net.wimpi.pim.util
Class QuotedPrintable

java.lang.Object
  |
  +--net.wimpi.pim.util.QuotedPrintable

public class QuotedPrintable

extends java.lang.Object

This class provides methods for encoding and decoding data in MIME quoted-printable format, as described in RFC 2045 (Section 6.7).

QuotedPrintable is a Content-Transfer-Encoding. That is, the input to encoding is a sequence of bytes, and the output is a sequence of characters (similar to base64). It is orthogonal to the character encoding.

For example, suppose a MIME message consists of Unicode text with a Content-Type of "text/plain; charset=UTF8", and a Content-Transfer-Encoding of "quoted-printable" (this would be unusual, but valid). A MIME message should be viewed as a sequence of abstract characters, which in this case could be decoded as bytes according to the "quoted-printable" transfer encoding, and then back to a (different, in general) sequence of characters according to the "UTF8" character encoding.

The input to the encode methods is always a byte array. Strictly speaking the output represents a sequence of characters, but since these characters are from a subset of both the Unicode and ASCII character repertoires, it is possible to express the output either as a String or as a byte array.

References:

1. RFC 2045, Multipurpose Internet Mail Extensions (MIME) Part One, Format of Internet Message Bodies, "Section 6.7 Quoted-Printable Content-Transfer-Encoding," http://www.imc.org/rfc2045

2. Dan Connolly, draft-ietf-html-charset-harmful-00.txt, "Character Set" Considered Harmful, http://www.w3.org/pub/WWW/MarkUp/html-spec/charset-harmful.html

Version:

Distributed with 0.1 (22/07/2003)

Author:

Jill Baker

Method Summary

static java.lang.String	decode(java.lang.String s) Takes a quoted-printable encoding and decodes it to find the corresponding sequence of bytes.
static java.lang.String	encode(java.lang.String data) Encodes a byte array using quoted-printable encoding, and returns the result as a String.

Methods inherited from class java.lang.Object

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

Method Detail

encode

public static final java.lang.String encode(java.lang.String data)

Encodes a byte array using quoted-printable encoding, and returns the result as a String.

Line breaks in the input MUST be represented as "\r\n" - any other combination is treated as binary data. Line breaks in the output will always be represented as "\r\n".

Returns:

output in quoted-printable form.

decode

public static final java.lang.String decode(java.lang.String s)

Takes a quoted-printable encoding and decodes it to find the corresponding sequence of bytes.

Unrecognised sequences starting with '=' are passed through unmodified, as are characters that do not correspond to bytes that could have been output by a correct quoted-printable encoder. Note that this method will strip trailing whitespace from each line.

Parameters:

s - input string in quoted-printable form

Returns:

the decoded data.