程序包 java.util.zip

类 CRC32

java.lang.Object

java.util.zip.CRC32

所有已实现的接口:

Checksum

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.

另请参阅:

Checksum

构造器概要

构造器

构造器	说明
CRC32()	Creates a new CRC32 object.

方法概要

限定符和类型	方法	说明
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(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).
void	update(ByteBuffer buffer)	Updates the checksum with the bytes from the specified buffer.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

CRC32

public CRC32()

Creates a new CRC32 object.

方法详细资料

update

public void update(int b)

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

指定者:

update 在接口中 Checksum

参数:

b - the byte to update the checksum with

update

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

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

指定者:

update 在接口中 Checksum

参数:

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

抛出:

ArrayIndexOutOfBoundsException - if off is negative, or len is negative, or off+len is greater than the length of the array b

update

public void update(byte[] b)

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

参数:

b - the array of bytes to update the checksum with

update

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.

参数:

buffer - the ByteBuffer to update the checksum with

从以下版本开始:

1.8

reset

public void reset()

Resets CRC-32 to initial value.

指定者:

reset 在接口中 Checksum

getValue

public long getValue()

Returns CRC-32 value.

指定者:

getValue 在接口中 Checksum

返回:

the current checksum value