org.apache.commons.ssl
Class Base64OutputStream

java.lang.Object
  extended by java.io.OutputStream
      extended by java.io.FilterOutputStream
          extended by org.apache.commons.ssl.Base64OutputStream
All Implemented Interfaces:
java.io.Closeable, java.io.Flushable

public class Base64OutputStream
extends java.io.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
private  Base64 base64
           
private  boolean doEncode
           
private  byte[] singleByte
           
 
Fields inherited from class java.io.FilterOutputStream
out
 
Constructor Summary
Base64OutputStream(java.io.OutputStream out)
          Creates a Base64OutputStream such that all data written is Base64-encoded to the original provided OutputStream.
Base64OutputStream(java.io.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(java.io.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
 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.
private  void flush(boolean propogate)
          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
 

Field Detail

doEncode

private final boolean doEncode

base64

private final Base64 base64

singleByte

private final byte[] singleByte
Constructor Detail

Base64OutputStream

public Base64OutputStream(java.io.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(java.io.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(java.io.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 java.io.IOException
Writes the specified byte to this output stream.

Overrides:
write in class java.io.FilterOutputStream
Parameters:
i - source byte
Throws:
java.io.IOException - if an I/O error occurs.

write

public void write(byte[] b,
                  int offset,
                  int len)
           throws java.io.IOException
Writes len bytes from the specified b array starting at offset to this output stream.

Overrides:
write in class java.io.FilterOutputStream
Parameters:
b - source byte array
offset - where to start reading the bytes
len - maximum number of bytes to write
Throws:
java.io.IOException - if an I/O error occurs.
java.lang.NullPointerException - if the byte array parameter is null
java.lang.IndexOutOfBoundsException - if offset, len or buffer size are invalid

flush

private void flush(boolean propogate)
            throws java.io.IOException
Flushes this output stream and forces any buffered output bytes to be written out to the stream. If propogate is true, the wrapped stream will also be flushed.

Parameters:
propogate - boolean flag to indicate whether the wrapped OutputStream should also be flushed.
Throws:
java.io.IOException - if an I/O error occurs.

flush

public void flush()
           throws java.io.IOException
Flushes this output stream and forces any buffered output bytes to be written out to the stream.

Specified by:
flush in interface java.io.Flushable
Overrides:
flush in class java.io.FilterOutputStream
Throws:
java.io.IOException - if an I/O error occurs.

close

public void close()
           throws java.io.IOException
Closes this output stream and releases any system resources associated with the stream.

Specified by:
close in interface java.io.Closeable
Overrides:
close in class java.io.FilterOutputStream
Throws:
java.io.IOException - if an I/O error occurs.