add descriptive comments

components/application-mgt/org.wso2.carbon.identity.application.mgt/src/main/java/org/wso2/carbon/identity/application/mgt/ApplicationMgtUtil.java

@@ -1374,7 +1374,13 @@ public static String[] getLoggedInUserGroupIDList() throws IdentityApplicationMa
     }
 
     /**
-     * Add the current discoverable group to the list of discoverable groups.
+     * This method is used to build the discoverable groups list from the database result.
+     * Note: Group association list should be sorted by domain and provide group IDs in order.
+     * Where `discoverableGroups` list keeps the complete list of discoverable groups and
+     *  currentDomainGroups  list keeps the list of groups in the current iterating domain.
+     * The method will add the `currentDomainGroups` list to the `discoverableGroups` list
+     * if the domain name is change from the previous iteration.
+     * If the domain name is same, the group will be added to the `currentDomainGroups` list.
      *
      * @param discoverableGroups  All list of discoverable groups.
      * @param currentDomainGroups List of groups in the current iterating domain.

components/application-mgt/org.wso2.carbon.identity.application.mgt/src/main/java/org/wso2/carbon/identity/application/mgt/validator/DefaultApplicationValidator.java

@@ -206,6 +206,15 @@ private void validateDiscoverabilityConfigs(List<String> validationErrors, Servi
 
     /**
      * Validate whether the provided discoverable groups are valid.
+     * This will perform the following validations if discoverable groups are defined.
+     * 1. Check whether the application is discoverable.
+     * 2. Check whether the user store is defined for the discoverable group.
+     * 3. Check whether the user store is available.
+     * 4. Check whether groups are defined for the discoverable group.
+     * 5. Check whether group ID is defined for the group.
+     * 6. Check whether the group exists in the user store.
+     * If any of the above validations fail, the corresponding error message will be added to the validation errors
+     * list.
      *
      * @param validationErrors List of validation errors.
      * @param serviceProvider  Service provider configuration.