Adding class & method comments, constants to 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

@@ -28,60 +28,219 @@ import org.wso2.carbon.device.mgt.common.PaginationResult;
 import java.util.List;
 
 /**
- * To be updated...
+ * This interface exposes useful service layer functions to retrieve data
+ * required by high level dashboard APIs.
  */
 public interface GadgetDataService {
 
+    /**
+     * This method is used to get a count of devices based on a defined filter set.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return An object of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     DeviceCountByGroupEntry getDeviceCount(FilterSet filterSet)
                             throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get a count of devices non-compliant upon on a particular feature
+     * and a defined filter set.
+     * @param nonCompliantFeatureCode Code name of the non-compliant feature.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return An object of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     DeviceCountByGroupEntry getFeatureNonCompliantDeviceCount(String nonCompliantFeatureCode,
                             FilterSet filterSet) throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get total count of devices currently enrolled under a particular tenant.
+     * @return An object of type DeviceCountByGroupEntry.
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     DeviceCountByGroupEntry getTotalDeviceCount() throws DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts classified by connectivity statuses.
+     * @return A list of objects of type DeviceCountByGroupEntry.
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getDeviceCountsByConnectivityStatuses() throws DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts classified by potential vulnerabilities.
+     * @return A list of objects of type DeviceCountByGroupEntry.
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getDeviceCountsByPotentialVulnerabilities() throws DataAccessLayerException;
 
+    /**
+     * This method is used to get non-compliant device counts classified by individual features.
+     * @param startIndex Starting index of the data set to be retrieved.
+     * @param resultCount Total count of the result set retrieved.
+     * @return An object of type PaginationResult.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     PaginationResult getNonCompliantDeviceCountsByFeatures(int startIndex, int resultCount)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts classified by platforms.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return An object of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getDeviceCountsByPlatforms(FilterSet filterSet)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts non-compliant upon a particular feature classified by platforms.
+     * @param nonCompliantFeatureCode Code name of the non-compliant feature.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return A list of objects of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getFeatureNonCompliantDeviceCountsByPlatforms(String nonCompliantFeatureCode,
                                   FilterSet filterSet) throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts classified by ownership types.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return A list of objects of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getDeviceCountsByOwnershipTypes(FilterSet filterSet)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get device counts non-compliant upon a particular feature classified by ownership types.
+     * @param nonCompliantFeatureCode Code name of the non-compliant feature.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return A list of objects of type DeviceCountByGroupEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DeviceCountByGroupEntry> getFeatureNonCompliantDeviceCountsByOwnershipTypes(String nonCompliantFeatureCode,
                                   FilterSet filterSet) throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get a paginated list of devices with details, based on a defined filter set.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @param startIndex Starting index of the data set to be retrieved.
+     * @param resultCount Total count of the result set retrieved.
+     * @return An object of type PaginationResult.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     PaginationResult getDevicesWithDetails(FilterSet filterSet, int startIndex, int resultCount)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get a paginated list of non-compliant devices with details, upon a particular feature.
+     * @param nonCompliantFeatureCode Code name of the non-compliant feature.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @param startIndex Starting index of the data set to be retrieved.
+     * @param resultCount Total count of the result set retrieved.
+     * @return An object of type PaginationResult.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     PaginationResult getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
                                                    FilterSet filterSet, int startIndex, int resultCount)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get a list of devices with details, based on a defined filter set.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return A list of objects of type DetailedDeviceEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DetailedDeviceEntry> getDevicesWithDetails(FilterSet filterSet)
                                                        throws InvalidParameterValueException, DataAccessLayerException;
 
+    /**
+     * This method is used to get a list of non-compliant devices with details, upon a particular feature.
+     * @param nonCompliantFeatureCode Code name of the non-compliant feature.
+     * @param filterSet An abstract representation of possible filtering options.
+     *                  if this value is simply "null" or no values are set for the defined filtering options,
+     *                  this method would return total device count in the system
+     *                  wrapped with in the defined return format.
+     * @return A list of objects of type DetailedDeviceEntry.
+     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
+     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
+     * @throws DataAccessLayerException This can occur due to errors connecting to database,
+     *                                  executing SQL query and retrieving data.
+     */
     @SuppressWarnings("unused")
     List<DetailedDeviceEntry> getFeatureNonCompliantDevicesWithDetails(String nonCompliantFeatureCode,
                                   FilterSet filterSet) throws InvalidParameterValueException, DataAccessLayerException;

