ANTLR - Java source tree walker

Java 1.5 grammar for ANTLR v3 that builds trees
 
Dieter Habelitz - A Java 1.5 grammar that builds trees and a tree grammar. Not derived from Java grammar Terence wrote.
original link broken - http://www.antlr3.org/grammar/1207932239307/Java1_5Grammars

Try this on  github
https://github.com/grammarware/slps/tree/master/topics/grammars/java-5/habelitz

Compile grammars

java org.antlr.Tool -o generated Java.g
java org.antlr.Tool -o generated JavaTreeParser.g

Creates following files:

 ls -l generated/
total 1588
-rw-------. 1 dave vesedan  145133 Jan 29 12:20 JavaLexer.java
-rw-------. 1 dave vesedan 1046974 Jan 29 12:20 JavaParser.java
-rw-r--r--. 1 dave vesedan    3687 Jan 29 12:10 Java.tokens
-rw-r--r--. 1 dave vesedan  386412 Jan 29 13:11 JavaTreeParser.java
-rw-r--r--. 1 dave vesedan    3687 Jan 29 13:11 JavaTreeParser.tokens

import generated.JavaLexer;
import generated.JavaParser;
import generated.JavaTreeParser;

import org.antlr.runtime.ANTLRFileStream;
import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.tree.CommonTree;
import org.antlr.runtime.tree.CommonTreeNodeStream;


public class JavaTreeWalker {
    
    public static void main(String[] args) throws Exception {
        
        ANTLRFileStream input = new ANTLRFileStream(args[0]);
        
        JavaLexer lexer = new JavaLexer(input);
        
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        
        JavaParser parser = new JavaParser(tokens);
        
        JavaParser.javaSource_return r = parser.javaSource();
        
        CommonTree t = (CommonTree)r.getTree();
        
        System.out.println(t.toStringTree());
        
        CommonTreeNodeStream nodes = new CommonTreeNodeStream(t);
        
        nodes.setTokenStream(tokens);
        
        JavaTreeParser walker = new JavaTreeParser(nodes);
        
        System.out.println("\nWalk tree:\n");
        
        walker.javaSource();
        
        System.out.println(tokens.toString());
        
    }

}

(JAVA_SOURCE ANNOTATION_LIST (import (. generated JavaLexer)) (import (. generated JavaParser)) (import (. generated JavaTreeParser)) (import (. (. (. org antlr) runtime) ANTLRFileStream)) (import (. (. (. org antlr) runtime) CommonTokenStream)) (import (. (. (. (. org antlr) runtime) tree) CommonTree)) (import (. (. (. (. org antlr) runtime) tree) CommonTreeNodeStream)) (class (MODIFIER_LIST public) JavaTreeWalker (CLASS_TOP_LEVEL_SCOPE (VOID_METHOD_DECL (MODIFIER_LIST public static) main (FORMAL_PARAM_LIST (FORMAL_PARAM_STD_DECL LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT String) (ARRAY_DECLARATOR_LIST ARRAY_DECLARATOR)) args)) (THROWS_CLAUSE Exception) (BLOCK_SCOPE (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT ANTLRFileStream)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR input (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT ANTLRFileStream) (ARGUMENT_LIST (EXPR (ARRAY_ELEMENT_ACCESS args (EXPR 0))))))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT JavaLexer)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR lexer (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT JavaLexer) (ARGUMENT_LIST (EXPR input))))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT CommonTokenStream)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR tokens (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT CommonTokenStream) (ARGUMENT_LIST (EXPR lexer))))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT JavaParser)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR parser (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT JavaParser) (ARGUMENT_LIST (EXPR tokens))))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT JavaParser javaSource_return)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR r (EXPR (METHOD_CALL (. parser javaSource) ARGUMENT_LIST))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT CommonTree)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR t (EXPR (CAST_EXPR (TYPE (QUALIFIED_TYPE_IDENT CommonTree)) (METHOD_CALL (. r getTree) ARGUMENT_LIST)))))) (EXPR (METHOD_CALL (. (. System out) println) (ARGUMENT_LIST (EXPR (METHOD_CALL (. t toStringTree) ARGUMENT_LIST))))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT CommonTreeNodeStream)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR nodes (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT CommonTreeNodeStream) (ARGUMENT_LIST (EXPR t))))))) (EXPR (METHOD_CALL (. nodes setTokenStream) (ARGUMENT_LIST (EXPR tokens)))) (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT JavaTreeParser)) (VAR_DECLARATOR_LIST (VAR_DECLARATOR walker (EXPR (STATIC_ARRAY_CREATOR (QUALIFIED_TYPE_IDENT JavaTreeParser) (ARGUMENT_LIST (EXPR nodes))))))) (EXPR (METHOD_CALL (. (. System out) println) (ARGUMENT_LIST (EXPR "\nWalk tree:\n")))) (EXPR (METHOD_CALL (. walker javaSource) ARGUMENT_LIST)) (EXPR (METHOD_CALL (. (. System out) println) (ARGUMENT_LIST (EXPR (METHOD_CALL (. tokens toString) ARGUMENT_LIST))))))))))

