- java.lang.Object
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- java.io.OutputStream
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- java.io.FilterOutputStream
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- java.security.DigestOutputStream
 
 
 
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- All Implemented Interfaces:
- Closeable,- Flushable,- AutoCloseable
 
 public class DigestOutputStream extends FilterOutputStream 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 digestmethods on the associated message digest after your calls to one of this digest output stream'swritemethods.It is possible to turn this stream on or off (see on). When it is on, a call to one of thewritemethods 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.- Since:
- 1.2
- See Also:
- MessageDigest,- DigestInputStream
 
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Field SummaryFields Modifier and Type Field Description protected MessageDigestdigestThe message digest associated with this stream.- 
Fields declared in class java.io.FilterOutputStreamout
 
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Constructor SummaryConstructors Constructor Description DigestOutputStream(OutputStream stream, MessageDigest digest)Creates a digest output stream, using the specified output stream and message digest.
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Method SummaryAll Methods Instance Methods Concrete Methods Modifier and Type Method Description MessageDigestgetMessageDigest()Returns the message digest associated with this stream.voidon(boolean on)Turns the digest function on or off.voidsetMessageDigest(MessageDigest digest)Associates the specified message digest with this stream.StringtoString()Prints a string representation of this digest output stream and its associated message digest object.voidwrite(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.voidwrite(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.- 
Methods declared in class java.io.FilterOutputStreamclose, flush, write
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Methods declared in class java.io.OutputStreamnullOutputStream
 
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Field Detail- 
digestprotected MessageDigest digest The message digest associated with this stream.
 
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Constructor Detail- 
DigestOutputStreampublic 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.
 
 
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Method Detail- 
getMessageDigestpublic MessageDigest getMessageDigest() Returns the message digest associated with this stream.- Returns:
- the message digest associated with this stream.
- See Also:
- setMessageDigest(java.security.MessageDigest)
 
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setMessageDigestpublic 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()
 
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writepublic void write(int b) throws IOExceptionUpdates 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 (seeon), this method callsupdateon the message digest associated with this stream, passing it the byteb. This method then writes the byte to the output stream, blocking until the byte is actually written.- Overrides:
- writein 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)
 
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writepublic void write(byte[] b, int off, int len) throws IOExceptionUpdates 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 (seeon), this method callsupdateon 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:
- writein class- FilterOutputStream
- Parameters:
- b- the array containing the subarray to be used for updating and writing to the output stream.
- off- the offset into- bof 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)
 
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onpublic void on(boolean on) Turns the digest function on or off. The default is on. When it is on, a call to one of thewritemethods 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.
 
 
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