Class HashingOutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

com.google.common.hash.HashingOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

@Beta
public final class HashingOutputStream
extends FilterOutputStream

An OutputStream that maintains a hash of the data written to it.

Since:

16.0

Author:

Zoe Piepmeier

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor	Description
HashingOutputStream(HashFunction hashFunction, OutputStream out)	Creates an output stream that hashes using the given HashFunction, and forwards all data written to it to the underlying OutputStream.

Method Summary

Modifier and Type	Method	Description
void	close()
HashCode	hash()	Returns the HashCode based on the data written to this stream.
void	write(byte[] bytes, int off, int len)
void	write(int b)

Methods inherited from class java.io.FilterOutputStream

flush, write

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

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

Constructor Details

HashingOutputStream

public HashingOutputStream(HashFunction hashFunction,
 OutputStream out)

Creates an output stream that hashes using the given HashFunction, and forwards all data written to it to the underlying OutputStream.

The OutputStream should not be written to before or after the hand-off.

Method Details

write

public void write(int b)
           throws IOException

Overrides:

write in class FilterOutputStream

Throws:

IOException

write

public void write(byte[] bytes,
 int off,
 int len)
           throws IOException

Overrides:

write in class FilterOutputStream

Throws:

IOException

hash

public HashCode hash()

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

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class FilterOutputStream

Throws:

IOException