0

这是我读取串行输入的程序，一切正常。编译成功，但是当我尝试执行下面的代码时，它会显示一个错误，我附在下面的图像。

import java.io.*;
import java.util.*;
import gnu.io.*;
import java.sql.*;


public class SimpleRead implements Runnable, SerialPortEventListener {
static CommPortIdentifier portId;
static Enumeration portList;
static Connection con=null;
static String url = "jdbc:mysql://localhost:3306/track";
static String uid="root";
static String pwd="root";

InputStream inputStream;
SerialPort serialPort;
Thread readThread;

public static void main(String[] args) {
    portList = CommPortIdentifier.getPortIdentifiers();

    while (portList.hasMoreElements()) {
        portId = (CommPortIdentifier) portList.nextElement();
        if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
             if (portId.getName().equals("COM1")) {
        //                if (portId.getName().equals("/dev/term/a")) {
                SimpleRead reader = new SimpleRead();
                    try
                    {

                        Class.forName("com.mysql.jdbc.Driver");
                        con = DriverManager.getConnection(url,uid,pwd);
                    }
                    catch(Exception s){
                        System.out.println(s);
                        }

        }
    }
}
}
public SimpleRead() {
    try {
        serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);
    } catch (PortInUseException e) {System.out.println(e);}
    try {
        inputStream = serialPort.getInputStream();
    } catch (IOException e) {System.out.println(e);}
try {
        serialPort.addEventListener(this);
} catch (TooManyListenersException e) {System.out.println(e);}
    serialPort.notifyOnDataAvailable(true);
    try {
        serialPort.setSerialPortParams(9600,
            SerialPort.DATABITS_8,
            SerialPort.STOPBITS_1,
            SerialPort.PARITY_NONE);
    } catch (UnsupportedCommOperationException e) {System.out.println(e);}
    readThread = new Thread(this);
    readThread.start();
}

public void run() {
    try {
        Thread.sleep(20000);
    } catch (InterruptedException e) {System.out.println(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:
        byte[] readBuffer = new byte[8];

        try {
                while (inputStream.available() > 0) {
                int numBytes = inputStream.read(readBuffer);
            }
            System.out.print(new String(readBuffer));
            } catch (IOException e) {System.out.println(e);}

        Statement st=null;
        try{
            st=con.createStatement();

           }
        catch(Exception ex){
            System.out.println(ex);
        }

        try{
            String idd = new String(readBuffer);

            if(idd.equals("05447646")||idd.equals("05447647")||idd.equals("05447649")||idd.equals("05447650")){

            String query = "INSERT INTO tablename1 (id) VALUES(?)";
            PreparedStatement pstm = con.prepareStatement(query);
            pstm.setString(1, idd);
            pstm.executeUpdate();
            pstm.close();}
            //st.executeUpdate("insert into asset(id) VALUES('"+idd+"'");
            //con.close();
            }
        catch(Exception ex){
            System.out.println(ex);
                    }

        }

}}

错误图像：

错误

请帮忙

4

1 回答 1

0

步骤 1. 打开命令提示符并输入

java版本
这将向您显示系统上安装 java 的位置。如果它不存在，那么您需要安装 java

第 2 步。打开 JCreator（您的 java IDE），然后将正确的路径设置为您的 java 目录。

步骤 3. 在控制面板->系统->高级设置->环境变量下打开环境变量。并设置/添加一个类路径
JAVA_DIRECTORY/bin

第 4 步在您的 JAVA_DIRECTORY/jre/lib/ext 文件夹中复制所有 .jar 文件，例如 RXTX 和 JConnector 等。

步骤 5. 请关闭计算机，然后重新打开

于 2013-06-10T08:19:20.293 回答