/*
 * 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.atn;

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

Utility class to create AtomTransition, RangeTransition, and SetTransition appropriately based on the range of the input. To keep the serialized ATN size small, we only inline atom and range transitions for Unicode code points <= U+FFFF. Whenever we encounter a Unicode code point > U+FFFF, we represent that as a set transition (even if it is logically an atom or a range). /**
 * Utility class to create {@link AtomTransition}, {@link RangeTransition},
 * and {@link SetTransition} appropriately based on the range of the input.
 *
 * To keep the serialized ATN size small, we only inline atom and
 * range transitions for Unicode code points <= U+FFFF.
 *
 * Whenever we encounter a Unicode code point > U+FFFF, we represent that
 * as a set transition (even if it is logically an atom or a range).
 */
public abstract class CodePointTransitions {
	
If codePoint is <= U+FFFF, returns a new AtomTransition. Otherwise, returns a new SetTransition. /**
	 * If {@code codePoint} is <= U+FFFF, returns a new {@link AtomTransition}.
	 * Otherwise, returns a new {@link SetTransition}.
	 */
	public static Transition createWithCodePoint(ATNState target, int codePoint) {
		if (Character.isSupplementaryCodePoint(codePoint)) {
			return new SetTransition(target, IntervalSet.of(codePoint));
		}
		else {
			return new AtomTransition(target, codePoint);
		}
	}

	
If codePointFrom and codePointTo are both <= U+FFFF, returns a new RangeTransition. Otherwise, returns a new SetTransition. /**
	 * If {@code codePointFrom} and {@code codePointTo} are both
	 * <= U+FFFF, returns a new {@link RangeTransition}.
	 * Otherwise, returns a new {@link SetTransition}.
	 */
	public static Transition createWithCodePointRange(
			ATNState target,
			int codePointFrom,
			int codePointTo) {
		if (Character.isSupplementaryCodePoint(codePointFrom) ||
		    Character.isSupplementaryCodePoint(codePointTo)) {
			return new SetTransition(target, IntervalSet.of(codePointFrom, codePointTo));
		}
		else {
			return new RangeTransition(target, codePointFrom, codePointTo);
		}
	}
}