Adding temporary development code bits for dashboard analytics feature

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/GadgetDataService.java

@@ -30,58 +30,61 @@ import java.util.Map;
 public interface GadgetDataService {
 
     @SuppressWarnings("unused")
-    int getTotalDeviceCount();
+    int getTotalDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getActiveDeviceCount();
+    int getActiveDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getInactiveDeviceCount();
+    int getInactiveDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getRemovedDeviceCount();
+    int getRemovedDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getNonCompliantDeviceCount();
+    int getNonCompliantDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getUnmonitoredDeviceCount();
+    int getUnmonitoredDeviceCount() throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest);
+    PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest)
+            throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getDeviceCount(Map<String, Object> filters);
+    int getDeviceCount(Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    int getFeatureNonCompliantDeviceCount(String nonCompliantFeatureCode, Map<String, Object> filters);
+    int getFeatureNonCompliantDeviceCount(String nonCompliantFeatureCode,
+                                          Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    Map<String, Integer> getDeviceCountsByPlatforms(Map<String, Object> filters);
+    Map<String, Integer> getDeviceCountsByPlatforms(Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
     Map<String, Integer> getFeatureNonCompliantDeviceCountsByPlatforms(String nonCompliantFeatureCode,
-                                                                       Map<String, Object> filters);
+                                                         Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    Map<String, Integer> getDeviceCountsByOwnershipTypes(Map<String, Object> filters);
+    Map<String, Integer> getDeviceCountsByOwnershipTypes(Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
     Map<String, Integer> getFeatureNonCompliantDeviceCountsByOwnershipTypes(String nonCompliantFeatureCode,
-                                                                            Map<String, Object> filters);
+                                                         Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    PaginationResult getDevicesWithDetails(Map<String, Object> filters, PaginationRequest paginationRequest);
+    PaginationResult getDevicesWithDetails(Map<String, Object> filters,
+                                           PaginationRequest paginationRequest) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
     PaginationResult getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
-                    Map<String, Object> filters, PaginationRequest paginationRequest);
+                    Map<String, Object> filters, PaginationRequest paginationRequest) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
-    List<Map<String, Object>> getDevicesWithDetails(Map<String, Object> filters);
+    List<Map<String, Object>> getDevicesWithDetails(Map<String, Object> filters) throws GadgetDataServiceException;
 
     @SuppressWarnings("unused")
     List<Map<String, Object>> getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
-                                                                       Map<String, Object> filters);
+                                                         Map<String, Object> filters) throws GadgetDataServiceException;
 
 }

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/dao/GadgetDataServiceDAOException.java

@@ -18,11 +18,11 @@
 
 package org.wso2.carbon.device.mgt.analytics.dashboard.dao;
 
-@SuppressWarnings("unused")
 /**
- * Custom exception class for data access related exceptions.
+ * Custom exception class for GadgetDataServiceDAO layer.
  */
 public class GadgetDataServiceDAOException extends Exception {
+
     private String errorMessage;
     private static final long serialVersionUID = 2021891706072918864L;
 
@@ -43,6 +43,7 @@ public class GadgetDataServiceDAOException extends Exception {
      * @param errorMessage Specific error message.
      * @param cause Cause of this exception.
      */
+    @SuppressWarnings("unused")
     public GadgetDataServiceDAOException(String errorMessage, Throwable cause) {
         super(errorMessage, cause);
         setErrorMessage(errorMessage);
@@ -53,6 +54,7 @@ public class GadgetDataServiceDAOException extends Exception {
      *
      * @param errorMessage Specific error message.
      */
+    @SuppressWarnings("unused")
     public GadgetDataServiceDAOException(String errorMessage) {
         super(errorMessage);
         setErrorMessage(errorMessage);
@@ -63,10 +65,12 @@ public class GadgetDataServiceDAOException extends Exception {
      *
      * @param cause Cause of this exception.
      */
+    @SuppressWarnings("unused")
     public GadgetDataServiceDAOException(Throwable cause) {
         super(cause);
     }
 
+    @SuppressWarnings("unused")
     public String getErrorMessage() {
         return errorMessage;
     }
@@ -74,4 +78,5 @@ public class GadgetDataServiceDAOException extends Exception {
     public void setErrorMessage(String errorMessage) {
         this.errorMessage = errorMessage;
     }
+
 }

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/dao/GadgetDataServiceDAOFactory.java

@@ -33,6 +33,7 @@ import java.util.List;
 
