java 串口编程

通过JAVA与串口(RS232)通信实例

文章分类:Java编程 关键字: java com 串口 rs232

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();
        }
      }


}

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();
    }

}

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();
	}

}