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/target/SwiftTarget.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.target;

import org.antlr.v4.codegen.CodeGenerator;
import org.antlr.v4.codegen.Target;
import org.antlr.v4.tool.Grammar;
import org.stringtemplate.v4.ST;
import org.stringtemplate.v4.STGroup;
import org.stringtemplate.v4.StringRenderer;

import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Locale;
import java.util.Map;
import java.util.Set;

public class SwiftTarget extends Target {
    /**
     * The Swift target can cache the code generation templates.
     */
    private static final ThreadLocal<STGroup> targetTemplates = new ThreadLocal<>();

	protected static final Map<Character, String> targetCharValueEscape;
	static {
		// https://docs.swift.org/swift-book/LanguageGuide/StringsAndCharacters.html
		HashMap<Character, String> map = new HashMap<>();
		addEscapedChar(map, '\0', '0');
		addEscapedChar(map, '\\');
		addEscapedChar(map, '\t', 't');
		addEscapedChar(map, '\n', 'n');
		addEscapedChar(map, '\r', 'r');
		addEscapedChar(map, '\"');
		addEscapedChar(map, '\'');
		targetCharValueEscape = map;
	}

    protected static final HashSet<String> reservedWords = new HashSet<>(Arrays.asList(
            "associatedtype", "class", "deinit", "enum", "extension", "func", "import", "init", "inout", "internal",
            "let", "operator", "private", "protocol", "public", "static", "struct", "subscript", "typealias", "var",
            "break", "case", "continue", "default", "defer", "do", "else", "fallthrough", "for", "guard", "if",
            "in", "repeat", "return", "switch", "where", "while",
            "as", "catch", "dynamicType", "false", "is", "nil", "rethrows", "super", "self", "Self", "throw", "throws",
            "true", "try", "__COLUMN__", "__FILE__", "__FUNCTION__","__LINE__", "#column", "#file", "#function", "#line", "_" , "#available", "#else", "#elseif", "#endif", "#if", "#selector",
            "associativity", "convenience", "dynamic", "didSet", "final", "get", "infix", "indirect", "lazy",
            "left", "mutating", "none", "nonmutating", "optional", "override", "postfix", "precedence",
            "prefix", "Protocol", "required", "right", "set", "Type", "unowned", "weak", "willSet",

             "rule", "parserRule"
	));

    public SwiftTarget(CodeGenerator gen) {
        super(gen);
    }

	@Override
	public Map<Character, String> getTargetCharValueEscape() {
		return targetCharValueEscape;
	}

	@Override
	protected Set<String> getReservedWords() {
		return reservedWords;
	}

	@Override
	protected String escapeWord(String word) {
		return "`" + word + "`";
	}

    @Override
    protected void genFile(Grammar g, ST outputFileST, String fileName) {
        super.genFile(g,outputFileST,fileName);
    }

    @Override
    protected STGroup loadTemplates() {
        STGroup result = targetTemplates.get();
        if (result == null) {
            result = super.loadTemplates();
            result.registerRenderer(String.class, new SwiftStringRenderer(), true);
            targetTemplates.set(result);
        }

        return result;
    }

    protected static class SwiftStringRenderer extends StringRenderer {
        @Override
        public String toString(Object o, String formatString, Locale locale) {
            if ("java-escape".equals(formatString)) {
                // 5C is the hex code for the \ itself
                return ((String)o).replace("\\u", "\\u005Cu");
            }

            return super.toString(o, formatString, locale);
        }
    }

	@Override
	public boolean isATNSerializedAsInts() {
		return true;
	}

	@Override
	protected String escapeChar(int v) {
		return String.format("\\u{%X}", v);
	}
}

⏎ org/antlr/v4/codegen/target/SwiftTarget.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