JAVA使用RXTXcomm进行唇口通信

1.引入RXTXcomm.JAR包

• 首先下载相应的jar文件
  压缩包包括:RXTXcomm.jar(64位环境)、win32com.dll和javax.comm.properties。
  下载地址:https://download.csdn.net/download/mr_yaoziyang/11939205
  介绍：RXTXcomm.jar提供了通讯用的java API，win32com.dll提供了供RXTXcomm.jar调用的本地驱动接口，javax.comm.properties是这个驱动的类配置文件

• 拷贝RXTXcomm.jar到jrelibext目录下面;

• 拷贝javax.comm.properties到jrelib目录下面;

• 拷贝win32com.dll到jrebin目录下面;

2.启动类

package com.datago.serialport;

import com.datago.serialport.controller.boot.MyLister;
import com.datago.serialport.controller.boot.PortInit;
import com.datago.serialport.controller.boot.SerialPortUtil;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

import javax.annotation.PreDestroy;

@SpringBootApplication
public class SerialPortApplication {

    public static void main(String[] args) {
        SpringApplication.run(SerialPortApplication.class, args);
    }


    @PreDestroy
    public void destory() {
        //关闭应用前，关闭端口
        SerialPortUtil serialPortUtil = SerialPortUtil.getSerialPortUtil();
        serialPortUtil.removeListener(PortInit.serialPort, new MyLister());
        serialPortUtil.closePort(PortInit.serialPort);
    }
}

3.启动程序打开串口通信，添加端口监听

package com.datago.serialport.controller.boot;

import gnu.io.SerialPort;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.stereotype.Component;

import java.util.ArrayList;


@Component
public class PortInit implements ApplicationRunner {

    public static SerialPort serialPort = null;

    @Value("${portname}")
    private String portname;

    @Override
    public void run(ApplicationArguments args) {
        //查看所有串口
        SerialPortUtil serialPortUtil = SerialPortUtil.getSerialPortUtil();
        ArrayList port = serialPortUtil.findPort();
        System.out.println("发现全部串口：" + port);
        System.out.println("打开指定portname：" + portname);
        //打开该对应portname名字的串口
        SerialPort serialPort = serialPortUtil.openPort(portname, 9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
        this.serialPort=serialPort;
        //给对应的serialPort添加监听器
        serialPortUtil.addListener(serialPort, new MyLister());
        System.out.println("可以正常发送数据");
    }
}

4.监听类

package com.datago.serialport.controller.boot;

import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
import lombok.SneakyThrows;

import java.util.Date;


public class MyLister implements SerialPortEventListener {



    @Override
    @SneakyThrows
    public void serialEvent(SerialPortEvent arg0) {
        if (arg0.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
            SerialPortUtil serialPortUtil = SerialPortUtil.getSerialPortUtil();
            SerialPort serialPort = PortInit.serialPort;
            byte[] bytes = serialPortUtil.readFromPort(serialPort);
            serialPortUtil.sendToPort(serialPort,"-----nihao-----".getBytes());
            String byteStr = new String(bytes, 0, bytes.length).trim();
            System.out.println("================start============");
            System.out.println(new Date() + "读到的字节数组：-----" + byteStr);
            String needData = printHexString(bytes);
            System.out.println(new Date()+"字节数组转字符串：------"+needData);
            String s = hexStringToString(needData).trim();
            if (s.equals("1")){
                //关闭应用前，关闭端口
                serialPortUtil.removeListener(serialPort, new MyLister());
                serialPortUtil.closePort(serialPort);
                System.out.println("==================close=====================");
            }
            System.out.println(new Date()+"16进制字符串转字符串：------"+hexStringToString(needData));
            System.out.println("================end=============");
        }
    }



    //字节数组转字符
    private String printHexString(byte[] b) {
        StringBuffer sdf = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            String hex = Integer.toHexString(b[i] & 0xFF);
            if (hex.length() == 1) {
                hex = "0" + hex;
            }
            sdf.append(hex.toUpperCase() + " ");
        }
        return sdf.toString().trim();
    }

