java 实现串口通信
最近做了一个与硬件相关的项目,刚开始听说用java和硬件打交道,着实下了一大跳。java也可以操作硬件?
后来接触到是用java通过串口通信控制硬件感觉使用起来还不错,也很方便。
特拿出来和大家一起分享一下。
准备工作:
首先到SUN官网下载一个zip包:javacomm20-win32.zip
其中重要的有这几个文件:
win32com.dll
comm.jar
javax.comm.properties
按照说明配置好环境,如下:
将win32com.dll复制到\bin目录下;将comm.jar复制到\lib;把 javax.comm.properties也同样拷贝到\lib目录下。然而在真正运行使用串口包的时候,仅作这些是不够的。因 为通常当运行“java MyApp”的时候,是由JRE下的虚拟机启动MyApp的。而我们只复制上述文件到JDK相应目录下,所以应用程序将会提示找不到串口。解决这个问题的 方法很简单,我们只须将上面提到的文件放到JRE相应的目录下就可以了
到这一个可以java 串口开发环境就搭建完成了
确认本机可以使用的串口:
package test;
import java.util.Enumeration;
import java.util.HashMap;
import javax.comm.CommPortIdentifier;
import javax.comm.SerialPort;
     public class GetSerialPorts {
     
    
     public void listPortChoices() {
     
    
CommPortIdentifier portId;
Enumeration en = CommPortIdentifier.getPortIdentifiers();
// iterate through the ports.
     while (en.hasMoreElements()) {
     
    
portId = (CommPortIdentifier) en.nextElement();
     if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
     
    
System.out.println(portId.getName());
}
}
}
     public static void main(String[] args) {
     
    
GetSerialPorts GSP = new GetSerialPorts();
GSP.listPortChoices();
}
}
打开串口,关闭串口:
package test;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.HashMap;
import javax.comm.CommPortIdentifier;
import javax.comm.PortInUseException;
import javax.comm.SerialPort;
import javax.comm.UnsupportedCommOperationException;
     public class GetSerialPorts {
     
    
private CommPortIdentifier portId;
private SerialPort testPort;
private CommPortIdentifier myPort;
private InputStream is;
private OutputStream os;
     public void listPortChoices() {
     
    
Enumeration en = CommPortIdentifier.getPortIdentifiers();
// iterate through the ports.
     while (en.hasMoreElements()) {
     
    
portId = (CommPortIdentifier) en.nextElement();
     if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
     
    
System.out.println(portId.getName());
}
myPort = portId;// 任意取一个串口,比如com1
}
}
     public boolean openPort() {
     
    
     try {
     
    
testPort = (SerialPort) myPort.open(“COM1”, 500);// 注意这里必须换成一个真实的串口
     try {
     
    
this.testPort.setSerialPortParams(38400, SerialPort.DATABITS_8,
SerialPort.STOPBITS_1, SerialPort.PARITY_EVEN);
     } catch (UnsupportedCommOperationException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
}
     try {
     
    
this.testPort.enableReceiveTimeout(30);
     } catch (UnsupportedCommOperationException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
}
this.testPort.setOutputBufferSize(1024);
this.testPort.setInputBufferSize(1024);
     try {
     
    
this.is = this.testPort.getInputStream();
     } catch (IOException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
}
     try {
     
    
this.os = this.testPort.getOutputStream();
     } catch (IOException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
}
this.testPort.notifyOnDataAvailable(true);
this.testPort.notifyOnOutputEmpty(true);
this.testPort.notifyOnBreakInterrupt(true);
// this.printerPort.addEventListener(new PrintPortListener(is));
System.out.println(“打开com1机串口成功”);
return true;
     } catch (PortInUseException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
return false;
}
}
/**
* TODO 关闭端口
*
* @param
* @return Map
* @throws
*/
     public boolean closePort() {
     
    
// TODO Auto-generated method stub
     try {
     
    
     if (null != this.testPort) {
     
    
is.close();
os.close();
this.testPort.close();
}
System.out.println(“关闭COM1串口成功”);
return true;
     } catch (Exception e) {
     
    
// TODO Auto-generated catch block
// e.printStackTrace();
System.out.println(“关闭COM1串口失败”);
return false;
}
}
     public static void main(String[] args) {
     
    
GetSerialPorts GSP = new GetSerialPorts();
GSP.listPortChoices();
GSP.openPort();
}
}
读数据:
/**
* TODO 接收端口數據
*
* @param InputStream
* @return String
* @throws
*/
     public String readData(InputStream is) {
     
    
// 读取缓冲区域
byte[] readBuffer = new byte[4096];
int readDataLength = 0;
     try {
     
    
readDataLength = is.read(readBuffer);
     // for (byte b : readBuffer) {
     
    
// System.out.print(b);
// }
// System.out.println();
     } catch (IOException e) {
     
    
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
// 将真实数据保存到零时数组中
byte[] readTemp = new byte[readDataLength];
     for (int i = 0; i < readDataLength; i++) {
     
    
readTemp[i] = readBuffer[i];
}
// 将byte数组转换为16进制字符串
String stringTemp = FeelTheBase.bytesToHexString(readTemp);
// System.out.println(“指令返回值” + stringTemp);
return stringTemp;
}
感谢阅读,希望能帮助到大家,谢谢大家对本站的支持!
 
