| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // 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.google.devtools.build.lib.skyframe; |
| |
| import com.google.common.base.MoreObjects; |
| import com.google.common.base.Supplier; |
| |
| /** |
| * Supplier whose value can be changed by clients who have a reference to it as a MutableSupplier. |
| * Unlike an {@code AtomicReference}, clients who are passed a MutableSupplier as a Supplier cannot |
| * change its value without a reckless cast. |
| */ |
| public class MutableSupplier<T> implements Supplier<T> { |
| private T val; |
| |
| @Override |
| public T get() { |
| return val; |
| } |
| |
| /** |
| * Sets the value of the object supplied. Do not cast a Supplier to a MutableSupplier in order to |
| * call this method! |
| */ |
| public void set(T newVal) { |
| val = newVal; |
| } |
| |
| @Override |
| public String toString() { |
| return MoreObjects.toStringHelper(getClass()) |
| .add("val", val).toString(); |
| } |
| } |