10.2.1 Java Bison Interface

(The current Java interface is experimental and may evolve. More user feedback will help to stabilize it.)

The Java parser skeletons are selected using the %language "Java" directive or the ‘-L java’/‘--language=java’ option.

When generating a Java parser, bison basename.y will create a single Java source file named ‘basename.java’. Using an input file without a ‘.y’ suffix is currently broken. The basename of the output file can be changed by the %file-prefix directive or the ‘-p’/‘--name-prefix’ option. The entire output file name can be changed by the %output directive or the ‘-o’/‘--output’ option. The output file contains a single class for the parser.

You can create documentation for generated parsers using Javadoc.

Contrary to C parsers, Java parsers do not use global variables; the state of the parser is always local to an instance of the parser class. Therefore, all Java parsers are “pure”, and the %pure-parser and %define api.pure directives does not do anything when used in Java.

Push parsers are currently unsupported in Java and %define api.push_pull have no effect.

GLR parsers are currently unsupported in Java. Do not use the glr-parser directive.

No header file can be generated for Java parsers. Do not use the %defines directive or the ‘-d’/‘--defines’ options.

Currently, support for debugging and verbose errors are always compiled in. Thus the %debug and %token-table directives and the ‘-t’/‘--debug’ and ‘-k’/‘--token-table’ options have no effect. This may change in the future to eliminate unused code in the generated parser, so use %debug and %verbose-error explicitly if needed. Also, in the future the %token-table directive might enable a public interface to access the token names and codes.