| /* |
| * Copyright 2000-2012 JetBrains s.r.o. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.intellij.openapi.util; |
| |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| /** |
| * @author ven |
| */ |
| public class Ref<T> { |
| private T myValue; |
| |
| public Ref() { } |
| |
| public Ref(@Nullable T value) { |
| myValue = value; |
| } |
| |
| public boolean isNull() { |
| return myValue == null; |
| } |
| |
| public T get() { |
| return myValue; |
| } |
| |
| public void set(@Nullable T value) { |
| myValue = value; |
| } |
| |
| public boolean setIfNull(@Nullable T value) { |
| if (myValue == null) { |
| myValue = value; |
| return true; |
| } |
| return false; |
| } |
| |
| @NotNull |
| public static <T> Ref<T> create() { |
| return new Ref<T>(); |
| } |
| |
| public static <T> Ref<T> create(@Nullable T value) { |
| return new Ref<T>(value); |
| } |
| |
| @Override |
| public String toString() { |
| return String.valueOf(myValue); |
| } |
| } |