This class implements the Checksum interface and computes a checksum on a stream of data using the CRC-32 algorithm. The CheckedInputStream and CheckedOutputStream classes provide a higher-level interface to computing checksums on streams of data.
public class CRC32 extends Object implements Checksum {
    // Default Constructor: public CRC32()
    // Public Instance Methods
            public long getValue();  // From Checksum
            public void reset();  // From Checksum
            public void update(int b);  // From Checksum
            public native void update(byte[] b, int off, int len);  // From Checksum
            public void update(byte[] b);
}
GZIPInputStream.crc, GZIPOutputStream.crc