Refactoring the GetHostStatsCommand

- Added basic tests
  - Added test for when the key (Command) does not exist in the Map

plugins/hypervisors/xenserver/src/com/cloud/hypervisor/xenserver/resource/CitrixResourceBase.java

@@ -2250,7 +2250,7 @@ public abstract class CitrixResourceBase implements ServerResource, HypervisorRe
         }
     }
 
-    protected HostStatsEntry getHostStats(final Connection conn, final GetHostStatsCommand cmd, final String hostGuid, final long hostId) {
+    public HostStatsEntry getHostStats(final Connection conn, final GetHostStatsCommand cmd, final String hostGuid, final long hostId) {
 
         final HostStatsEntry hostStats = new HostStatsEntry(hostId, 0, 0, 0, "host", 0, 0, 0, 0);
         final Object[] rrdData = getRRDData(conn, 1); // call rrd method with 1 for host

plugins/hypervisors/xenserver/src/com/cloud/hypervisor/xenserver/resource/wrapper/CitrixRequestWrapper.java

@@ -23,6 +23,7 @@ import java.util.Hashtable;
 
 import com.cloud.agent.api.Answer;
 import com.cloud.agent.api.Command;
+import com.cloud.agent.api.GetHostStatsCommand;
 import com.cloud.agent.api.ReadyCommand;
 import com.cloud.agent.api.RebootRouterCommand;
 import com.cloud.agent.api.proxy.CheckConsoleProxyLoadCommand;
@@ -55,6 +56,7 @@ public class CitrixRequestWrapper extends RequestWrapper {
         map.put(CheckConsoleProxyLoadCommand.class, new CitrixCheckConsoleProxyLoadCommandWrapper());
         map.put(WatchConsoleProxyLoadCommand.class, new CitrixWatchConsoleProxyLoadCommandWrapper());
         map.put(ReadyCommand.class, new CitrixReadyCommandWrapper());
+        map.put(GetHostStatsCommand.class, new GetHostStatsCommandWrapper());
     }
 
     public static CitrixRequestWrapper getInstance() {
@@ -66,6 +68,10 @@ public class CitrixRequestWrapper extends RequestWrapper {
         @SuppressWarnings("unchecked")
         final CommandWrapper<Command, Answer, ServerResource> commandWrapper = map.get(command.getClass());
 
+        if (commandWrapper == null) {
+            throw new NullPointerException("No key found for '" + command.getClass() + "' in the Map!");
+        }
+
         return commandWrapper.execute(command, serverResource);
     }
 }

plugins/hypervisors/xenserver/src/com/cloud/hypervisor/xenserver/resource/wrapper/GetHostStatsCommandWrapper.java

@@ -0,0 +1,48 @@
+//
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you 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 com.cloud.hypervisor.xenserver.resource.wrapper;
+
+import org.apache.log4j.Logger;
+
+import com.cloud.agent.api.Answer;
+import com.cloud.agent.api.GetHostStatsAnswer;
+import com.cloud.agent.api.GetHostStatsCommand;
+import com.cloud.agent.api.HostStatsEntry;
+import com.cloud.hypervisor.xenserver.resource.CitrixResourceBase;
+import com.cloud.resource.CommandWrapper;
+import com.xensource.xenapi.Connection;
+
+public final class GetHostStatsCommandWrapper extends CommandWrapper<GetHostStatsCommand, Answer, CitrixResourceBase> {
+
+    private static final Logger s_logger = Logger.getLogger(GetHostStatsCommandWrapper.class);
+
+    @Override
+    public Answer execute(final GetHostStatsCommand command, final CitrixResourceBase citrixResourceBase) {
+        final Connection conn = citrixResourceBase.getConnection();
+        try {
+            final HostStatsEntry hostStats = citrixResourceBase.getHostStats(conn, command, command.getHostGuid(), command.getHostId());
+            return new GetHostStatsAnswer(command, hostStats);
+        } catch (final Exception e) {
+            final String msg = "Unable to get Host stats" + e.toString();
+            s_logger.warn(msg, e);
+            return new GetHostStatsAnswer(command, null);
+        }
+    }
+}

plugins/hypervisors/xenserver/test/com/cloud/hypervisor/xenserver/resource/wrapper/CitrixRequestWrapperTest.java

@@ -3,6 +3,7 @@ package com.cloud.hypervisor.xenserver.resource.wrapper;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -14,6 +15,8 @@ import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
 
 import com.cloud.agent.api.Answer;
+import com.cloud.agent.api.Command;
+import com.cloud.agent.api.GetHostStatsCommand;
 import com.cloud.agent.api.ReadyCommand;
 import com.cloud.agent.api.RebootAnswer;
 import com.cloud.agent.api.RebootCommand;
@@ -41,6 +44,18 @@ public class CitrixRequestWrapperTest {
         assertNotNull(wrapper);
     }
 
+    @Test
+    public void testUnknownCommand() {
+        final CitrixRequestWrapper wrapper = CitrixRequestWrapper.getInstance();
+        assertNotNull(wrapper);
+
+        try {
+            wrapper.execute(new NotAValidCommand(), citrixResourceBase);
+        } catch (final Exception e) {
+            assertTrue(e instanceof NullPointerException);
+        }
+    }
+
     @Test
     public void testExecuteRebootRouterCommand() {
         final RebootRouterCommand rebootCommand = new RebootRouterCommand("", "");
@@ -109,4 +124,25 @@ public class CitrixRequestWrapperTest {
 
         assertFalse(answer.getResult());
     }
+
+    @Test
+    public void testGetHostStatsCommandCommand() {
+        final GetHostStatsCommand statsCommand = new GetHostStatsCommand(null, null, 0);
+
+        final CitrixRequestWrapper wrapper = CitrixRequestWrapper.getInstance();
+        assertNotNull(wrapper);
+
+        final Answer answer = wrapper.execute(statsCommand, citrixResourceBase);
+
+        assertTrue(answer.getResult());
+    }
+}
+
+class NotAValidCommand extends Command {
+
+    @Override
+    public boolean executeInSequence() {
+        return false;
+    }
+
 }