[WIP] Upgrade ONOS to karaf version 4.2.1

Change-Id: I7cd40c995bdf1c80f94b1895fb3344e32404c7fa
diff --git a/cli/src/main/java/org/onosproject/cli/MetricsListCommand.java b/cli/src/main/java/org/onosproject/cli/MetricsListCommand.java
index d1ecafa..3cd9515 100644
--- a/cli/src/main/java/org/onosproject/cli/MetricsListCommand.java
+++ b/cli/src/main/java/org/onosproject/cli/MetricsListCommand.java
@@ -29,8 +29,9 @@
 import com.google.common.base.Strings;
 import com.google.common.collect.Ordering;
 import com.google.common.collect.TreeMultimap;
-import org.apache.karaf.shell.commands.Argument;
-import org.apache.karaf.shell.commands.Command;
+import org.apache.karaf.shell.api.action.Argument;
+import org.apache.karaf.shell.api.action.Command;
+import org.apache.karaf.shell.api.action.lifecycle.Service;
 import org.onlab.metrics.MetricsService;
 import org.onlab.util.Tools;
 
@@ -43,6 +44,7 @@
 /**
  * Prints metrics in the system.
  */
+@Service
 @Command(scope = "onos", name = "metrics",
          description = "Prints metrics in the system")
 public class MetricsListCommand extends AbstractShellCommand {
@@ -71,7 +73,7 @@
     String metricName = null;
 
     @Override
-    protected void execute() {
+    protected void doExecute() {
         MetricsService metricsService = get(MetricsService.class);
 
         MetricFilter filter = metricName != null ? (name, metric) -> name.equals(metricName) : MetricFilter.ALL;