Is there a Java parser for the Java language?

Question

I'm looking for a java library that allows me to parse a java source file and that gives me an AST representation of the code.

Actually I'm only interested in the class and method definitions with their annotations. I don't need the AST of the method code.

I'm using this information for code generation. This is why I can't compile the source file first to get the information from the resulting class file. The code wouldn't compile without errors until I generate some additional classes.

Answer 1

Java 6 supports this as a native part of the compiler and has standard APIs for it (javax.lang.model). You can read up on it here. It is designed specifically for your use-case (i.e. code generation from annotations and source).

Answer 2

ANTLR (http://www.antlr.org/) has a parser for the Java language and it also suports ASTs.

try

options {
    output=AST;
}

in the *.g file (I haven't tried it personally);