ANTLR is a powerful parser generator for multiple programming languages including Java.

ANTLR contains 2 major modules:

• Runtime - For building and executing parsers/lexers generated in Java.
• Tool (The Parser Generator) - For generating parsers/lexers Java class.

ANTLR Tool Source Code files are provided in the distribution packge (antlr4-4.10.1.zip). You can download them at ANTLR Website.

You can also browse the source code below:

⏎ org/antlr/v4/codegen/model/RuleElement.java

/*
 * Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD 3-clause license that
 * can be found in the LICENSE.txt file in the project root.
 */

package org.antlr.v4.codegen.model;

import org.antlr.v4.codegen.OutputModelFactory;
import org.antlr.v4.tool.ast.GrammarAST;

public class RuleElement extends SrcOp {
	/** Associated ATN state for this rule elements (action, token, ruleref, ...) */
	public int stateNumber;

	public RuleElement(OutputModelFactory factory, GrammarAST ast) {
		super(factory, ast);
		if ( ast != null && ast.atnState!=null ) stateNumber = ast.atnState.stateNumber;
	}

}

⏎ org/antlr/v4/codegen/model/RuleElement.java

Or download all of them as a single archive file:

File name: antlr-tool-4.10.1-sources.jar
File size: 347718 bytes
Release date: 2022-04-15
Download 

⇒ Donwload antlr4-4.10.1.zip

⇐ ANTLR Runtime Source Code

⇑ Download and Review ANTLR Parser Generator

⇑⇑ FAQ for ANTLR Parser Generator