open class Base64OutputStream : FilterOutputStream
kotlin.Any
   ↳ java.io.OutputStream
   ↳ java.io.FilterOutputStream
   ↳ android.util.Base64OutputStream

An OutputStream that does Base64 encoding on the data written to it, writing the resulting data to another OutputStream.

Summary

Public constructors

Performs Base64 encoding on the data written to the stream, writing the encoded data to another OutputStream.

Public methods
open Unit

close()

Closes this output stream and releases any system resources associated with the stream.

open Unit

write(b: ByteArray!, off: Int, len: Int)

Writes len bytes from the specified byte array starting at offset off to this output stream.

open Unit

write(b: Int)

Writes the specified byte to this output stream.

Inherited functions

From class FilterOutputStream

Unit flush()

Flushes this output stream and forces any buffered output bytes to be written out to the stream.

The flush method of FilterOutputStream calls the flush method of its underlying output stream.

Unit write(b: ByteArray!)

Writes b.length bytes to this output stream.

The write method of FilterOutputStream calls its write method of three arguments with the arguments b, 0, and b.length.

Note that this method does not call the one-argument write method of its underlying output stream with the single argument b.

From class OutputStream

OutputStream! nullOutputStream()

Returns a new OutputStream which discards all bytes. The returned stream is initially open. The stream is closed by calling the close() method. Subsequent calls to close() have no effect.

While the stream is open, the write(int), write(byte[]), and write(byte[], int, int) methods do nothing. After the stream has been closed, these methods all throw IOException.

The flush() method does nothing.

Inherited properties

From class FilterOutputStream

OutputStream! out

The underlying output stream to be filtered.

Public constructors

Base64OutputStream

Base64OutputStream(
    out: OutputStream!,
    flags: Int)

Performs Base64 encoding on the data written to the stream, writing the encoded data to another OutputStream.

Parameters
out OutputStream!: the OutputStream to write the encoded data to
flags Int: bit flags for controlling the encoder; see the constants in Base64

Public methods

close

open fun close(): Unit

Closes this output stream and releases any system resources associated with the stream.

When not already closed, the close method of FilterOutputStream calls its flush method, and then calls the close method of its underlying output stream.

Exceptions
java.lang.Exception if this resource cannot be closed
java.io.IOException if an I/O error occurs.

write

open fun write(
    b: ByteArray!,
    off: Int,
    len: Int
): Unit

Writes len bytes from the specified byte array starting at offset off to this output stream.

The write method of FilterOutputStream calls the write method of one argument on each byte to output.

Note that this method does not call the write method of its underlying output stream with the same arguments. Subclasses of FilterOutputStream should provide a more efficient implementation of this method.

Parameters
b ByteArray!: the data.
off Int: the start offset in the data.
len Int: the number of bytes to write.
Exceptions
java.io.IOException if an I/O error occurs.

write

open fun write(b: Int): Unit

Writes the specified byte to this output stream.

The write method of FilterOutputStream calls the write method of its underlying output stream, that is, it performs out.write(b).

Implements the abstract write method of OutputStream.

Parameters
b Int: the byte.
Exceptions
java.io.IOException if an I/O error occurs.

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Last updated 2026-02-13 UTC.