Adding comments

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/GenericApplicationDAOImpl.java

@@ -30,6 +30,9 @@ import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
 
+/**
+ * Generic DAO implementation for Application Management Operations
+ */
 public class GenericApplicationDAOImpl extends AbstractApplicationDAOImpl{
 
     @Override

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/PostgreSQLApplicationDAOImpl.java

@@ -30,6 +30,9 @@ import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
 
+/**
+ * PosgreSQL specific DAO implementation for Application Management Operations
+ */
 public class PostgreSQLApplicationDAOImpl extends AbstractApplicationDAOImpl{
 
     @Override