Walk tree:

importgenerated.JavaLexer;importgenerated.JavaParser;importgenerated.JavaTreeParser;importorg.antlr.runtime.ANTLRFileStream;importorg.antlr.runtime.CommonTokenStream;importorg.antlr.runtime.tree.CommonTree;importorg.antlr.runtime.tree.CommonTreeNodeStream;publicclassJavaTreeWalker{publicstaticvoidmain(String[]args)throwsException{ANTLRFileStreaminput=newANTLRFileStream(args[0]);JavaLexerlexer=newJavaLexer(input);CommonTokenStreamtokens=newCommonTokenStream(lexer);JavaParserparser=newJavaParser(tokens);JavaParser.javaSource_returnr=parser.javaSource();CommonTreet=(CommonTree)r.getTree();System.out.println(t.toStringTree());CommonTreeNodeStreamnodes=newCommonTreeNodeStream(t);nodes.setTokenStream(tokens);JavaTreeParserwalker=newJavaTreeParser(nodes);System.out.println("\nWalk tree:\n");walker.javaSource();System.out.println(tokens.toString());}}

HelloWorld Java program

public class HelloWord {

  static int x;

  public static void main(String args[]){
    
    int y;

    System.out.println("Hello,world!");

  }

}

AST text output

(JAVA_SOURCE ANNOTATION_LIST (class (MODIFIER_LIST public) HelloWorld (CLASS_TOP_LEVEL_SCOPE (VAR_DECLARATION (MODIFIER_LIST static) (TYPE int) (VAR_DECLARATOR_LIST (VAR_DECLARATOR x))) (VOID_METHOD_DECL (MODIFIER_LIST public static) main (FORMAL_PARAM_LIST (FORMAL_PARAM_STD_DECL LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT String)) (args (ARRAY_DECLARATOR_LIST ARRAY_DECLARATOR)))) (BLOCK_SCOPE (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE int) (VAR_DECLARATOR_LIST (VAR_DECLARATOR y))) (EXPR (METHOD_CALL (. (. System out) println) (ARGUMENT_LIST (EXPR "Hello,world!")))))))))

Walk tree:

publicclassHelloWorld{staticintx;publicstaticvoidmain(Stringargs[]){inty;System.out.println("Hello,world!");}}

With option to keep whitespace set in Java.g

public boolean preserveWhitespacesAndComments = true;

(JAVA_SOURCE ANNOTATION_LIST (class (MODIFIER_LIST public) HelloWorld (CLASS_TOP_LEVEL_SCOPE (VAR_DECLARATION (MODIFIER_LIST static) (TYPE int) (VAR_DECLARATOR_LIST (VAR_DECLARATOR x))) (VOID_METHOD_DECL (MODIFIER_LIST public static) main (FORMAL_PARAM_LIST (FORMAL_PARAM_STD_DECL LOCAL_MODIFIER_LIST (TYPE (QUALIFIED_TYPE_IDENT String)) (args (ARRAY_DECLARATOR_LIST ARRAY_DECLARATOR)))) (BLOCK_SCOPE (VAR_DECLARATION LOCAL_MODIFIER_LIST (TYPE int) (VAR_DECLARATOR_LIST (VAR_DECLARATOR y))) (EXPR (METHOD_CALL (. (. System out) println) (ARGUMENT_LIST (EXPR "Hello,world!")))))))))

Walk tree:

public class HelloWorld {

  static int x;

  public static void main(String args[]){
    
    int y;

    System.out.println("Hello,world!");

  }

}

AST generated in ANTLR-Works