| /* |
| * 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.util.keyFMap; |
| |
| import com.intellij.openapi.util.Key; |
| import org.jetbrains.annotations.NotNull; |
| |
| class EmptyFMap implements KeyFMap { |
| EmptyFMap() { |
| } |
| |
| @NotNull |
| @Override |
| public <V> KeyFMap plus(@NotNull Key<V> key, @NotNull V value) { |
| return new OneElementFMap<V>(key, value); |
| } |
| |
| @NotNull |
| @Override |
| public KeyFMap minus(@NotNull Key<?> key) { |
| return this; |
| } |
| |
| @Override |
| public <V> V get(@NotNull Key<V> key) { |
| return null; |
| } |
| |
| @Override |
| public String toString() { |
| return "<empty>"; |
| } |
| |
| @Override |
| public boolean isEmpty() { |
| return true; |
| } |
| } |