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

@@ -29,18 +29,6 @@ import java.util.List;
 
 public interface GadgetDataServiceDAO {
 
-    /**
-     * This method is used to get device count based on a defined filter set.
-     * @param filterSet An abstract representation of possible filtering options.
-     *                  if this value is simply "null" or no values are set for the defined filtering options,
-     *                  this method would return total device count in the system
-     *                  wrapped with in the defined return format.
-     * @return An object of type DeviceCountByGroupEntry.
-     * @throws InvalidParameterValueException This can occur if and only if potentialVulnerability value of filterSet
-     *                                        is set with some value other than "NON_COMPLIANT" or "UNMONITORED".
-     * @throws DataAccessLayerException This can occur due to errors connecting to database,
-     *                                  executing SQL query and retrieving data.
-     */
     DeviceCountByGroupEntry getDeviceCount(FilterSet filterSet)
                                            throws InvalidParameterValueException, DataAccessLayerException;
 

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

@@ -31,6 +31,18 @@ public final class GadgetDataServiceDAOConstants {
 
     }
 
+    public static class Pagination {
+
+        // Minimum acceptable values for start index and result count
+        public static final int MIN_START_INDEX = 0;
+        public static final int MIN_RESULT_COUNT = 5;
+
+        private Pagination() {
+            throw new AssertionError();
+        }
+
+    }
+
     public static class PotentialVulnerability {
 
         // These constants do not hold actual database values

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

@@ -43,12 +43,14 @@ public class GenericGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDA
     public PaginationResult getNonCompliantDeviceCountsByFeatures(int startIndex, int resultCount)
                                                      throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Connection con;
@@ -108,12 +110,14 @@ public class GenericGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDA
     public PaginationResult getDevicesWithDetails(FilterSet filterSet, int startIndex, int resultCount)
                                                   throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);
@@ -204,12 +208,14 @@ public class GenericGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDA
             throw new InvalidParameterValueException("Non-compliant feature code should not be either null or empty.");
         }
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);

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

@@ -43,12 +43,14 @@ public class MSSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
     public PaginationResult getNonCompliantDeviceCountsByFeatures(int startIndex, int resultCount)
                                                      throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Connection con;
@@ -108,12 +110,14 @@ public class MSSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
     public PaginationResult getDevicesWithDetails(FilterSet filterSet, int startIndex, int resultCount)
                                                   throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);
@@ -204,12 +208,14 @@ public class MSSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
             throw new InvalidParameterValueException("Non-compliant feature code should not be either null or empty.");
         }
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);

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

@@ -43,12 +43,14 @@ public class OracleGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
     public PaginationResult getNonCompliantDeviceCountsByFeatures(int startIndex, int resultCount)
                                                      throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Connection con;
@@ -110,12 +112,14 @@ public class OracleGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
     public PaginationResult getDevicesWithDetails(FilterSet filterSet, int startIndex, int resultCount)
                                                   throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);
@@ -208,12 +212,14 @@ public class OracleGadgetDataServiceDAOImpl extends AbstractGadgetDataServiceDAO
             throw new InvalidParameterValueException("Non-compliant feature code should not be either null or empty.");
         }
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);

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

@@ -43,12 +43,14 @@ public class PostgreSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServic
     public PaginationResult getNonCompliantDeviceCountsByFeatures(int startIndex, int resultCount)
                                                       throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Connection con;
@@ -109,12 +111,14 @@ public class PostgreSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServic
     public PaginationResult getDevicesWithDetails(FilterSet filterSet, int startIndex, int resultCount)
                                                   throws InvalidParameterValueException, DataAccessLayerException {
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);
@@ -206,12 +210,14 @@ public class PostgreSQLGadgetDataServiceDAOImpl extends AbstractGadgetDataServic
             throw new InvalidParameterValueException("Non-compliant feature code should not be either null or empty.");
         }
 
-        if (startIndex < 0) {
+        if (startIndex < GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX) {
-            throw new InvalidParameterValueException("Start index should be equal to 0 or greater than that.");
+            throw new InvalidParameterValueException("Start index should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_START_INDEX + " or greater than that.");
         }
 
-        if (resultCount < 5) {
+        if (resultCount < GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT) {
-            throw new InvalidParameterValueException("Result count should be equal to 5 or greater than that.");
+            throw new InvalidParameterValueException("Result count should be equal to " +
+                GadgetDataServiceDAOConstants.Pagination.MIN_RESULT_COUNT + " or greater than that.");
         }
 
         Map<String, Object> filters = this.extractDatabaseFiltersFromBean(filterSet);

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

@@ -31,7 +31,7 @@ import java.sql.SQLException;
 import java.util.List;
 
 /**
- * To be updated...
+ * Implementation class of GadgetDataService.
  */
 public class GadgetDataServiceImpl implements GadgetDataService {