Use stringUtils to check if search text is not null and is not empty

application/src/test/java/org/thingsboard/server/controller/UserControllerTest.java

@@ -1109,13 +1109,14 @@ public class UserControllerTest extends AbstractControllerTest {
 
     private List<UserEmailInfo> getUsersInfo(PageLink pageLink) throws Exception {
         List<UserEmailInfo> loadedCustomerUsers = new ArrayList<>();
-        PageData<UserEmailInfo> pageData = null;
+        PageData<UserEmailInfo> pageData;
         do {
             pageData = doGetTypedWithPageLink("/api/users/info?", new TypeReference<>() {
             }, pageLink);
             loadedCustomerUsers.addAll(pageData.getData());
             if (pageData.hasNext()) {
                 pageLink = pageLink.nextPageLink();
+                Assert.assertEquals(pageLink.getPageSize(), pageData.getData().size());
             }
         } while (pageData.hasNext());
         return loadedCustomerUsers;

dao/src/main/java/org/thingsboard/server/dao/entity/BaseEntityService.java

@@ -86,7 +86,7 @@ public class BaseEntityService extends AbstractEntityService implements EntitySe
         validateId(customerId, INCORRECT_CUSTOMER_ID + customerId);
         validateEntityDataQuery(query);
 
-        if (EntityFilterType.RELATIONS_QUERY.equals(query.getEntityFilter().getType()) || query.getPageLink().getTextSearch() != null) {
+        if (EntityFilterType.RELATIONS_QUERY.equals(query.getEntityFilter().getType()) || StringUtils.isNotEmpty(query.getPageLink().getTextSearch())) {
             return this.entityQueryDao.findEntityDataByQuery(tenantId, customerId, query);
         }