 @SuppressWarnings("unused")
 public class GadgetDataServiceDAOFactory {
+
     private static final Log log = LogFactory.getLog(GadgetDataServiceDAOFactory.class);
     private static DataSource dataSource;
     private static String databaseEngine;
@@ -47,7 +48,7 @@ public class GadgetDataServiceDAOFactory {
         try {
             databaseEngine = dataSource.getConnection().getMetaData().getDatabaseProductName();
         } catch (SQLException e) {
-            log.error("Error occurred while retrieving config.datasource connection", e);
+            log.error("Error occurred while retrieving config.datasource connection.", e);
         }
     }
 
@@ -56,7 +57,7 @@ public class GadgetDataServiceDAOFactory {
         try {
             databaseEngine = dataSource.getConnection().getMetaData().getDatabaseProductName();
         } catch (SQLException e) {
-            log.error("Error occurred while retrieving config.datasource connection", e);
+            log.error("Error occurred while retrieving config.datasource connection.", e);
         }
     }
 
@@ -65,7 +66,7 @@ public class GadgetDataServiceDAOFactory {
         if (conn != null) {
             throw new IllegalTransactionStateException("A transaction is already active within the context of " +
                 "this particular thread. Therefore, calling 'beginTransaction/openConnection' while another " +
-                    "transaction is already active is a sign of improper transaction handling");
+                    "transaction is already active is a sign of improper transaction handling.");
         }
         conn = dataSource.getConnection();
         currentConnection.set(conn);
@@ -76,7 +77,7 @@ public class GadgetDataServiceDAOFactory {
         if (conn == null) {
             throw new IllegalTransactionStateException("No connection is associated with the current transaction. " +
                 "This might have ideally been caused by not properly initiating the transaction via " +
-                    "'beginTransaction'/'openConnection' methods");
+                    "'beginTransaction'/'openConnection' methods.");
         }
         return conn;
     }
@@ -86,35 +87,34 @@ public class GadgetDataServiceDAOFactory {
         if (conn == null) {
             throw new IllegalTransactionStateException("No connection is associated with the current transaction. " +
                 "This might have ideally been caused by not properly initiating the transaction via " +
-                    "'beginTransaction'/'openConnection' methods");
+                "'beginTransaction'/'openConnection' methods.");
         }
         try {
             conn.close();
         } catch (SQLException e) {
-            log.warn("Error occurred while close the connection");
+            log.warn("Error occurred while close the connection.");
         }
         currentConnection.remove();
     }
 
 
     /**
-     * Resolve data source from the data source definition
+     * Resolve data source from the data source definition.
      *
-     * @param config data source configuration
+     * @param config data source configuration.
-     * @return data source resolved from the data source definition
+     * @return data source resolved from the data source definition.
      */
     private static DataSource resolveDataSource(DataSourceConfig config) {
         DataSource dataSource = null;
         if (config == null) {
             throw new RuntimeException(
                 "Device Management Repository data source configuration " + "is null and " +
-                            "thus, is not initialized");
+                    "thus, is not initialized.");
         }
         JNDILookupDefinition jndiConfig = config.getJndiLookupDefinition();
         if (jndiConfig != null) {
             if (log.isDebugEnabled()) {
-                log.debug("Initializing Device Management Repository data source using the JNDI " +
+                log.debug("Initializing Device Management Repository data source using the JNDI Lookup Definition.");
-                        "Lookup Definition");
             }
             List<JNDILookupDefinition.JNDIProperty> jndiPropertyList = jndiConfig.getJndiProperties();
             if (jndiPropertyList != null) {

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/dao/GadgetDataServiceDAOImpl.java

@@ -18,8 +18,6 @@
 
 package org.wso2.carbon.device.mgt.analytics.dashboard.dao;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.context.PrivilegedCarbonContext;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
 import org.wso2.carbon.device.mgt.common.PaginationResult;
@@ -35,8 +33,6 @@ import java.util.List;
 import java.util.Map;
 
 class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
-    @SuppressWarnings("unused")
-    private static final Log log = LogFactory.getLog(GadgetDataServiceDAOImpl.class);
 
     @Override
     public int getTotalDeviceCount() throws GadgetDataServiceDAOException {
@@ -72,7 +68,15 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
     }
 
     @Override
-    public PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest) throws GadgetDataServiceDAOException {
+    public int getUnmonitoredDeviceCount() throws GadgetDataServiceDAOException {
+        Map<String, Object> filters = new HashMap<>();
+        filters.put("POLICY_ID", -1);
+        return this.getDeviceCount(filters);
+    }
+
+    @Override
+    public PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest)
+                                                                  throws GadgetDataServiceDAOException {
         Connection con;
         PreparedStatement stmt = null;
         ResultSet rs = null;
@@ -112,7 +116,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 totalRecordsCount = rs.getInt("NON_COMPLIANT_FEATURE_COUNT");
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting non compliant device counts by features.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -122,13 +127,6 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
         return paginationResult;
     }
 
