import java.util.zip.CRC32;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

class CrcCheckSum {
	public static void main(String[] args) {
		try {
			FileInputStream inputStream = new FileInputStream("testfile.txt");
			CRC32 crcChecksum = new CRC32();
			long initialValue = crcChecksum.getValue();
			System.out.println("Initial value of CRC32 checkSum :"
					+ initialValue);
			byte[] b = new byte[128];
			while (inputStream.read(b) >= 0) {
			}
			crcChecksum.update(b, 0, b.length);
			long update = crcChecksum.getValue();
			System.out.println("After updating the value of  check sum : "
					+ update);
			crcChecksum.reset();
			long resetValue = crcChecksum.getValue();
			System.out.println("value of CRC32 CheckSum After reset :"
					+ resetValue);
		} catch (IOException e) {
			System.out.println("IOException : " + e);
		}
	}
}