Package com.google.common.hash

Class HashingInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

com.google.common.hash.HashingInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

@Beta
public final class HashingInputStream
extends java.io.FilterInputStream

An InputStream that maintains a hash of the data read from it.

Since:

16.0

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor	Description
HashingInputStream(HashFunction hashFunction, java.io.InputStream in)	Creates an input stream that hashes using the given HashFunction and delegates all data read from it to the underlying InputStream.

Method Summary

Modifier and Type	Method	Description
HashCode	hash()	Returns the HashCode based on the data read from this stream.
void	mark(int readlimit)	mark() is not supported for HashingInputStream
boolean	markSupported()	mark() is not supported for HashingInputStream
int	read()	Reads the next byte of data from the underlying input stream and updates the hasher with the byte read.
int	read(byte[] bytes, int off, int len)	Reads the specified bytes of data from the underlying input stream and updates the hasher with the bytes read.
void	reset()	reset() is not supported for HashingInputStream.

Methods inherited from class java.io.FilterInputStream

available, close, read, skip

Methods inherited from class java.io.InputStream

readAllBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

HashingInputStream

public HashingInputStream(HashFunction hashFunction,
                          java.io.InputStream in)

Creates an input stream that hashes using the given HashFunction and delegates all data read from it to the underlying InputStream.

The InputStream should not be read from before or after the hand-off.

Method Detail

read

public int read()
         throws java.io.IOException

Reads the next byte of data from the underlying input stream and updates the hasher with the byte read.

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

read

public int read(byte[] bytes,
                int off,
                int len)
         throws java.io.IOException

Reads the specified bytes of data from the underlying input stream and updates the hasher with the bytes read.

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

markSupported

public boolean markSupported()

mark() is not supported for HashingInputStream

Overrides:

markSupported in class java.io.FilterInputStream

Returns:

false always

mark

public void mark(int readlimit)

mark() is not supported for HashingInputStream

Overrides:

mark in class java.io.FilterInputStream

reset

public void reset()
           throws java.io.IOException

reset() is not supported for HashingInputStream.

Overrides:

reset in class java.io.FilterInputStream

Throws:

java.io.IOException - this operation is not supported

hash

public HashCode hash()

Returns the HashCode based on the data read from this stream. The result is unspecified if this method is called more than once on the same instance.