-    @Override
-    public int getUnmonitoredDeviceCount() throws GadgetDataServiceDAOException {
-        Map<String, Object> filters = new HashMap<>();
-        filters.put("POLICY_ID", -1);
-        return this.getDeviceCount(filters);
-    }
-
     public int getDeviceCount(Map<String, Object> filters) throws GadgetDataServiceDAOException {
         Connection con;
         PreparedStatement stmt = null;
@@ -166,7 +164,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCount = rs.getInt("DEVICE_COUNT");
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered device count.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -211,7 +210,9 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCount = rs.getInt("DEVICE_COUNT");
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered device count, " +
+                    "non compliant by a particular feature.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -257,7 +258,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCountsByPlatforms.put(rs.getString("PLATFORM"), rs.getInt("DEVICE_COUNT"));
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of device counts by platforms.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -304,7 +306,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCountsByPlatforms.put(rs.getString("PLATFORM"), rs.getInt("DEVICE_COUNT"));
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a set of feature non-compliant device counts by platforms.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -350,7 +353,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCountsByOwnershipTypes.put(rs.getString("OWNERSHIP"), rs.getInt("DEVICE_COUNT"));
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of device counts by ownership types.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -398,7 +402,9 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDeviceCountsByOwnershipTypes.put(rs.getString("OWNERSHIP"), rs.getInt("DEVICE_COUNT"));
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of feature " +
+                    "non-compliant device counts by ownership types.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -469,7 +475,9 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 totalRecordsCount = rs.getInt("DEVICE_COUNT");
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of devices " +
+                    "with details when pagination is enabled.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -546,7 +554,9 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 totalRecordsCount = rs.getInt("DEVICE_COUNT");
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of feature non-compliant devices " +
+                    "with details when pagination is enabled.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -600,7 +610,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDevicesWithDetails.add(filteredDeviceWithDetails);
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting a filtered set of devices with details.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }
@@ -654,7 +665,8 @@ class GadgetDataServiceDAOImpl implements GadgetDataServiceDAO {
                 filteredDevicesWithDetails.add(filteredDeviceWithDetails);
             }
         } catch (SQLException e) {
-            throw new GadgetDataServiceDAOException("Error occurred while executing a selection query to the database", e);
+            throw new GadgetDataServiceDAOException("Error occurred @ GadgetDataServiceDAO layer while trying to " +
+                "execute relevant SQL queries for getting filtered set of feature non-compliant devices with details.", e);
         } finally {
             DeviceManagementDAOUtil.cleanupResources(stmt, rs);
         }

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/internal/GadgetDataServiceComponent.java

@@ -39,6 +39,7 @@ import org.wso2.carbon.ndatasource.core.DataSourceService;
  * unbind="unsetDataSourceService"
  */
 public class GadgetDataServiceComponent {
+
     private static final Log log = LogFactory.getLog(GadgetDataServiceComponent.class);
 
     protected void activate(ComponentContext componentContext) {
@@ -56,10 +57,10 @@ public class GadgetDataServiceComponent {
             componentContext.getBundleContext().
                     registerService(GadgetDataService.class.getName(), new GadgetDataServiceImpl(), null);
             if (log.isDebugEnabled()) {
-                log.debug("Device Management Dashboard Analytics Bundle has been started successfully");
+                log.debug("Device Management Dashboard Analytics Bundle has been started successfully.");
             }
         } catch (Throwable e) {
-            log.error("Error occurred while initializing the bundle", e);
+            log.error("Error occurred while initializing the bundle.", e);
         }
     }
 
@@ -71,10 +72,17 @@ public class GadgetDataServiceComponent {
     }
 
     public void setDataSourceService(DataSourceService dataSourceService) {
-
+        if (log.isDebugEnabled()) {
+            log.debug("Binding org.wso2.carbon.ndatasource.core.DataSourceService...");
+        }
+        //do nothing
     }
 
     public void unsetDataSourceService(DataSourceService dataSourceService) {
+        if (log.isDebugEnabled()) {
+            log.debug("Unbinding org.wso2.carbon.ndatasource.core.DataSourceService...");
+        }
+        //do nothing
+    }
 
 }
-}

components/device-mgt/org.wso2.carbon.device.mgt.analytics.dashboard/src/main/java/org/wso2/carbon/device/mgt/analytics/dashboard/internal/GadgetDataServiceImpl.java

