JAVA中基于RFID的读写

Question

我必须制作一个基于 RFID 的考勤系统，一旦从标签读取并找出它是哪个学生，我必须写入数据库。我的问题是我如何从 RFID 标签获取输入。JAVA 的输入缓冲区类是否提供足够的输入和输出还是我必须采取不同的方法。

Answer 1

为此，您可以使用 Java Communications API。我正在做同样的事情，java comm api 和 rxtx 对此工作得非常好。我有一个为此编写的程序。干得好：

import java.io.*;

import java.util.*;

import javax.comm.*;

public class SimpleRead implements Runnable, SerialPortEventListener {
    static CommPortIdentifier portId;
    static Enumeration portList;

    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("COM13")) {
            //                if (portId.getName().equals("/dev/term/a")) {
                    SimpleRead reader = new SimpleRead();
                 }
            }
        }
    }

    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[20];

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