Package java.security

Class DigestOutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

java.security.DigestOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class DigestOutputStream
extends FilterOutputStream

DigestOutputStream is a FilterOutputStream which maintains an associated message digest.

Field Summary

Fields

Modifier and Type	Field	Description
protected MessageDigest	digest	The message digest for this stream.

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor	Description
DigestOutputStream(OutputStream stream, MessageDigest digest)	Constructs a new instance of this DigestOutputStream, using the given stream and the digest.

Method Summary

Modifier and Type	Method	Description
MessageDigest	getMessageDigest()	Returns the message digest for this stream.
void	on(boolean on)	Enables or disables the digest function (default is on).
void	setMessageDigest(MessageDigest digest)	Sets the message digest which this stream will use.
String	toString()	Returns a string containing a concise, human-readable description of this DigestOutputStream including the digest.
void	write(byte[] b, int off, int len)	Writes len bytes into the stream, starting from the specified offset.
void	write(int b)	Writes the specified int to the stream.

Methods inherited from class java.io.FilterOutputStream

close, flush

Methods inherited from class java.io.OutputStream

write

Methods inherited from class java.lang.Object

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

Field Detail

digest

protected MessageDigest digest

The message digest for this stream.

Constructor Detail

DigestOutputStream

public DigestOutputStream(OutputStream stream,
                          MessageDigest digest)

Constructs a new instance of this DigestOutputStream, using the given stream and the digest.

Parameters:

stream - the output stream.

digest - the message digest.

Method Detail

getMessageDigest

public MessageDigest getMessageDigest()

Returns the message digest for this stream.

Returns:

the message digest for this stream.

setMessageDigest

public void setMessageDigest(MessageDigest digest)

Sets the message digest which this stream will use.

Parameters:

digest - the message digest which this stream will use.

write

public void write(int b)
           throws IOException

Writes the specified int to the stream. Updates the digest if this function is on(boolean).

Overrides:

write in class FilterOutputStream

Parameters:

b - the byte to be written.

Throws:

IOException - if writing to the stream causes a IOException

write

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

Writes len bytes into the stream, starting from the specified offset. Updates the digest if this function is on(boolean).

Overrides:

write in class FilterOutputStream

Parameters:

b - the buffer to write to.

off - the index of the first byte in b to write.

len - the number of bytes in b to write.

Throws:

IOException - if writing to the stream causes an IOException.

on

public void on(boolean on)

Enables or disables the digest function (default is on).

Parameters:

on - true if the digest should be computed, false otherwise.

See Also:

MessageDigest

toString

public String toString()

Returns a string containing a concise, human-readable description of this DigestOutputStream including the digest.

Overrides:

toString in class Object

Returns:

a printable representation for this DigestOutputStream.