Slice out MetricsHelper/Util
Change-Id: Ic6848f47d38550b78ebd6cdcf414305e54408882
diff --git a/core/api/src/main/java/org/onlab/onos/core/MetricsHelper.java b/core/api/src/main/java/org/onlab/onos/core/MetricsHelper.java
new file mode 100644
index 0000000..7c9a715
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/core/MetricsHelper.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2014 Open Networking Laboratory
+ *
+ * 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 org.onlab.onos.core;
+
+import org.onlab.metrics.MetricsComponent;
+import org.onlab.metrics.MetricsFeature;
+import org.onlab.metrics.MetricsService;
+
+import com.codahale.metrics.Timer;
+
+/**
+ * Collection of utility methods used for providing Metrics.
+ */
+public interface MetricsHelper {
+
+ /**
+ * Returns MetricService instance.
+ *
+ * @return MetricService instance
+ */
+ abstract MetricsService metricsService();
+
+
+ /**
+ * Creates a Timer instance with given name.
+ *
+ * @param component component name
+ * @param feature feature name
+ * @param name timer name
+ * @return Timer instance
+ */
+ default Timer createTimer(String component, String feature, String name) {
+ final MetricsService metricsService = metricsService();
+ if (metricsService != null) {
+ MetricsComponent c = metricsService.registerComponent(component);
+ MetricsFeature f = c.registerFeature(feature);
+ return metricsService.createTimer(c, f, name);
+ }
+ return null;
+ }
+
+}