通过JAVA与串口(RS232)通信实例

通过JAVA与串口(RS232)通信实例

博客分类： 
• J2SE

Java VB thread 

最近了解到的需求是需要需激光打刻机进行（RS232）串口通信， 
这里使用的是RXTX开源包实现的。 
之前并没有用java做过串口通信，而且这方面资料不是很多。 
项目实际应用中可能会采用VB开发（这个我就不会了） 

只不过用java尝试一下，记个笔记，希望可以对相关开发用些帮助。 

下面是实现代码 

 package test;

 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.util.Date;
 import java.util.Enumeration;
 import java.util.TooManyListenersException;

 import gnu.io.CommPortIdentifier;
 import gnu.io.PortInUseException;
 import gnu.io.SerialPort;
 import gnu.io.SerialPortEvent;
 import gnu.io.SerialPortEventListener;
 import gnu.io.UnsupportedCommOperationException;

 public class CommUtil implements SerialPortEventListener {

     InputStream inputStream; // 从串口来的输入流
     OutputStream outputStream;// 向串口输出的流
     SerialPort serialPort; // 串口的引用
     CommPortIdentifier portId;

     public CommUtil(Enumeration portList, String name) {
         while (portList.hasMoreElements()) {
             CommPortIdentifier temp = (CommPortIdentifier) portList.nextElement();
             if (temp.getPortType() == CommPortIdentifier.PORT_SERIAL) {// 判断如果端口类型是串口
                 if (temp.getName().equals(name)) { // 判断如果端口已经启动就连接
                     portId = temp;
                 }
             }
         }
         try {
             serialPort = (SerialPort) portId.open("My"+name, 2000);
         } catch (PortInUseException e) {

         }
         try {
             inputStream = serialPort.getInputStream();
             outputStream = serialPort.getOutputStream();
         } catch (IOException e) {
         }
         try {
             serialPort.addEventListener(this); // 给当前串口天加一个监听器
         } catch (TooManyListenersException e) {
         }
         serialPort.notifyOnDataAvailable(true); // 当有数据时通知
         try {
             serialPort.setSerialPortParams(2400, SerialPort.DATABITS_8, // 设置串口读写参数
                     SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
         } catch (UnsupportedCommOperationException e) {
         }
     }

     public void serialEvent(SerialPortEvent event) {
         switch (event.getEventType()) {
         case SerialPortEvent.BI:
         case SerialPortEvent.OE:
         case SerialPortEvent.FE:
         case SerialPortEvent.PE:
         case SerialPortEvent.CD:
         case SerialPortEvent.CTS:
         case SerialPortEvent.DSR:
         case SerialPortEvent.RI:
         case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
             break;

         case SerialPortEvent.DATA_AVAILABLE:// 当有可用数据时读取数据,并且给串口返回数据
             byte[] readBuffer = new byte[20];

             try {
                 while (inputStream.available() > 0) {
                     System.out.println(inputStream.available());
                     int numBytes = inputStream.read(readBuffer);
                     System.out.println(numBytes);
                 }
                 System.out.println(new String(readBuffer).trim());
             } catch (IOException e) {
                 e.printStackTrace();
             }
             break;
         }
     }
     public void send(String content){
         try {
             outputStream.write(content.getBytes());
         } catch (IOException e) {
             e.printStackTrace();
         }
     }

     public void ClosePort() {
         if (serialPort != null) {
           serialPort.close();
         }
       }


 }

测试 

 package test;

 import gnu.io.CommPortIdentifier;

 import java.util.Enumeration;

 public class Test {

     public static void main(String[] args) throws InterruptedException {
         Enumeration portList = CommPortIdentifier.getPortIdentifiers(); //得到当前连接上的端口

         CommUtil comm3 = new CommUtil(portList,"COM3");
         int i = 0;
         while(i<5)
         {
             Thread.sleep(3000);
             comm3.send("hello");
             i++;
         }
         comm3.ClosePort();
     }

 }

• rxtx-2.1-7-bins-r2.zip (596 KB)