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The ANTLR 4 grammar compiler.
There is a newer version: 4.9.0
/*
 * [The "BSD license"]
 *  Copyright (c) 2012 Terence Parr
 *  Copyright (c) 2012 Sam Harwell
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.antlr.v4.misc;

import org.antlr.v4.runtime.misc.Func1;
import org.antlr.v4.runtime.misc.IntegerList;
import org.antlr.v4.runtime.misc.Predicate;
import org.antlr.v4.tool.ast.GrammarAST;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/** */
public class Utils {
	public static final int INTEGER_POOL_MAX_VALUE = 1000;

	static Integer[] ints = new Integer[INTEGER_POOL_MAX_VALUE+1];

	/** Integer objects are immutable so share all Integers with the
	 *  same value up to some max size.  Use an array as a perfect hash.
	 *  Return shared object for 0..INTEGER_POOL_MAX_VALUE or a new
	 *  Integer object with x in it.  Java's autoboxing only caches up to 127.
	public static Integer integer(int x) {
		if ( x<0 || x>INTEGER_POOL_MAX_VALUE ) {
			return new Integer(x);
		}
		if ( ints[x]==null ) {
			ints[x] = new Integer(x);
		}
		return ints[x];
	}
	 */

    public static String stripFileExtension(String name) {
        if ( name==null ) return null;
        int lastDot = name.lastIndexOf('.');
        if ( lastDot<0 ) return name;
        return name.substring(0, lastDot);
    }

	public static String join(Object[] a, String separator) {
		StringBuilder buf = new StringBuilder();
		for (int i=0; i linesL = Arrays.asList(lines);
		StringBuilder buf = new StringBuilder();
		for (String l : linesL) {
			buf.append(l);
			buf.append('\n');
		}
		return buf.toString();
	}

	public static  List nodesToStrings(List nodes) {
		if ( nodes == null ) return null;
		List a = new ArrayList();
		for (T t : nodes) a.add(t.getText());
		return a;
	}

//	public static  List list(T... values) {
//		List x = new ArrayList(values.length);
//		for (T v : values) {
//			if ( v!=null ) x.add(v);
//		}
//		return x;
//	}

	public static String capitalize(String s) {
		return Character.toUpperCase(s.charAt(0)) + s.substring(1);
	}

	public static String decapitalize(String s) {
		return Character.toLowerCase(s.charAt(0)) + s.substring(1);
	}

	/** apply methodName to list and return list of results. method has
	 *  no args.  This pulls data out of a list essentially.
	 */
	public static  List select(List list, Func1 selector) {
		if ( list==null ) return null;
		List b = new ArrayList();
		for (From f : list) {
			b.add(selector.eval(f));
		}
		return b;
	}

	/** Find exact object type or sublass of cl in list */
	public static  T find(List ops, Class cl) {
		for (Object o : ops) {
			if ( cl.isInstance(o) ) return cl.cast(o);
//			if ( o.getClass() == cl ) return o;
		}
		return null;
	}

	public static  int indexOf(List elems, Predicate match) {
		for (int i=0; i int lastIndexOf(List elems, Predicate match) {
		for (int i=elems.size()-1; i>=0; i--) {
			if ( match.eval(elems.get(i)) ) return i;
		}
		return -1;
	}

	public static void setSize(List list, int size) {
		if (size < list.size()) {
			list.subList(size, list.size()).clear();
		} else {
			while (size > list.size()) {
				list.add(null);
			}
		}
	}

}