ref[SingleCache]: move SingleCache to scheduler

net/src/main/java/com/zfoo/net/util/SingleCache.java

@@ -1,69 +0,0 @@
-/*
- * Copyright (C) 2020 The zfoo Authors
- *
- * 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.zfoo.net.util;
-
-import com.zfoo.scheduler.util.TimeUtils;
-
-import java.util.concurrent.atomic.AtomicLong;
-import java.util.function.Supplier;
-
-/**
- * 单值缓存，会隔一段时间在后台刷新一下缓存
- *
- * @author godotg
- */
-public class SingleCache<V> {
-
-    private long refreshDuration;
-
-    private Supplier<V> supplier;
-
-
-    private volatile V cache;
-
-    private AtomicLong refreshTimeAtomic;
-
-
-    /**
-     * @param refreshDuration 刷新实际那，毫秒
-     * @param supplier        缓存提供者
-     * @return 简单的缓存
-     */
-    public static <V> SingleCache<V> build(long refreshDuration, Supplier<V> supplier) {
-        var cache = new SingleCache<V>();
-        cache.refreshDuration = refreshDuration;
-        cache.supplier = supplier;
-        cache.cache = supplier.get();
-        cache.refreshTimeAtomic = new AtomicLong(TimeUtils.now() + refreshDuration);
-        return cache;
-    }
-
-
-    public V get() {
-        var now = TimeUtils.now();
-        var refreshTime = refreshTimeAtomic.get();
-        // 使用双重检测锁的方式
-        if (now > refreshTime) {
-            if (refreshTimeAtomic.compareAndSet(refreshTime, now + refreshDuration)) {
-                cache = supplier.get();
-            }
-        }
-        return cache;
-    }
-
-    public void set(V value) {
-        cache = value;
-    }
-
-}