Java compact1, compact2, compact3 java.security Class DigestOutputStream（JDK8）

Field Detail

• digest

  protected MessageDigest digest

  The message digest associated with this stream.

Constructor Detail

• DigestOutputStream

  public DigestOutputStream(OutputStream stream,
                            MessageDigest digest)

  Creates a digest output stream, using the specified output stream and message digest.

  Parameters:

  stream - the output stream.

  digest - the message digest to associate with this stream.

Method Detail

• getMessageDigest

  public MessageDigest getMessageDigest()

  Returns the message digest associated with this stream.

  Returns:

  the message digest associated with this stream.

  See Also:

  setMessageDigest(java.security.MessageDigest)

• setMessageDigest

  public void setMessageDigest(MessageDigest digest)

  Associates the specified message digest with this stream.

  Parameters:

  digest - the message digest to be associated with this stream.

  See Also:

  getMessageDigest()

• write

  public void write(int b)
             throws IOException

  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.

  Overrides:

  write in class FilterOutputStream

  Parameters:

  b - the byte to be used for updating and writing to the output stream.

  Throws:

  IOException - if an I/O error occurs.

  See Also:

  MessageDigest.update(byte)

• write

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

  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.

  Overrides:

  write in class FilterOutputStream

  Parameters:

  b - the array containing the subarray to be used for updating and writing to the output stream.

  off - the offset into b of the first byte to be updated and written.

  len - 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:

  MessageDigest.update(byte[], int, int)

• on

  public 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 - true to turn the digest function on, false to turn it off.

• toString

  public String toString()

  Prints a string representation of this digest output stream and its associated message digest object.

  Overrides:

  toString in class Object

  Returns:

  a string representation of the object.