Using ANTLR2 with Java 21

[gurucubano]

Hello,
We have an historical Java written application for a search engine, using since ages ANTLR2 and the AST produced by it. We now want to move with all the code to Java21, but the ANTLR2 part does not compile anymore. It compiles fine a test. pgm, like:

package org.company.test;

import antlr.RecognitionException;
import antlr.TokenStreamException;
import antlr.collections.AST;
import com.sisis.infoguide.query.InfoGuideQueryLexer;
import com.sisis.infoguide.query.InfoGuideQueryParser;

import java.io.StringReader;

public class GrammarTests {
    public static void main(String argv[]) throws TokenStreamException, RecognitionException {
        System.out.println("Running Grammar Tests");
        parseGrammarQuery("-1=\"perl\"");
        parseGrammarQuery("-1=\"perl\" OR 331=\"titel\"");
        //...
    }

    private static void parseGrammarQuery(String queryString) throws TokenStreamException, RecognitionException {
        StringReader queryInpStream = new StringReader(queryString);
        InfoGuideQueryLexer lexer = new InfoGuideQueryLexer(queryInpStream);
        InfoGuideQueryParser parser = new InfoGuideQueryParser(lexer);
        parser.info_guide_query();
        AST aAst = parser.getAST();
        System.out.println(aAst.toStringTree());
    }

compiling and running this with Java 17 gives:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/amazon-corretto-17.jdk//Contents/Home
mvn clean
mvn install

java \
   -Dfile.encoding=UTF-8 \
   -classpath /Users/apitzm/ANTLR/queryGrammar/target/classes:/Users/apitzm/.m2/repository/antlr/antlr/2.7.7/antlr-2.7.7.jar \
   org.company.test.GrammarTests

Running Grammar Tests
 ( = -1 perl )
 ( OR ( = -1 perl ) ( = 331 titel ) )
...

So far so good.

But with Java21 it gives:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/amazon-corretto-21.jdk//Contents/Home
mvn install
[INFO] Scanning for projects...
[INFO]
[INFO] ------------< com.sisis.infoguide:infoguide-query-grammar >-------------
[INFO] Building InfoGuide Query Grammar 7.4
[INFO]   from pom.xml
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- antlr:2.2:generate (default) @ infoguide-query-grammar ---
[INFO] performing grammar generation [InfoGuideQuery.g]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  0.220 s
[INFO] Finished at: 2024-09-24T13:03:01+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.codehaus.mojo:antlr-maven-plugin:2.2:generate (default) on project infoguide-query-grammar: Execution default of goal org.codehaus.mojo:antlr-maven-plugin:2.2:generate failed: The Security Manager is deprecated and will be removed in a future release -> [Help 1]
[ERROR]

Is there a way to fix this without moving to ANTLR4, i.e. rewriting the two *.g as *.g4 and writing a new visitor to get the AST again?

[gurucubano]

I fixed this with the Debian.org pkg from https://tracker.debian.org/news/1556607/accepted-antlr-maven-plugin-22-6-source-into-unstable/
With this it compiles fine with Java 21.