org.apache.commons.codec.net
Class BCodec

java.lang.Object
  org.apache.commons.codec.net.BCodec

All Implemented Interfaces:

Decoder, Encoder, StringDecoder, StringEncoder

public class BCodec
extends Object
implements StringEncoder, StringDecoder

Identical to the Base64 encoding defined by RFC 1521 and allows a character set to be specified.

RFC 1522 describes techniques to allow the encoding of non-ASCII text in various portions of a RFC 822 [2] message header, in a manner which is unlikely to confuse existing message handling software.

Since:

1.3

Version:

$Id: BCodec.java,v 1.5 2004/04/13 22:46:37 ggregory Exp $

Author:

Apache Software Foundation

See Also:

MIME (Multipurpose Internet Mail Extensions) Part Two: Message Header Extensions for Non-ASCII Text

Constructor Summary

BCodec()
Default constructor.

BCodec(String charset)
Constructor which allows for the selection of a default charset

Method Summary

Object	decode(Object value) Decodes a Base64 object into its original form.
String	decode(String value) Decodes a Base64 string into its original form.
protected String	decodeText(String text) Applies an RFC 1522 compliant decoding scheme to the given string of text.
protected byte[]	doDecoding(byte[] bytes) Decodes an array of bytes using the defined encoding scheme
protected byte[]	doEncoding(byte[] bytes) Encodes an array of bytes using the defined encoding scheme
Object	encode(Object value) Encodes an object into its Base64 form using the default charset.
String	encode(String value) Encodes a string into its Base64 form using the default charset.
String	encode(String value, String charset) Encodes a string into its Base64 form using the specified charset.
protected String	encodeText(String text, String charset) Applies an RFC 1522 compliant encoding scheme to the given string of text with the given charset.
String	getDefaultCharset() The default charset used for string decoding and encoding.
protected String	getEncoding() Returns the codec name (referred to as encoding in the RFC 1522)

Methods inherited from class java.lang.Object

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

Constructor Detail

BCodec

public BCodec()

Default constructor.

BCodec

public BCodec(String charset)

Constructor which allows for the selection of a default charset

Parameters:

charset - the default string charset to use.

See Also:

JRE character encoding names

Method Detail

getEncoding

protected String getEncoding()

Returns the codec name (referred to as encoding in the RFC 1522)

Returns:

name of the codec

doEncoding

protected byte[] doEncoding(byte[] bytes)
                     throws EncoderException

Encodes an array of bytes using the defined encoding scheme

Parameters:

bytes - Data to be encoded

Returns:

A byte array containing the encoded data

Throws:

EncoderException - thrown if the Encoder encounters a failure condition during the encoding process.

doDecoding

protected byte[] doDecoding(byte[] bytes)
                     throws DecoderException

Decodes an array of bytes using the defined encoding scheme

Parameters:

bytes - Data to be decoded

Returns:

a byte array that contains decoded data

Throws:

DecoderException - A decoder exception is thrown if a Decoder encounters a failure condition during the decode process.

encode

public String encode(String value,
                     String charset)
              throws EncoderException

Encodes a string into its Base64 form using the specified charset. Unsafe characters are escaped.

Parameters:

value - string to convert to Base64 form

charset - the charset for pString

Returns:

Base64 string

Throws:

EncoderException - thrown if a failure condition is encountered during the encoding process.

encode

public String encode(String value)
              throws EncoderException

Encodes a string into its Base64 form using the default charset. Unsafe characters are escaped.

Specified by:

encode in interface StringEncoder

Parameters:

value - string to convert to Base64 form

Returns:

Base64 string

Throws:

EncoderException - thrown if a failure condition is encountered during the encoding process.

decode

public String decode(String value)
              throws DecoderException

Decodes a Base64 string into its original form. Escaped characters are converted back to their original representation.

Specified by:

decode in interface StringDecoder

Parameters:

value - Base64 string to convert into its original form

Returns:

original string

Throws:

DecoderException - A decoder exception is thrown if a failure condition is encountered during the decode process.

encode

public Object encode(Object value)
              throws EncoderException

Encodes an object into its Base64 form using the default charset. Unsafe characters are escaped.

Specified by:

encode in interface Encoder

Parameters:

value - object to convert to Base64 form

Returns:

Base64 object

Throws:

EncoderException - thrown if a failure condition is encountered during the encoding process.

decode

public Object decode(Object value)
              throws DecoderException

Decodes a Base64 object into its original form. Escaped characters are converted back to their original representation.

Specified by:

decode in interface Decoder

Parameters:

value - Base64 object to convert into its original form

Returns:

original object

Throws:

DecoderException - A decoder exception is thrown if a failure condition is encountered during the decode process.

getDefaultCharset

public String getDefaultCharset()

The default charset used for string decoding and encoding.

Returns:

the default string charset.

encodeText

protected String encodeText(String text,
                            String charset)
                     throws EncoderException,
                            UnsupportedEncodingException

Applies an RFC 1522 compliant encoding scheme to the given string of text with the given charset. This method constructs the "encoded-word" header common to all the RFC 1522 codecs and then invokes doEncoding(byte []) method of a concrete class to perform the specific enconding.

Parameters:

text - a string to encode

charset - a charset to be used

Returns:

RFC 1522 compliant "encoded-word"

Throws:

EncoderException - thrown if there is an error conidition during the Encoding process.

UnsupportedEncodingException - thrown if charset is not supported

See Also:

JRE character encoding names

decodeText

protected String decodeText(String text)
                     throws DecoderException,
                            UnsupportedEncodingException

Applies an RFC 1522 compliant decoding scheme to the given string of text. This method processes the "encoded-word" header common to all the RFC 1522 codecs and then invokes doEncoding(byte []) method of a concrete class to perform the specific deconding.

Parameters:

text - a string to decode

Throws:

DecoderException - thrown if there is an error conidition during the Decoding process.

UnsupportedEncodingException - thrown if charset specified in the "encoded-word" header is not supported