@@ -18,9 +18,8 @@
 
 package org.wso2.carbon.device.mgt.analytics.dashboard.internal;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.analytics.dashboard.GadgetDataService;
+import org.wso2.carbon.device.mgt.analytics.dashboard.GadgetDataServiceException;
 import org.wso2.carbon.device.mgt.analytics.dashboard.dao.GadgetDataServiceDAOException;
 import org.wso2.carbon.device.mgt.analytics.dashboard.dao.GadgetDataServiceDAOFactory;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
@@ -35,18 +34,18 @@ import java.util.Map;
  */
 class GadgetDataServiceImpl implements GadgetDataService {
 
-    @SuppressWarnings("unused")
-    private static final Log log = LogFactory.getLog(GadgetDataServiceImpl.class);
-
     @Override
-    public int getTotalDeviceCount() {
+    public int getTotalDeviceCount() throws GadgetDataServiceException {
         int totalDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             totalDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getTotalDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            totalDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return totalDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for total device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -54,14 +53,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getActiveDeviceCount() {
+    public int getActiveDeviceCount() throws GadgetDataServiceException {
         int activeDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             activeDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getActiveDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            activeDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return activeDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for active device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -69,14 +71,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getInactiveDeviceCount() {
+    public int getInactiveDeviceCount() throws GadgetDataServiceException {
         int inactiveDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             inactiveDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getInactiveDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            inactiveDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return inactiveDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for inactive device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -84,14 +89,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getRemovedDeviceCount() {
+    public int getRemovedDeviceCount() throws GadgetDataServiceException {
         int removedDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             removedDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getRemovedDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            removedDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return removedDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for removed device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -99,14 +107,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getNonCompliantDeviceCount() {
+    public int getNonCompliantDeviceCount() throws GadgetDataServiceException {
         int nonCompliantDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             nonCompliantDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getNonCompliantDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            nonCompliantDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return nonCompliantDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for non-compliant device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -114,14 +125,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getUnmonitoredDeviceCount() {
+    public int getUnmonitoredDeviceCount() throws GadgetDataServiceException {
         int unmonitoredDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             unmonitoredDeviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getUnmonitoredDeviceCount();
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            unmonitoredDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return unmonitoredDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for unmonitored device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -129,14 +143,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest) {
+    public PaginationResult getNonCompliantDeviceCountsByFeatures(PaginationRequest paginationRequest)
-        PaginationResult paginationResult = null;
+                                                                  throws GadgetDataServiceException {
+        PaginationResult paginationResult;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             paginationResult = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                 getNonCompliantDeviceCountsByFeatures(paginationRequest);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for non-compliant device counts by features.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -144,14 +163,17 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getDeviceCount(Map<String, Object> filters) {
+    public int getDeviceCount(Map<String, Object> filters) throws GadgetDataServiceException {
         int deviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             deviceCount = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getDeviceCount(filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            deviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return deviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in calling DAO function for getting a filtered device count.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -159,15 +181,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public int getFeatureNonCompliantDeviceCount(String nonCompliantFeatureCode, Map<String, Object> filters) {
+    public int getFeatureNonCompliantDeviceCount(String nonCompliantFeatureCode, Map<String, Object> filters)
+                                                 throws GadgetDataServiceException {
         int featureNonCompliantDeviceCount;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             featureNonCompliantDeviceCount = GadgetDataServiceDAOFactory.
                 getGadgetDataServiceDAO().getFeatureNonCompliantDeviceCount(nonCompliantFeatureCode, filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            featureNonCompliantDeviceCount = -1;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
-            return featureNonCompliantDeviceCount;
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting a filtered device count, non compliant by a particular feature.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -175,14 +201,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public Map<String, Integer> getDeviceCountsByPlatforms(Map<String, Object> filters) {
+    public Map<String, Integer> getDeviceCountsByPlatforms(Map<String, Object> filters)
-        Map<String, Integer> deviceCountsByPlatforms = null;
+                                                           throws GadgetDataServiceException {
+        Map<String, Integer> deviceCountsByPlatforms;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             deviceCountsByPlatforms = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                 getDeviceCountsByPlatforms(filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered device counts by platforms.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -191,14 +222,18 @@ class GadgetDataServiceImpl implements GadgetDataService {
 
