api and manager for statistic service

Change-Id: If00b8b43a2bd780ae3c05321697896290fb0f415
diff --git a/core/net/src/main/java/org/onlab/onos/net/statistic/impl/StatisticManager.java b/core/net/src/main/java/org/onlab/onos/net/statistic/impl/StatisticManager.java
new file mode 100644
index 0000000..4bca215
--- /dev/null
+++ b/core/net/src/main/java/org/onlab/onos/net/statistic/impl/StatisticManager.java
@@ -0,0 +1,89 @@
+package org.onlab.onos.net.statistic.impl;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.Path;
+import org.onlab.onos.net.flow.FlowRule;
+import org.onlab.onos.net.flow.FlowRuleEvent;
+import org.onlab.onos.net.flow.FlowRuleListener;
+import org.onlab.onos.net.flow.FlowRuleService;
+import org.onlab.onos.net.statistic.Load;
+import org.onlab.onos.net.statistic.StatisticService;
+import org.onlab.onos.net.statistic.StatisticStore;
+import org.slf4j.Logger;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Provides an implementation of the Statistic Service.
+ */
+@Component(immediate = true)
+@Service
+public class StatisticManager implements StatisticService {
+
+    private final Logger log = getLogger(getClass());
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected FlowRuleService flowRuleService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected StatisticStore statisticStore;
+
+    private final InternalFlowRuleListener listener = new InternalFlowRuleListener();
+
+    @Activate
+    public void activate() {
+        flowRuleService.addListener(listener);
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        flowRuleService.removeListener(listener);
+        log.info("Stopped");
+    }
+
+    @Override
+    public Load load(Link link) {
+        return null;
+    }
+
+    @Override
+    public Load load(ConnectPoint connectPoint) {
+        return null;
+    }
+
+    @Override
+    public Link max(Path path) {
+        return null;
+    }
+
+    @Override
+    public Link min(Path path) {
+        return null;
+    }
+
+    @Override
+    public FlowRule highestHitter(ConnectPoint connectPoint) {
+        return null;
+    }
+
+    /**
+     * Internal flow rule event listener.
+     */
+    private class InternalFlowRuleListener implements FlowRuleListener {
+
+        @Override
+        public void event(FlowRuleEvent event) {
+
+        }
+    }
+
+
+}