oracle.security.crypto.core
Class DigestInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
oracle.security.crypto.core.DigestInputStream

public class DigestInputStream

extends java.io.FilterInputStream

An input stream that keeps a message digest of the bytes going through it.

The method computeCurrent() computes and returns the current digest.

Field Summary

protected MessageDigest

messageDigest The message digest used by this stream.

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

DigestInputStream(java.io.InputStream is, MessageDigest md)
Create a new DigestInputStream with specified InputStream and Message Digest.

Method Summary

byte[]	computeCurrent() Compute and return the current digest.
MessageDigest	getMessageDigest() Return the message digest for this stream.
int	read() Read one byte of data.
int	read(byte[] b, int off, int len) Reads into an array of bytes.
void	setMessageDigest(MessageDigest md) Set the message digest for this stream.

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

messageDigest

protected MessageDigest messageDigest

The message digest used by this stream.

Constructor Detail

DigestInputStream

public DigestInputStream(java.io.InputStream is,
                         MessageDigest md)

Create a new DigestInputStream with specified InputStream and Message Digest.

Method Detail

read

public int read()
         throws java.io.IOException

Read one byte of data. Blocks if no data is available. The message digest is updated.

Returns:

the byte read, or -1 if end of stream reached.

Throws:

java.io.IOException

read

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

Reads into an array of bytes. Blocks if no data is available. Updates the message digest.

Parameters:

b - the buffer which the data is read into

off - start offset of data

len - maximum number of bytes read

Returns:

the number of bytes read, or -1 if end of stream reached.

Throws:

java.io.IOException

computeCurrent

public byte[] computeCurrent()

Compute and return the current digest.

getMessageDigest

public MessageDigest getMessageDigest()

Return the message digest for this stream.

setMessageDigest

public void setMessageDigest(MessageDigest md)

Set the message digest for this stream.