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<JDK>\bin目录下;将comm.jar复制到<JDK>\lib;把 javax.comm.properties也同样拷贝到<JDK>\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; }
时间紧迫,到此为止,希望能够对初学者有些帮助,此文章同时在CSDN发布(http://blog.csdn.net/yweige2010/article/details/8053646).