Java properties

The format java.util.Properties and ResourceBundle read, also used by Spring's messages_{locale}.properties.

# Home screen
home.title=Bon retour
home.greeting=Bonjour, {0} !
cart.summary = Vous avez {0} articles \
    dans votre panier

KeysCopy Anchor Link

Each logical line is one key. The whole left-hand side is the key name, dots included; keys are never nested.

• The separator is =, : or the first run of whitespace. Whitespace around an = or : is ignored.
• A line whose first non-blank character is # or ! is a comment and is not imported.
• A line ending in an odd number of backslashes continues on the next line. The backslash is dropped, and so is the next line's leading whitespace.
• A key that appears twice is an error.

EscapesCopy Anchor Link

Import decodes \n, \t, \r, \f, \\, \uXXXX, and the escaped separators \=, \:, \#, \! and \ (space). Any other backslash is dropped, as Java does. A malformed \u escape is an error.

The file must be UTF-8. Older files that store accented characters as raw Latin-1 bytes are rejected; files that use \uXXXX escapes for them are plain ASCII and read fine.

PluralsCopy Anchor Link

Properties files have no plural construct. Plural keys are left out of an export. A MessageFormat choice pattern ({0,choice,0#no files|1#one file|1<{0} files}) is an ordinary string and is written back unchanged.

PlaceholdersCopy Anchor Link

MessageFormat arguments ({0}, {1,number}) and %s-style specifiers are kept as written. See Placeholders.

ExportCopy Anchor Link

Each key is written as key=value on its own line, in byte order. The output is pure ASCII, so it loads under a Latin-1 reader too:

• Backslashes, tabs, newlines, carriage returns and form feeds are escaped, as are =, :, # and !, and spaces that are leading or inside the key.
• Every character above U+007F, and the remaining control characters, is written as \uXXXX (characters outside the Basic Multilingual Plane as a surrogate pair).

Comments are not kept.

RelatedCopy Anchor Link

• File formats