MSC2140 Add SQL storage for hashes and the time-based rotation policy.

src/main/java/io/kamax/mxisd/hash/rotation/TimeBasedRotation.java

@@ -0,0 +1,34 @@
+package io.kamax.mxisd.hash.rotation;
+
+import io.kamax.mxisd.hash.HashEngine;
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+public class TimeBasedRotation implements HashRotationStrategy {
+
+    private final long delay;
+    private HashEngine hashEngine;
+    private final ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
+
+    public TimeBasedRotation(long delay) {
+        this.delay = delay;
+    }
+
+    @Override
+    public void register(HashEngine hashEngine) {
+        this.hashEngine = hashEngine;
+        Runtime.getRuntime().addShutdownHook(new Thread(executorService::shutdown));
+        executorService.scheduleWithFixedDelay(this::trigger, 0, delay, TimeUnit.SECONDS);
+    }
+
+    @Override
+    public HashEngine getHashEngine() {
+        return hashEngine;
+    }
+
+    @Override
+    public void newRequest() {
+    }
+}