CRC32

public class CRC32 extends Object
implements Checksum

A class that can be used to compute the CRC-32 of a data stream.

Passing a null argument to a method in this class will cause a NullPointerException to be thrown.

See Also

Public Constructor Summary

CRC32()
Creates a new CRC32 object.

Public Method Summary

long
getValue()
Returns CRC-32 value.
void
reset()
Resets CRC-32 to initial value.
void
update(byte[] b)
Updates the CRC-32 checksum with the specified array of bytes.
void
update(ByteBuffer buffer)
Updates the checksum with the bytes from the specified buffer.
void
update(byte[] b, int off, int len)
Updates the CRC-32 checksum with the specified array of bytes.
void
update(int b)
Updates the CRC-32 checksum with the specified byte (the low eight bits of the argument b).

Inherited Method Summary

Public Constructors

public CRC32 ()

Creates a new CRC32 object.

Public Methods

public long getValue ()

Returns CRC-32 value.

Returns
  • the current checksum value

public void reset ()

Resets CRC-32 to initial value.

public void update (byte[] b)

Updates the CRC-32 checksum with the specified array of bytes.

Parameters
b the array of bytes to update the checksum with

public void update (ByteBuffer buffer)

Updates the checksum with the bytes from the specified buffer. The checksum is updated using buffer.remaining() bytes starting at buffer.position() Upon return, the buffer's position will be updated to its limit; its limit will not have been changed.

Parameters
buffer the ByteBuffer to update the checksum with

public void update (byte[] b, int off, int len)

Updates the CRC-32 checksum with the specified array of bytes.

Parameters
b the byte array to update the checksum with
off the start offset of the data
len the number of bytes to use for the update
Throws
ArrayIndexOutOfBoundsException if off is negative, or len is negative, or off+len is greater than the length of the array b

public void update (int b)

Updates the CRC-32 checksum with the specified byte (the low eight bits of the argument b).

Parameters
b the byte to update the checksum with