    //16进制转换为String类行字符串
    public static String hexStringToString(String s) {
        if (s == null || s.equals("")) {
            return null;
        }
        s = s.replace(" ", "");
        byte[] baKeyword = new byte[s.length() / 2];
        for (int i = 0; i < baKeyword.length; i++) {
            try {
                baKeyword[i] = (byte) (0xff & Integer.parseInt(s.substring(i * 2, i * 2 + 2), 16));
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        try {
            s = new String(baKeyword, "UTF-8");
            new String();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return s;
    }


}

5.串口通信工具类

package com.datago.serialport.controller.boot;

import gnu.io.*;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.TooManyListenersException;


@Slf4j
public class SerialPortUtil {

    private static SerialPortUtil serialPortUtil = null;

    static {
        //在该类被ClassLoader加载时就初始化一个serialTool对象
        if (serialPortUtil == null) {
            serialPortUtil = new SerialPortUtil();
        }
    }

    //私有化SerialTool类的构造方法，不允许其他类生成SerialTool对象
    private SerialPortUtil() {
    }

    
    public static SerialPortUtil getSerialPortUtil() {
        if (serialPortUtil == null) {
            serialPortUtil = new SerialPortUtil();
        }
        return serialPortUtil;
    }

    
    public ArrayList findPort() {
        //获取当前所有可用串口
        Enumeration portList = CommPortIdentifier.getPortIdentifiers();

        ArrayList portNameList = new ArrayList<>();

        //将可用串口名添加到List并返回该List
        while (portList.hasMoreElements()) {
            String portName = portList.nextElement().getName();
            portNameList.add(portName);
        }

        return portNameList;
    }


    
    public SerialPort openPort(String portName, int baudrate, int databits, int parity, int stopbatis) {

        try {
            //通过端口名识别端口
            CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
            //打开端口，并给端口名字一个timeout（打开操作的超时时间）
            CommPort commPort = portIdentifier.open(portName, 2000);
            //判断是不是串口
            if (commPort instanceof SerialPort) {
                SerialPort serialPort = (SerialPort) commPort;
                //设置一下串口的波特率等参数
                try {
                    serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
                } catch (UnsupportedCommOperationException e) {
                    e.printStackTrace();
                }

                log.info("Open-------------{}" + portName + "sucessfully");
                return serialPort;
            } else {
                log.error("不是串口----------{}");
            }
        } catch (NoSuchPortException e) {
            log.error("没有找到端口--------------{}");
            e.printStackTrace();
        } catch (PortInUseException e) {
            log.error("端口被占用--------------{}");
            e.printStackTrace();
        }
        return null;
    }

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


    
    public void sendToPort(SerialPort serialPort, byte[] order) {
        OutputStream out = null;
        try {
            out = serialPort.getOutputStream();
            out.write(order);
            out.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (out != null) {
                    out.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    
    public byte[] readFromPort(SerialPort serialPort){
        InputStream in=null;
        byte[] bytes=null;
        try {
            in=serialPort.getInputStream();
            int bufflenth=in.available();
            while (bufflenth!=0){
                bytes=new byte[bufflenth];
                in.read(bytes);
                bufflenth=in.available();
            }
        }catch (IOException e){
            e.printStackTrace();
        }finally {
            try {
                in.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return  bytes;
    }

    
    public void addListener(SerialPort port,SerialPortEventListener listener){
        try {
            //给串口添加监听器
            port.addEventListener(listener);
            //设置当有数据到时唤醒监听接收线程
            port.notifyOnDataAvailable(true);
            //设置当通信中断时唤醒中断线程
            port.notifyOnBreakInterrupt(true);

        }catch (TooManyListenersException e){
            log.error("太多监听器-------------{}");
            e.printStackTrace();
        }
    }

    
    public void removeListener(SerialPort port,SerialPortEventListener listener){
        //删除串口监听器
        port.removeEventListener();
    }
}