnable runnable) {
        // 设置线程池名称
        Thread thread = new Thread(runnable , threadNamePrefix.concat(StrUtil.toString(threadNumber.getAndIncrement())));

        // 设置守护线程
        if (thread.isDaemon()) {
            thread.setDaemon(false);
        }

        // 同意设置程默认优先级 5
        if (thread.getPriority() != Thread.NORM_PRIORITY) {
            thread.setPriority(Thread.NORM_PRIORITY);
        }
        return thread;
    }
}

线程池工具类

package cn.git.socket;

import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * @description: 线程池工具类
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2022-08-16 10:58:07
 */
public class ThreadPoolUtil {

    /**
     * 线程池线程名称
     */
    private static final String DICS_THREAD_POOL_PREFIX = "DICS-SOCKET";

    /**
     * 超时时间 单位毫秒
     */
    private static final int REQ_TIME_OUT = 10 * 1000;

    /**
     * 阻塞队列大小
     */
    private static final int QUEUE_SIZE = 200;

    /**
     * 核心线程池数量
     */
    private static final int CORE_THREAD_NUM = 5;

    /**
     * 最大线程池数量
     */
    private static final int MAX_THREAD_NUM = 20;

    /**
     * 线程池构造参数
     */
    public static ThreadPoolExecutor THREAD_POOL = new ThreadPoolExecutor(CORE_THREAD_NUM,
            MAX_THREAD_NUM,
            REQ_TIME_OUT,
            TimeUnit.MILLISECONDS,
            new LinkedBlockingQueue<>(QUEUE_SIZE),
            new OnlineThreadFactory(DICS_THREAD_POOL_PREFIX));
}

业务处理handle类

package cn.git.socket.handler;

import cn.git.entity.Product;
import cn.git.mapper.ProductMapper;
import cn.git.socket.SocketUtil;
import cn.hutool.core.util.IdUtil;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import lombok.*;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

/**
 * @description: socket请求处理类
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2023-03-20
 */
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class SocketHandler implements Runnable {

    /**
     * 订单信息mapper
     */
    private ProductMapper productMapper;

    /**
     * 客户端socket
     */
    private Socket clientSocket;

    /**
     * When an object implementing interface <code>Runnable</code> is used
     * to create a thread, starting the thread causes the object's
     * <code>run</code> method to be called in that separately executing
     * thread.
     * <p>
     * The general contract of the method <code>run</code> is that it may
     * take any action whatsoever.
     *
     * @see Thread#run()
     */
    @SneakyThrows
    @Override
    public void run() {
        // 获取请求数据信息
        System.out.println("接收数据开始处理!");
        BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
        PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);

        // 读取数据前6位，获取请求数据长度
        char[] bodyBytes = new char[6];
        in.read(bodyBytes);
        String dataLengthStr = new String(bodyBytes);

        // 获取请求数据信息
        Integer dataLength = Integer.parseInt(dataLengthStr);
        System.out.println("请求数据长度:" + dataLength);

        bodyBytes = new char[dataLength];
        in.read(bodyBytes);
        String requestBodyInfo = new String(bodyBytes);
        System.out.println("请求数据:" + requestBodyInfo);

        // 请求数据转换为Person对象
        Product product = JSON.parseObject(requestBodyInfo, Product.class);
        product.setId(IdUtil.simpleUUID());
        productMapper.insert(product);

        // 响应数据
        String rspJSONInfo = JSONObject.toJSONString(product);

        // 响应数据长度标识位 eg: 000667
        String prefixLength = SocketUtil.leftFixedZero(6, rspJSONInfo.length());

        // 最终响应数据
        String finalRspInfo = prefixLength.concat(rspJSONInfo);
        System.out.println("响应数据:" + finalRspInfo);
        out.println(finalRspInfo);
    }
}

socket工具类

package cn.git.socket;

/**
 * @description: socket工具类
 * @program: bank-credit-sy
 * @author: lixuchun
 * @create: 2023-03-20
 */
public class SocketUtil {

    /**
     * 左补0
     * eg: length = 6, num = 123, return 000123
     *
     * @param length 长度
     * @param num    数字
     * @return
     */
    public static String leftFixedZero(int length, int num) {
        return String.format("%0" + length + "d", num);
    }

}

3.测试

启动服务，观察socket监听端口 7777 是否正常启动监听,观察如下，socket服务端正常启动监听端口
在这里插入图片描述
开始模拟多客户端调用，请求 http://localhost:8088/socket/client 接口，循环异步发起 200 socket 请求。

观察后台信息

观察数据库，发现数据已经正确导入了，成功插入了 200 条数据信息