Literals

Specify integer literals in decimal, octal, or hex notation. Use the following single letter designations to specify the primitive type: l for long, f for float, and d for double. If not specified, the type defaults to int (with the exception of certain assignments described later).

Grammar:

INTEGER: '-'? ( '0' | [1-9] [0-9]* ) [lLfFdD]?;
OCTAL: '-'? '0' [0-7]+ [lL]?;
HEX: '-'? '0' [xX] [0-9a-fA-F]+ [lL]?;

Examples:

0     // integer literal of 0
0D    // double literal of 0.0
1234L // long literal of 1234
-90F  // float literal of -90.0
-022  // integer literal of -18 specified in octal
0xF2A // integer literal of 3882

Specify floating point literals using the following single letter designations for the primitive type: f for float and d for double. If not specified, the type defaults to double.

Grammar:

DECIMAL: '-'? ( '0' | [1-9] [0-9]* ) (DOT [0-9]+)? ( [eE] [+\-]? [0-9]+ )? [fFdD]?;

Examples:

0.0      // double value of 0.0
1E6      // double value of 1000000
0.977777 // double value of 0.97777
-126.34  // double value of -126.34
89.9F    // float value of 89.9

Specify literal string with either single or double quotes. In double-quoted literal strings, you can escape double-quotes with a backslash to include them in the string. Similarly, you escape single quotes with a backslash in single-quoted literal strings. Backslashes themselves also need to be escaped with a backslash.

Grammar:

STRING: ( '"' ( '\\"' | '\\\\' | ~[\\"] )*? '"' ) | ( '\'' ( '\\\'' | '\\\\' | ~[\\'] )*? '\'' );

Examples:

"double-quoted String literal"
'single-quoted String literal'
"\"double-quoted String with escaped double-quotes\" and backslash: \\"
'\'single-quoted String with escaped single-quotes\' and backslash \\'
"double-quoted String with non-escaped 'single-quotes'"
'single-quoted String with non-escaped "double-quotes"'

(char)"C"
(char)'c'