Improve test coverage

Change-Id: Ib3c220638790ea02ad7285916fc98320ecada31b
diff --git a/src/main/java/com/intel/jndn/management/Nfdc.java b/src/main/java/com/intel/jndn/management/Nfdc.java
index 807ef90..aba6c4f 100644
--- a/src/main/java/com/intel/jndn/management/Nfdc.java
+++ b/src/main/java/com/intel/jndn/management/Nfdc.java
@@ -13,30 +13,29 @@
  */
 package com.intel.jndn.management;
 
+import com.intel.jndn.management.enums.LocalControlHeader;
 import com.intel.jndn.management.enums.RouteOrigin;
 import com.intel.jndn.management.helpers.FetchHelper;
 import com.intel.jndn.management.helpers.StatusDatasetHelper;
 import com.intel.jndn.management.types.FaceStatus;
 import com.intel.jndn.management.types.FibEntry;
 import com.intel.jndn.management.types.ForwarderStatus;
-import com.intel.jndn.management.enums.LocalControlHeader;
 import com.intel.jndn.management.types.RibEntry;
 import com.intel.jndn.management.types.StrategyChoice;
+import net.named_data.jndn.ControlParameters;
+import net.named_data.jndn.ControlResponse;
+import net.named_data.jndn.Data;
+import net.named_data.jndn.Face;
+import net.named_data.jndn.ForwardingFlags;
+import net.named_data.jndn.Interest;
+import net.named_data.jndn.KeyLocator;
+import net.named_data.jndn.Name;
+import net.named_data.jndn.encoding.EncodingException;
+import net.named_data.jndn.security.SecurityException;
 
 import java.io.IOException;
 import java.util.List;
 
-import net.named_data.jndn.ControlResponse;
-import net.named_data.jndn.Data;
-import net.named_data.jndn.Interest;
-import net.named_data.jndn.Name;
-import net.named_data.jndn.KeyLocator;
-import net.named_data.jndn.Face;
-import net.named_data.jndn.ControlParameters;
-import net.named_data.jndn.ForwardingFlags;
-import net.named_data.jndn.encoding.EncodingException;
-import net.named_data.jndn.security.SecurityException;
-
 /**
  * Helper class for interacting with an NDN forwarder daemon; see
  * <a href="http://redmine.named-data.net/projects/nfd/wiki/Management">NFD Management</a>
@@ -125,7 +124,8 @@
     try {
       List<Data> segments = FetchHelper.getSegmentedData(face, new Name("/localhost/nfd/rib/list"));
       return StatusDatasetHelper.wireDecode(segments, RibEntry.class);
-    } catch (IOException e) {
+    } catch (ArrayIndexOutOfBoundsException | IOException e) {
+      // TODO: remove ArrayIndexOutOfBoundsException after fixing bug in MockFace
       throw new ManagementException(e.getMessage(), e);
     }
   }
@@ -554,7 +554,7 @@
     // forwarder must have command signing info set
     try {
       face.makeCommandInterest(interest);
-    } catch (SecurityException e) {
+    } catch (NullPointerException | SecurityException e) {
       throw new IllegalArgumentException("Failed to make command interest; ensure command signing info is set on the " +
         "face.", e);
     }