RFIDtagRead.java

/* Sample java code to read an RFID tag */

import java.io.*;
import java.util.*;
import javax.comm.*;

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

    InputStream inputStream;
    SerialPort serialPort;
    Thread readThread;
    //Array consisting of SOH, length, command, data, BCC
    static byte[] bytearray = {0x01, 0x02, 0x09, 0x32, 0x39};
   
    static OutputStream outputStream;
    static int n =0;    
            
    public static void main(String[] args) {
		//Enumerate a list of available ports 
        portList = CommPortIdentifier.getPortIdentifiers();
		// Identify the ports. I connected the reader with COM1
        while (portList.hasMoreElements()) {
            portId = (CommPortIdentifier) portList.nextElement();
            if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
                if (portId.getName().equals("COM1")) {
					System.out.println("The port is: " + portId.getName());
                    RFIDTagRead reader = new RFIDTagRead();
                }
            }

        }
    }
    public RFIDTagRead() {
        try {
			//Open the COM1 port and name it MicroReader with timeout 2000ms
            serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);
        } catch (Exception e) {System.out.println("Port Error");}
		try {
            outputStream = serialPort.getOutputStream();
			// Write the stream of data conforming to PC to reader protocol
            outputStream.write(bytearray);
            outputStream.flush();
            
            System.out.println("The following bytes are being written");
            for(int i=0; i<bytearray.length; i++)
                System.out.println(bytearray[i]);
            System.out.println("Tag will be read when its in the field of the reader");
        } catch (IOException e) {}
    
		// Set Serial Port parameter
		try {
				serialPort.setSerialPortParams(9600,
					SerialPort.DATABITS_8,
					SerialPort.STOPBITS_1,
					SerialPort.PARITY_NONE);
		} catch (UnsupportedCommOperationException e) {}
		try {
			//Register an event listener object to the port
			serialPort.addEventListener(this);
		} catch (TooManyListenersException e){
			System.out.println("Too Many Listeners");
		} 
        
		//Specify an event type. On data availability, triggers serialEvent method
		serialPort.notifyOnDataAvailable(true);
        try {
			//Associate an InputStream object with this port.
            inputStream = serialPort.getInputStream();
        } catch (IOException e) {}
    
		//Start a thread to handle the time-to-read the tag
        readThread = new Thread(this);
        readThread.start(); 
    }
   
	public void run() {
		try {
				Thread.sleep(56);
			} catch (InterruptedException e) {} 
		} 
    
	//This method is called by notifyOnDataAvailabe()
    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:
		
				n++; //to count the number of readings
				System.out.println("The reading description of RFID Tag" + " " + n);
				
				//array size must not be less than the number of bytes to be read     
				byte[] readBuffer = new byte[20]; // to store the read data
			
				int numbyte = 0;
				try {
					while(inputStream.available() >0) {
					
						// Read the RFID data and store in the byte array
						numbyte = inputStream.read(readBuffer);
						System.out.println("Number of Bytes read: " + numbyte);
					}
				} catch (IOException e) {} 
				
				if( readBuffer[0] == 1) /*check if start bit is detected */
				{
					int length = readBuffer[1];
					// Identify the Transponder type
					switch(readBuffer[2]) {
						case 12 :
						{
							System.out.print("RFID is RO:" + "\t");
						break;
						}
						case 13 :
						{
							System.out.print("RFID is R/W:" + "\t");
						break;
						}
						case 14:
						{
							System.out.print("RFID is MPT/SAMPT:" + "\t");
						break;
						}
						case 15:
						{
							System.out.print("RFID is Other:" + "\t");
							break;
						}
					}
					
					// Write the actual tag reading in Hexadecimal  
					for( int m = length+1; m > 2; m--)
						System.out.print(Integer.toHexString(readBuffer[m] & 255));
				}
				System.out.println(" ");
				System.out.println("\t" + "Read Sucessful");
				System.out.println("----------------------------------");
				break;
		}
    }
}