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/CharStream.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;

import org.antlr.v4.runtime.misc.Interval;

/** A source of characters for an ANTLR lexer. */
public interface CharStream extends IntStream {
	/**
	 * This method returns the text for a range of characters within this input
	 * stream. This method is guaranteed to not throw an exception if the
	 * specified {@code interval} lies entirely within a marked range. For more
	 * information about marked ranges, see {@link IntStream#mark}.
	 *
	 * @param interval an interval within the stream
	 * @return the text of the specified interval
	 *
	 * @throws NullPointerException if {@code interval} is {@code null}
	 * @throws IllegalArgumentException if {@code interval.a < 0}, or if
	 * {@code interval.b < interval.a - 1}, or if {@code interval.b} lies at or
	 * past the end of the stream
	 * @throws UnsupportedOperationException if the stream does not support
	 * getting the text of the specified interval
	 */
	public String getText(Interval interval);
}

⏎ org/antlr/v4/runtime/CharStream.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

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⇑⇑ FAQ for ANTLR Parser Generator