001/*
002 * Copyright 2010-2013 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.jetbrains.jet.utils;
018
019import org.jetbrains.annotations.NotNull;
020import org.jetbrains.annotations.Nullable;
021
022public class Nulls {
023    private static final Object NULL_VALUE = new Object();
024
025    @Nullable
026    @SuppressWarnings("unchecked")
027    public static <V> V unescape(@NotNull Object value) {
028        if (value == NULL_VALUE) return null;
029        return (V) value;
030    }
031
032    @NotNull
033    public static <V> Object escape(@Nullable V value) {
034        if (value == null) return NULL_VALUE;
035        return value;
036    }
037}