Added in API level 1

DigestInputStream

open class DigestInputStream : FilterInputStream
kotlin.Any
   ↳ java.io.InputStream
   ↳ java.io.FilterInputStream
   ↳ java.security.DigestInputStream

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 input stream's #read() methods.

It is possible to turn this stream on or off (see on). When it is on, a call to one of the read 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.

Note that digest objects can compute only one digest (see MessageDigest), so that in order to compute intermediate digests, a caller should retain a handle onto the digest object, and clone it for each digest to be computed, leaving the original digest untouched.

Summary

Public constructors

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

Public methods
open MessageDigest!

Returns the message digest associated with this stream.

open Unit
on(on: Boolean)

Turns the digest function on or off.

open Int

Reads a byte, and updates the message digest (if the digest function is on).

open Int
read(b: ByteArray!, off: Int, len: Int)

Reads into a byte array, and updates the message digest (if the digest function is on).

open Unit

Associates the specified message digest with this stream.

open String

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

Inherited functions
Properties
MessageDigest!

The message digest associated with this stream.

Inherited properties

Public constructors

DigestInputStream

Added in API level 1
DigestInputStream(
    stream: InputStream!,
    digest: MessageDigest!)

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

Parameters
stream InputStream!: the input stream.
digest MessageDigest!: the message digest to associate with this stream.

Public methods

getMessageDigest

Added in API level 1
open fun getMessageDigest(): MessageDigest!

Returns the message digest associated with this stream.

Return
MessageDigest! the message digest associated with this stream.

on

Added in API level 1
open fun on(on: Boolean): Unit

Turns the digest function on or off. The default is on. When it is on, a call to one of the read 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.

read

Added in API level 1
open fun read(): Int

Reads a byte, and updates the message digest (if the digest function is on). That is, this method reads a byte from the input stream, blocking until the byte is actually read. If the digest function is on (see on), this method will then call update on the message digest associated with this stream, passing it the byte read.

Return
Int the byte read.
Exceptions
java.io.IOException if an I/O error occurs.
java.io.IOException if an I/O error occurs.

read

Added in API level 1
open fun read(
    b: ByteArray!,
    off: Int,
    len: Int
): Int

Reads into a byte array, and updates the message digest (if the digest function is on). That is, this method reads up to len bytes from the input stream into the array b, starting at offset off. This method blocks until the data is actually read. If the digest function is on (see on), this method will then call update on the message digest associated with this stream, passing it the data.

Parameters
b ByteArray!: the array into which the data is read.
off Int: the starting offset into b of where the data should be placed.
len Int: the maximum number of bytes to be read from the input stream into b, starting at offset off.
Return
Int the actual number of bytes read. This is less than len if the end of the stream is reached prior to reading len bytes. -1 is returned if no bytes were read because the end of the stream had already been reached when the call was made.
Exceptions
java.io.IOException If the first byte cannot be read for any reason other than end of file, or if the input stream has been closed, or if some other I/O error occurs.
java.lang.NullPointerException If b is null.
java.lang.IndexOutOfBoundsException If off is negative, len is negative, or len is greater than b.length - off
java.io.IOException if an I/O error occurs.

setMessageDigest

Added in API level 1
open fun setMessageDigest(digest: MessageDigest!): Unit

Associates the specified message digest with this stream.

Parameters
digest MessageDigest!: the message digest to be associated with this stream.

toString

Added in API level 1
open fun toString(): String

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

Return
String a string representation of the object.

Properties

digest

Added in API level 1
protected var digest: MessageDigest!

The message digest associated with this stream.