Utility class for HTML form encoding. This class contains static methods for converting a String to the
application/x-www-form-urlencoded
MIME format. For more information about HTML form encoding, consult the HTML
specification.
When encoding a String, the following rules apply:
- The alphanumeric characters "
a
" through "z
", "A
" through "Z
" and "0
" through "9
" remain the same.
- The special characters "
.
", "-
", "*
", and "_
" remain the same.
- The space character " " is converted into a plus sign "
+
".
- All other characters are unsafe and are first converted into one or more bytes using some encoding scheme. Then each byte is represented by the 3-character string "
%xy
", where xy is the two-digit hexadecimal representation of the byte. The recommended encoding scheme to use is UTF-8. However, for compatibility reasons, if an encoding is not specified, then the default encoding of the platform is used.
For example using UTF-8 as the encoding scheme the string "The string ü@foo-bar" would get converted to "The+string+%C3%BC%40foo-bar" because in UTF-8 the character ü is encoded as two bytes C3 (hex) and BC (hex), and the character @ is encoded as one byte 40 (hex).