java的com口通讯，javacom口通讯,import gnu.i

java的com口通讯，javacom口通讯,import gnu.i

import gnu.io.CommPortIdentifier;  import gnu.io.PortInUseException;  import gnu.io.SerialPort;  import gnu.io.SerialPortEvent;  import gnu.io.SerialPortEventListener;  import gnu.io.UnsupportedCommOperationException;  import java.io.IOException;  import java.io.InputStream;  import java.util.Enumeration;  import java.util.TooManyListenersException;  public class SimpleRead implements Runnable, SerialPortEventListener {      static CommPortIdentifier portId;      static Enumeration portList;      InputStream inputStream;      SerialPort serialPort;      Thread readThread;      public static void main(String[] args) {          String com="4";          if(args!=null&amp;&amp;args.length>=1)          com=args[0];          portList = CommPortIdentifier.getPortIdentifiers();          // 检索系统串口          while (portList.hasMoreElements()) {              portId = (CommPortIdentifier) portList.nextElement();              /*如果端口类型是串口，则打印出其端口信息*/               if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {                  System.out.println("------------------------");                  System.out.println("系统可用串口: "+portId.getName());                  System.out.println("------------------------");                  // 指定COM口                  if (portId.getName().equals("COM"+com)) {                      System.out.println("找到COM"+com+"口,初始化...");                      SimpleRead reader = new SimpleRead();                  }else{                      System.out.println("无法找到COM"+com+"口,请重新指定...");                  }              }          }      }      public SimpleRead() {          try {          // 打开COM串口 2000 设置毫秒数 超时等待时间              serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);              System.out.println("COM口打开成功！");          } catch (PortInUseException e) {              System.out.println("端口被占用");          }          try {              inputStream = serialPort.getInputStream();              System.out.println("获得输入流...");          } catch (IOException e) {          }          //进行端口监听 , 当事件发生自动调用 serialEvent方法          try {              serialPort.addEventListener(this);          } catch (TooManyListenersException e) {          }          serialPort.notifyOnDataAvailable(true);          //设置通讯位          try {              System.out.println("设置通讯位...");              serialPort.setSerialPortParams(115200,// 设置波特率                      SerialPort.DATABITS_8,// 数据位数                      SerialPort.STOPBITS_1,// 停止位                      SerialPort.PARITY_NONE);// 奇偶位          } catch (UnsupportedCommOperationException e) {          }          // 启动线程，监听          readThread = new Thread(this);//线程负责每接收一次数据休眠20秒钟          readThread.start();      }      public void run() {          try {              System.out.println("监听...");              Thread.sleep(20000);//休息20秒          } catch (Exception e) {          }      }      // 处理侦听到的串口事件      public synchronized void serialEvent(SerialPortEvent event) {      //    System.out.println("接收数据...\r\n");          switch (event.getEventType()) {          case SerialPortEvent.BI://BI - 通讯中断.          case SerialPortEvent.OE://OE - 溢位错误.          case SerialPortEvent.FE://FE - 帧错误.          case SerialPortEvent.PE://PE - 奇偶校验错.          case SerialPortEvent.CD://CD - 载波检测.          case SerialPortEvent.CTS://CTS - 清除发送.          case SerialPortEvent.DSR://DSR - 数据设备准备好.          case SerialPortEvent.RI://RI - 　振铃指示.          case SerialPortEvent.OUTPUT_BUFFER_EMPTY://OUTPUT_BUFFER_EMPTY - 输出缓冲区已清空              break;          case SerialPortEvent.DATA_AVAILABLE://DATA_AVAILABLE - 有数据到达              byte[] readBuffer = new byte[10000];              try {                  //读数据                  while (inputStream.available() > 0) {                      int numBytes = inputStream.read(readBuffer);                  }                  String str=new String(readBuffer);                  if(str.equals("exit")){                      inputStream.close();serialPort.close();                  }                  //输出内容                  System.out.println("<------开始------->");                  System.out.println(str+"==============");                  System.out.println("<------结束------->");                  System.out.println("                    ");              } catch (IOException e) {              }              break;          }      }  }