feat[cache]: async lazyGet for SingleCache

scheduler/src/main/java/com/zfoo/scheduler/manager/SchedulerBus.java

@@ -187,4 +187,11 @@ public abstract class SchedulerBus {
         registerScheduler(SchedulerDefinition.valueOf(cron, runnable));
     }
 
+    /**
+     * 立刻执行的任务
+     */
+    public static void execute(Runnable runnable) {
+        executor.execute(ThreadUtils.safeRunnable(runnable));
+    }
+
 }

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

@@ -13,6 +13,9 @@
 
 package com.zfoo.scheduler.util;
 
+import com.zfoo.scheduler.manager.SchedulerBus;
+
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.Supplier;
 
@@ -60,6 +63,18 @@ public class SingleCache<V> {
         return cache;
     }
 
+    public V lazyGet() {
+        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)) {
+                SchedulerBus.execute(() -> cache = supplier.get());
+            }
+        }
+        return cache;
+    }
+
     public void set(V value) {
         cache = value;
     }