本次分享的是一个简单的Web项目里使用的Socket通信案例

1、建立监听类：

package com.trust.fricem.TCPC.service;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.support.WebApplicationContextUtils;import javax.servlet.ServletContextEvent;import javax.servlet.ServletContextListener;/** * @Author:Singularity * @Date:2019/6/1 14:23 * @Description: Socket 服务监听 */public class SocketServiceLoader implements ServletContextListener {    //socket server 线程    private SocketThread socketThread;    /**     * 当Servlet 容器启动Web 应用时调用该方法。在调用完该方法之后，容器再对Filter 初始化，     * 并且对那些在Web 应用启动时就需要被初始化的Servlet 进行初始化。     */    @Override    public void contextInitialized(final ServletContextEvent sce) {        System.out.println("容器启动-------");        if (null == socketThread) {            //新建线程类            WebApplicationContext wac = WebApplicationContextUtils.getWebApplicationContext(sce.getServletContext());            socketThread = new SocketThread(null, wac);            //启动线程            socketThread.start();        }    }    /**     * 当Servlet 容器终止Web 应用时调用该方法。在调用该方法之前，容器会先销毁所有的Servlet 和Filter 过滤器。     */    @Override    public void contextDestroyed(ServletContextEvent sce) {        System.out.println("容器终止-------");        if (null != socketThread && !socketThread.isInterrupted()) {            socketThread.closeSocketServer();            socketThread.interrupt();        }    }}

2、创建线程类，同时创建 ServerSocket 服务端并监听客户端的连接

package com.trust.fricem.TCPC.service;import com.trust.fricem.TCPC.controller.SocketDataDealController;import org.springframework.web.context.WebApplicationContext;import java.io.*;import java.net.InetAddress;import java.net.ServerSocket;import java.net.Socket;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;/** * @Author:Singularity * @Date:2019/6/1 14:32 * @Description: Socket 服务端 */public class SocketThread extends Thread {    private ExecutorService threadPool = Executors.newFixedThreadPool(100);    private ServerSocket serverSocket = null;    private WebApplicationContext webApplicationContext = null;    Socket socket;    BufferedReader reader;    BufferedWriter writer;    public SocketThread(ServerSocket serverScoket, WebApplicationContext wac) {        try {            if (null == serverSocket) {                this.serverSocket = new ServerSocket(8088);                webApplicationContext = wac;                System.out.println("socket start");                System.out.println("Spring 容器 webApplicationContext 获取");            }        } catch (Exception e) {            System.out.println("SocketThread创建socket服务出错");            e.printStackTrace();        }    }    public void run() {        while (!this.isInterrupted()) {            try {                //1、创建一个服务器端Socket，即ServerSocket，指定绑定的端口，并监听此端口 1024-65535的某个端口                while (true) {
   // 巧用死循环                    //2、调用accept()方法开始监听，等待客户端的连接                    socket = serverSocket.accept();                    InetAddress address = socket.getInetAddress();//获取远程客户端的IP信息                    System.out.println("InetAddress:" + address);                    System.out.println("IP地址:" + address.getHostAddress());                    System.out.println("主机名:" + address.getHostName());                    reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));//读取客户端消息                    writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));//向客户端写消息                    try {                        //3、获取输入流，并读取客户端信息                        String info = null;                        SocketDataDealController sdd = new SocketDataDealController(webApplicationContext);                        while (!(info = reader.readLine()).equals("bye")) {                            System.out.println("收到来自客户端的发送的消息是：" + new String(info.getBytes(), "UTF-8"));                            String returnInfo = sdd.dealSocketData(info);                            System.out.println("给客户端的发送的消息是：" + returnInfo);                            writer.write(new String(returnInfo.getBytes(), "UTF-8") + "\n");                            writer.flush();                        }                    } catch (IOException e) {                        e.printStackTrace();                    } finally {                        try {                            if (reader != null) {                                reader.close();                            }                            if (writer != null) {                                writer.close();                            }                            if (socket != null) {                                System.out.println("Socket通道关闭");                                socket.close();                            }                        } catch (Exception e2) {                            e2.printStackTrace();                        }                    }                }            } catch (Exception e) {                e.printStackTrace();            }        }    }    public void closeSocketServer() {        try {            if (null != serverSocket && !serverSocket.isClosed()) {                System.out.println("ServerSocket 终止");                serverSocket.close();            }        } catch (IOException e) {            e.printStackTrace();        }    }}

3、处理客户端数据类，其中包含调用 Service 层方法的用法

package com.trust.fricem.QRCode.controller;import com.trust.fricem.QRCode.entity.ProdQRCodeEntity;import com.trust.fricem.QRCode.entity.ReturnMessage;import com.trust.fricem.QRCode.entity.UniversalcodeEntity;import com.trust.fricem.QRCode.service.ProdQRCodeService;import com.trust.fricem.QRCode.service.UniversaleCodeService;import com.trust.fricem.common.Constant;import com.trust.fricem.common.util.ASCIIUtils;import com.trust.fricem.common.util.CRC8;import com.trust.fricem.equipment.entity.EquipmenttypeEntity;import com.trust.fricem.equipment.service.EquipmenttypeDisService;import com.trust.fricem.product.entity.ProducttypeEntity;import com.trust.fricem.product.service.ProductTypeService;import org.springframework.web.context.WebApplicationContext;/** * GPRS 通信接口 * @author Singularity * @Time 2019.2.25 */public class SCMInterface {    private WebApplicationContext context = null;    private ProdQRCodeService prodQRCodeService;    private EquipmenttypeDisService equipmenttypeDisService;    private ProductTypeService productTypeService;    private UniversaleCodeService universaleCodeService;    public SCMInterface(WebApplicationContext webApplicationContext) {        context = webApplicationContext;        // 利用 webApplicationContext 创建 service         prodQRCodeService = context.getBean(ProdQRCodeService.class);        equipmenttypeDisService = context.getBean(EquipmenttypeDisService.class);        productTypeService = context.getBean(ProductTypeService.class);        universaleCodeService = context.getBean(UniversaleCodeService.class);    }    /**     * 接口1     */    public String receiveMessage(String param) {        ReturnMessage object = null;        String returnStr = null;        if (null != object) {            if (null != object.getCodeStr()) {                String str = object.getCodeStr();                if (null != str && "" != str) {                    //二维码类型标识                    String codeType = str.substring(0, 2);                    if (Constant.PROQrCode_BS.equals(codeType)) {
   //----普通二维码                        returnStr = prodQRCodeService.updateQrCodeInfo(object);//修改二维码加工状态                    }                    if (Constant.PROQrCode_WS.equals(codeType)) {
   //----万能二维码                        returnStr = universaleCodeService.saveUniversaleCode(object);//添加万能码使用记录数据                        //returnStr = CRC8.returnType(Constant.PROQrCode_SUCCESS, Constant.PROQrCode_EQUIPNO);                    }                }            }        }        return returnStr;    }}

4、再 Web.xml 中添加监听

         
             
      
       org.springframework.web.context.ContextLoaderListener
          
         
         
             
      
       org.springframework.web.util.IntrospectorCleanupListener
          
         
         
             
      
       com.trust.fricem.TCPC.service.SocketServiceLoader
          
     

注意：由于使用的是 Servlet 的监听方法，servlet 容器是在 Spring 容器之前加载的，而本次我用的是 SSM 框架，其中的 service 层和 dao 层等使用 Spring 容器管理的，所以上方的黄色标注的地方调用的方法会报错， 其中的 webApplicationContext 就是为了解决，这个问题 （有什么不对或者不合理的地方，欢迎大家赐教！）