deviceudpservice.java

用java写编写的一个GPS源代码请大家多多指教

package com.gps.center.dataservice;

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.w3c.dom.Document;
import java.io.File;
import org.w3c.dom.NodeList;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
import java.io.IOException;
import com.gps.center.baseclass.MsgObj;
import com.gps.center.baseclass.ParseData;

public class DeviceUdpService extends ParseData implements Runnable {
    private int DevicePort = 0;
    private String DeviceIP = "localhost";
    public DatagramSocket udpServer;

    public DeviceUdpService() {
        readxml();
        initializeOperations();
    }

    public void run() {
        try {
            while (super.openservice) {
                byte[] buf = new byte[1024];
                DatagramPacket dp = new DatagramPacket(buf, buf.length); //创建一个DatagramPacket接收数据
                udpServer.receive(dp);//接收
                String rcvd = dp.toString().trim();
                if (rcvd.length() > 1) {
                    MsgObj msg = new MsgObj();
                    //cMsgtype:1--TCPMSG,2--DEVICEUDPMSG,3--SMSMSG
                    //4--TCPSENDTODEVICE,5--UDPSENDTODEVICE,6--SMSSENDTODEVICE,7--TCPSENDTOTERMINAL,8--TCPRETURNTERMINAL
                    msg.cMsgType = DEVICEUDPMSG;
                    msg.cMsg = rcvd;
                    msg.cDeviceAdd = dp.getAddress();
                    msg.cUdpPort = dp.getPort();
                    msg.cUdpSocket = udpServer;
                    super.addRecieveMsg(msg);//添加到接收队列
                }
            }
        } catch (IOException e) {
            System.err.println("Communication error!");
            e.printStackTrace();
        }
    }

    public void initializeOperations() {//初始化UDP-Socket
        InetAddress ia = null;
        try {
            ia = InetAddress.getByName(DeviceIP); //
        } catch (UnknownHostException ex) {
            ex.printStackTrace();
            System.exit( -1);
        }
        try {
            udpServer = new DatagramSocket(DevicePort, ia);
        } catch (SocketException ex1) {
            udpServer.close();
            ex1.printStackTrace();
            System.exit( -1);
        }
    }

    private void readxml() {
        String strport;
        try {
            File f = new File("CenterInfo.xml");
            if (f.exists()) {
                DocumentBuilderFactory factory = DocumentBuilderFactory.
                                                 newInstance();
                DocumentBuilder builder = factory.newDocumentBuilder();
                Document doc = builder.parse(f);
                NodeList nl = doc.getElementsByTagName("Center");
                for (int i = 0; i < nl.getLength(); i++) {
                    strport = (doc.getElementsByTagName("CenterPort").item(i).
                               getFirstChild().
                               getNodeValue()).trim();
                    DeviceIP = (doc.getElementsByTagName("CenterIP").item(i).
                                getFirstChild().
                                getNodeValue()).trim();
                    try {
                        if (strport.length() > 0) {
                            DevicePort = Integer.parseInt(strport);
                        } else {
                            System.out.println("centerPort err");
                            System.exit( -1);
                        }

                    } catch (Exception e) {
                        System.out.println("centerPort and MaxDevice err");
                    }
                }
            } else {
                System.out.println("no find file：CenterInfo.xml");
                System.exit( -1);
            }

        } catch (Exception e) {
            e.printStackTrace();
            System.exit( -1);
        }
    }
}