| /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| ~ Licensed to the Apache Software Foundation (ASF) under one |
| ~ or more contributor license agreements. See the NOTICE file |
| ~ distributed with this work for additional information |
| ~ regarding copyright ownership. The ASF licenses this file |
| ~ to you 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 org.apache.sling.graphql.helpers.lazyloading; |
| |
| import java.util.function.Supplier; |
| |
| /** Helper for a single lazy-loading value */ |
| public class LazyLoadingField<T> { |
| |
| @SuppressWarnings("squid:S3077") |
| // The Supplier itself is immutable, just "volatile" is fine |
| private volatile Supplier<T> supplier; |
| |
| private T value; |
| |
| public LazyLoadingField(Supplier<T> supplier) { |
| this.supplier = supplier; |
| } |
| |
| public T get() { |
| if(supplier != null) { |
| synchronized(this) { |
| if(supplier != null) { |
| value = supplier.get(); |
| supplier = null; |
| } |
| } |
| } |
| return value; |
| } |
| } |