init metric calculate

store/src/main/java/org/apache/rocketmq/store/timer/rocksdb/TimerMessageKVStore.java

@@ -80,4 +80,11 @@ public interface TimerMessageKVStore {
      * @return the checkpoint of the timer message kv store.
      */
     long getCheckpoint(byte[] columnFamily);
+
+    /**
+     * Sync the metric of the timer message kv store.
+     * @param key the key of the metric.
+     * @param update the value of the metric.
+     */
+    void syncMetric(int key, int update);
 }

store/src/main/java/org/apache/rocketmq/store/timer/rocksdb/TimerMessageRocksDBStorage.java

@@ -259,6 +259,11 @@ public long getCheckpoint(byte[] columnFamily) {
         }
     }
 
+    @Override
+    public void syncMetric(int key, int update) {
+        // TODO sync metric
+    }
+
     private void syncCheckpoint(byte[] columnFamily, long checkpoint, WriteBatch writeBatch) {
         try {
             writeBatch.put(columnFamily, ByteBuffer.allocate(8).putLong(checkpoint).array());
@@ -274,12 +279,4 @@ private void syncCommitOffset(long offset, WriteBatch writeBatch) {
             throw new RuntimeException("Sync commit offset error", e);
         }
     }
-
-    private void syncMetric(int key, int update, WriteBatch writeBatch) {
-        try {
-            writeBatch.put(metricColumnFamilyHandle, ByteBuffer.allocate(4).putInt(key).array(), ByteBuffer.allocate(4).putInt(update).array());
-        } catch (RocksDBException e) {
-            throw new RuntimeException("Sync metric error", e);
-        }
-    }
 }