     @Override
     public Map<String, Integer> getFeatureNonCompliantDeviceCountsByPlatforms(String nonCompliantFeatureCode,
-                                                                              Map<String, Object> filters) {
+                                                       Map<String, Object> filters) throws GadgetDataServiceException {
-        Map<String, Integer> featureNonCompliantDeviceCountsByPlatforms = null;
+        Map<String, Integer> featureNonCompliantDeviceCountsByPlatforms;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             featureNonCompliantDeviceCountsByPlatforms = GadgetDataServiceDAOFactory.
                 getGadgetDataServiceDAO().getFeatureNonCompliantDeviceCountsByPlatforms(nonCompliantFeatureCode, filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered device counts by platforms, non compliant by a particular feature.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -206,14 +241,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public Map<String, Integer> getDeviceCountsByOwnershipTypes(Map<String, Object> filters) {
+    public Map<String, Integer> getDeviceCountsByOwnershipTypes(Map<String, Object> filters)
-        Map<String, Integer> deviceCountsByOwnershipTypes = null;
+                                                                throws GadgetDataServiceException {
+        Map<String, Integer> deviceCountsByOwnershipTypes;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             deviceCountsByOwnershipTypes = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                 getDeviceCountsByOwnershipTypes(filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered device counts by ownership types.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -222,15 +262,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
 
     @Override
     public Map<String, Integer> getFeatureNonCompliantDeviceCountsByOwnershipTypes(String nonCompliantFeatureCode,
-                                                                                   Map<String, Object> filters) {
+                                                        Map<String, Object> filters) throws GadgetDataServiceException {
-        Map<String, Integer> featureNonCompliantDeviceCountsByOwnershipTypes = null;
+        Map<String, Integer> featureNonCompliantDeviceCountsByOwnershipTypes;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             featureNonCompliantDeviceCountsByOwnershipTypes =
                 GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                     getFeatureNonCompliantDeviceCountsByOwnershipTypes(nonCompliantFeatureCode, filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection.", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered device counts by ownership types, non compliant by a particular feature.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -238,14 +282,19 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public PaginationResult getDevicesWithDetails(Map<String, Object> filters, PaginationRequest paginationRequest) {
+    public PaginationResult getDevicesWithDetails(Map<String, Object> filters,
-        PaginationResult paginationResult = null;
+                        PaginationRequest paginationRequest) throws GadgetDataServiceException {
+        PaginationResult paginationResult;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             paginationResult = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                     getDevicesWithDetails(filters, paginationRequest);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered devices with details when pagination is enabled.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -254,14 +303,18 @@ class GadgetDataServiceImpl implements GadgetDataService {
 
     @Override
     public PaginationResult getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
-                            Map<String, Object> filters, PaginationRequest paginationRequest) {
+                   Map<String, Object> filters, PaginationRequest paginationRequest) throws GadgetDataServiceException {
-        PaginationResult paginationResult = null;
+        PaginationResult paginationResult;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             paginationResult = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                     getFeatureNonCompliantDevicesWithDetails(nonCompliantFeatureCode, filters, paginationRequest);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered devices with details, non compliant by feature when pagination is enabled.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -269,13 +322,18 @@ class GadgetDataServiceImpl implements GadgetDataService {
     }
 
     @Override
-    public List<Map<String, Object>> getDevicesWithDetails(Map<String, Object> filters) {
+    public List<Map<String, Object>> getDevicesWithDetails(Map<String, Object> filters)
-        List<Map<String, Object>> devicesWithDetails = null;
+                                                           throws GadgetDataServiceException {
+        List<Map<String, Object>> devicesWithDetails;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             devicesWithDetails = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().getDevicesWithDetails(filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered devices with details.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }
@@ -284,14 +342,18 @@ class GadgetDataServiceImpl implements GadgetDataService {
 
     @Override
     public List<Map<String, Object>> getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
-                                                                              Map<String, Object> filters) {
+                                                       Map<String, Object> filters) throws GadgetDataServiceException {
-        List<Map<String, Object>> featureNonCompliantDevicesWithDetails = null;
+        List<Map<String, Object>> featureNonCompliantDevicesWithDetails;
         try {
             GadgetDataServiceDAOFactory.openConnection();
             featureNonCompliantDevicesWithDetails = GadgetDataServiceDAOFactory.getGadgetDataServiceDAO().
                 getFeatureNonCompliantDevicesWithDetails(nonCompliantFeatureCode, filters);
-        } catch (GadgetDataServiceDAOException | SQLException e) {
+        } catch (SQLException e) {
-            return null;
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer " +
+                "in opening database connection", e);
+        } catch (GadgetDataServiceDAOException e) {
+            throw new GadgetDataServiceException("Error occurred @ GadgetDataService layer in calling DAO function " +
+                "for getting filtered devices with details, non compliant by feature.", e);
         } finally {
             GadgetDataServiceDAOFactory.closeConnection();
         }