org.apache.kerby.util

Class Base64OutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

org.apache.kerby.util.Base64OutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class Base64OutputStream
extends FilterOutputStream

Provides Base64 encoding and decoding in a streaming fashion (unlimited size). When encoding the default lineLength is 76 characters and the default lineEnding is CRLF, but these can be overridden by using the appropriate constructor.

The default behaviour of the Base64OutputStream is to ENCODE, whereas the default behaviour of the Base64InputStream is to DECODE. But this behaviour can be overridden by using a different constructor.

This class implements section 6.8. Base64 Content-Transfer-Encoding from RFC 2045 Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies by Freed and Borenstein.

Since this class operates directly on byte streams, and not character streams, it is hard-coded to only encode/decode character encodings which are compatible with the lower 127 ASCII chart (ISO-8859-1, Windows-1252, UTF-8, etc).

Since:

1.4

Version:

$Id$

Author:

Apache Software Foundation

See Also:

RFC 2045

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
Base64OutputStream(OutputStream out) Creates a Base64OutputStream such that all data written is Base64-encoded to the original provided OutputStream.
Base64OutputStream(OutputStream out, boolean doEncode) Creates a Base64OutputStream such that all data written is either Base64-encoded or Base64-decoded to the original provided OutputStream.
Base64OutputStream(OutputStream out, boolean doEncode, int lineLength, byte[] lineSeparator) Creates a Base64OutputStream such that all data written is either Base64-encoded or Base64-decoded to the original provided OutputStream.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes this output stream and releases any system resources associated with the stream.
void	flush() Flushes this output stream and forces any buffered output bytes to be written out to the stream.
void	write(byte[] b, int offset, int len) Writes len bytes from the specified b array starting at offset to this output stream.
void	write(int i) Writes the specified byte to this output stream.

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Base64OutputStream

public Base64OutputStream(OutputStream out)

Creates a Base64OutputStream such that all data written is Base64-encoded to the original provided OutputStream.

Parameters:

out - OutputStream to wrap.

Base64OutputStream

public Base64OutputStream(OutputStream out,
                  boolean doEncode)

Creates a Base64OutputStream such that all data written is either Base64-encoded or Base64-decoded to the original provided OutputStream.

Parameters:

out - OutputStream to wrap.

doEncode - true if we should encode all data written to us, false if we should decode.

Base64OutputStream

public Base64OutputStream(OutputStream out,
                  boolean doEncode,
                  int lineLength,
                  byte[] lineSeparator)

Creates a Base64OutputStream such that all data written is either Base64-encoded or Base64-decoded to the original provided OutputStream.

Parameters:

out - OutputStream to wrap.

doEncode - true if we should encode all data written to us, false if we should decode.

lineLength - If doEncode is true, each line of encoded data will contain lineLength characters (rounded down to nearest multiple of 4). If lineLength <=0, the encoded data is not divided into lines. If doEncode is false, lineLength is ignored.

lineSeparator - If doEncode is true, each line of encoded data will be terminated with this byte sequence (e.g. \r\n). If lineLength <= 0, the lineSeparator is not used. If doEncode is false lineSeparator is ignored.

Method Detail

write

public void write(int i)
           throws IOException

Writes the specified byte to this output stream.

Overrides:

write in class FilterOutputStream

Parameters:

i - source byte

Throws:

IOException - if an I/O error occurs.

write

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

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

Overrides:

write in class FilterOutputStream

Parameters:

b - source byte array

offset - where to start reading the bytes

len - maximum number of bytes to write

Throws:

IOException - if an I/O error occurs.

NullPointerException - if the byte array parameter is null

IndexOutOfBoundsException - if offset, len or buffer size are invalid

flush

public void flush()
           throws IOException

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

Specified by:

flush in interface Flushable

Overrides:

flush in class FilterOutputStream

Throws:

IOException - if an I/O error occurs.

close

public void close()
           throws IOException

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

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class FilterOutputStream

Throws:

IOException - if an I/O error occurs.