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/SerializedJavaATN.java

package org.antlr.v4.codegen.model;

import org.antlr.v4.codegen.OutputModelFactory;
import org.antlr.v4.codegen.Target;
import org.antlr.v4.runtime.atn.ATN;
import org.antlr.v4.runtime.atn.ATNDeserializer;
import org.antlr.v4.runtime.atn.ATNSerializer;
import org.antlr.v4.runtime.misc.IntegerList;

/** A serialized ATN for the java target, which requires we use strings and 16-bit unicode values */
public class SerializedJavaATN extends SerializedATN {
	private final String[] serializedAsString;
	private final String[][] segments;

	public SerializedJavaATN(OutputModelFactory factory, ATN atn) {
		super(factory);
		IntegerList data = ATNSerializer.getSerialized(atn);
		data = ATNDeserializer.encodeIntsWith16BitWords(data);

		int size = data.size();
		Target target = factory.getGenerator().getTarget();
		int segmentLimit = target.getSerializedATNSegmentLimit();
		segments = new String[(int)(((long)size + segmentLimit - 1) / segmentLimit)][];
		int segmentIndex = 0;

		for (int i = 0; i < size; i += segmentLimit) {
			int segmentSize = Math.min(i + segmentLimit, size) - i;
			String[] segment = new String[segmentSize];
			segments[segmentIndex++] = segment;
			for (int j = 0; j < segmentSize; j++) {
				segment[j] = target.encodeInt16AsCharEscape(data.get(i + j));
			}
		}

		serializedAsString = segments[0]; // serializedAsString is valid if only one segment
	}

	public Object getSerialized() { return serializedAsString; }
	public String[][] getSegments() { return segments; }
}

⏎ org/antlr/v4/codegen/model/SerializedJavaATN.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

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⇑⇑ FAQ for ANTLR Parser Generator