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 Runtime 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/runtime/misc/AbstractEqualityComparator.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.runtime.misc;

/**
 * This abstract base class is provided so performance-critical applications can
 * use virtual- instead of interface-dispatch when calling comparator methods.
 *
 * @author Sam Harwell
 */
public abstract class AbstractEqualityComparator<T> implements EqualityComparator<T> {

}

⏎ org/antlr/v4/runtime/misc/AbstractEqualityComparator.java

Or download all of them as a single archive file:

File name: antlr-runtime-4.10.1-sources.jar
File size: 308953 bytes
Release date: 2022-04-15
Download 

⇒ ANTLR Tool Source Code

⇐ What Is ANTLR Parser Generator

⇑ Download and Review ANTLR Parser Generator

⇑⇑ FAQ for ANTLR Parser Generator