public
class
DigestOutputStream
extends FilterOutputStream
java.lang.Object | |||
↳ | java.io.OutputStream | ||
↳ | java.io.FilterOutputStream | ||
↳ | java.security.DigestOutputStream |
A transparent stream that updates the associated message digest using the bits going through the stream.
To complete the message digest computation, call one of the
digest
methods on the associated message
digest after your calls to one of this digest ouput stream's
write
methods.
It is possible to turn this stream on or off (see
on
). When it is on, a call to one of the
write
methods results in
an update on the message digest. But when it is off, the message
digest is not updated. The default is for the stream to be on.
See also:
Fields | |
---|---|
protected
MessageDigest |
digest
The message digest associated with this stream. |
Inherited fields |
---|
From
class
java.io.FilterOutputStream
|
Public constructors | |
---|---|
DigestOutputStream(OutputStream stream, MessageDigest digest)
Creates a digest output stream, using the specified output stream and message digest. |
Public methods | |
---|---|
MessageDigest
|
getMessageDigest()
Returns the message digest associated with this stream. |
void
|
on(boolean on)
Turns the digest function on or off. |
void
|
setMessageDigest(MessageDigest digest)
Associates the specified message digest with this stream. |
String
|
toString()
Prints a string representation of this digest output stream and its associated message digest object. |
void
|
write(byte[] b, int off, int len)
Updates the message digest (if the digest function is on) using the specified subarray, and in any case writes the subarray to the output stream. |
void
|
write(int b)
Updates the message digest (if the digest function is on) using the specified byte, and in any case writes the byte to the output stream. |
Inherited methods | |
---|---|
From
class
java.io.FilterOutputStream
| |
From
class
java.io.OutputStream
| |
From
class
java.lang.Object
| |
From
interface
java.io.Closeable
| |
From
interface
java.io.Flushable
| |
From
interface
java.lang.AutoCloseable
|
DigestOutputStream (OutputStream stream, MessageDigest digest)
Creates a digest output stream, using the specified output stream and message digest.
Parameters | |
---|---|
stream |
OutputStream :
the output stream. |
digest |
MessageDigest :
the message digest to associate with this stream.
|
MessageDigest getMessageDigest ()
Returns the message digest associated with this stream.
Returns | |
---|---|
MessageDigest |
the message digest associated with this stream. |
void on (boolean on)
Turns the digest function on or off. The default is on. When
it is on, a call to one of the write
methods results in an
update on the message digest. But when it is off, the message
digest is not updated.
Parameters | |
---|---|
on |
boolean :
true to turn the digest function on, false to turn it
off.
|
void setMessageDigest (MessageDigest digest)
Associates the specified message digest with this stream.
Parameters | |
---|---|
digest |
MessageDigest :
the message digest to be associated with this stream. |
See also:
String toString ()
Prints a string representation of this digest output stream and its associated message digest object.
Returns | |
---|---|
String |
a string representation of the object. |
void write (byte[] b, int off, int len)
Updates the message digest (if the digest function is on) using
the specified subarray, and in any case writes the subarray to
the output stream. That is, if the digest function is on (see
on
), this method calls update
on the message digest associated with this stream, passing it
the subarray specifications. This method then writes the subarray
bytes to the output stream, blocking until the bytes are actually
written.
Parameters | |
---|---|
b |
byte :
the array containing the subarray to be used for updating
and writing to the output stream. |
off |
int :
the offset into b of the first byte to
be updated and written. |
len |
int :
the number of bytes of data to be updated and written
from b , starting at offset off . |
Throws | |
---|---|
IOException |
if an I/O error occurs. |
See also:
void write (int b)
Updates the message digest (if the digest function is on) using
the specified byte, and in any case writes the byte
to the output stream. That is, if the digest function is on
(see on
), this method calls
update
on the message digest associated with this
stream, passing it the byte b
. This method then
writes the byte to the output stream, blocking until the byte
is actually written.
Parameters | |
---|---|
b |
int :
the byte to be used for updating and writing to the
output stream. |
Throws | |
---|---|
IOException |
if an I/O error occurs. |
See also: