Contents - Cultural View

.properties 22
.properties
Filename
extension
Type of format ASCII
.properties
.properties is a file extension for files mainly used in Java related technologies to store the configurable parameters
of an application. They can also be used for storing strings for Internationalization and localization; these are known
as Property Resource Bundles.
Each parameter is stored as a pair of strings, one storing the name of the parameter (called the key), and the other
storing the value.
Format
Each line in a .properties file normally stores a single property. Several formats are possible for each line, including
key=value, key = value, key:value, and key value.
.properties files can use the number sign (#) or the exclamation mark (!) as the first non blank character in a line to
denote that all text following it is a comment. The backwards slash is used to escape a character. An example of a
properties file is provided below.
# You are reading the ".properties" entry.
! The exclamation mark can also mark text as comments.
website = http://en.wikipedia.org/
language = English
# The backslash below tells the application to continue reading
# the value onto the next line.
message = Welcome to \
Wikipedia!
# Add spaces to the key
key\ with\ spaces = This is the value that could be looked up with the key "key with spaces".
# Unicode
tab : \u0009
In the example above, website would be a key, and its corresponding value would be
http://en.wikipedia.org/. While the number sign and the exclamation mark marks text as comments, it
has no effect when it is part of a property. Thus, the key message has the value Welcome to Wikipedia!
and not Welcome to Wikipedia. Note also that all of the whitespace in front of Wikipedia! is excluded
completely.
The encoding of a .properties file is ISO-8859-1, also known as Latin-1. All non-Latin-1 characters must be entered
by using Unicode escape characters, e. g. \uHHHH where HHHH is a hexadecimal index of the character in the
Unicode character set. This allows for using .properties files as resource bundles for localization. A non-Latin-1 text
file can be converted to a correct .properties file by using the native2ascii tool that is shipped with the JDK or by
using a tool, such as po2prop [1] , that manages the transformation from a bilingual localization format into .properties
escaping.