Is it possible to validate a bean ensuring that at least one of three fields is not null without implementing a custom validator?
So:
public class Foo {
#NotNull(groups = {AtLeastOne.class})
private Bar b1;
#NotNull(groups = {AtLeastOne.class})
private Bar b2;
#NotNull(groups = {AtLeastOne.class})
private Bar b3;
}
But without the groups meaning that I want to validate them all in one go. I want either b1 or b2 or b3 to be not null.
Cheers,
You need annotation #Validated. example:
public class Foo {
#NotNull(groups = {AtLeastOne.class})
private Bar b1;
#NotNull(groups = {AtLeastTwo.class})
private Bar b2;
#NotNull(groups = {AtLeastThree.class})
private Bar b3;
}
#Validated(value=AtLeastOne.class) will validate only b1
#Validated(value=AtLeastTwo.class) will validate only b2
UPDATE
#NotAllNull(value={"b1", "b2", "b3"})
public class Foo {
private Bar b1;
private Bar b2;
private Bar b3;
}
#Documented
#Constraint(validatedBy = NotAllNullValidator.class)
#Target( { ElementType.TYPE })
#Retention(RetentionPolicy.RUNTIME)
public #interface NotAllNull {
String[] value;
}
public class NotAllNullValidator implements ConstraintValidator<NotAllNull, Object> {
private String[] fields;
#Override
public void initialize(final NotAllNull constraintAnnotation) {
fields = constraintAnnotation.value();
}
#Override
public boolean isValid(final Object instance, final ConstraintValidatorContext context) {
boolean result = false;
for(int i = 0 ; i < fields.length; i++) {
result |= org.apache.commons.beanutils.BeanUtils.getProperty(instance, fields[i])!=null;
}
return result;
}
}
I don't have IDE here, there may some error in the code, but hope you can see the idea behind code
take a look at #Valid and #Validated annotations on you class
Related
I know that I can map an object to a body by passing a class to bodyToMono(), like this
WebClient.RequestHeadersSpec<?> headersSpec =
bodySpec.body(Mono.just(myRequest), MyRequest.class);
MyResponse test = headersSpec.exchangeToMono(s -> {
if (s.statusCode().equals(HttpStatus.OK)) {
return s.bodyToMono(MyResponse.class);
} else {
return s.createException().flatMap(Mono::error);
}
}).block();
But for it to work I need a no-arg constructor and setters and I don't want setters, but only getters.
My question:
is there any way to make an object from a response by passing a constructor
something like this
return s.bodyToMono(new MyResponse(val1, val2, val3));
Just found out that it is possible if you add
#JsonProperty("property_name") to your constructor parameters
Update
So let's say I have this code excerpt
MyDto myDto = headersSpec.exchangeToMono(s -> {
if (s.statusCode().equals(HttpStatus.OK)) {
return s.bodyToMono(MyDto.class);
}
<...>
})
MyDto.java looks like this
public class MyDto implements Serializable {
private final String val1;
private final Val2 val2;
private final boolean val3;
private final Integer val4;
public MyDto(#JsonProperty("val1") String val1,
#JsonProperty("val2") val12 val2,
#JsonProperty("val3") boolean val3,
#JsonProperty("val4") Integer val4) {
this.val1 = val1;
this.val2 = val2;
this.val3 = val3;
this.val4 = val4;
}
<...getters...>
<... no setters...>
}
So, i.e., val1 from a response is mapped to a val1 (in constructor) by adding a #JsonProperty("val1") next to a val1
I'm trying to get the id of the last inserted object into a database using Room with Android. I can fetch the last object using an SQL query and can call other methods to get the various properties of that object which the user has set when saving the object. But getId() always returns 0. When I examine the table contents in Android Studio's app inspector, I can clearly see that Room is generating a unique primary key for each row, but I just can't get at it. Can anyone suggest what the problem might be?
Here's the Dao query:
#Query("SELECT * FROM gamebooks_table WHERE gamebookId=gamebookId ORDER BY gamebookId DESC LIMIT 1")
LiveData<Gamebook> getSingleGamebookByID();
And here's the annotated entity class:
#Entity(tableName = "gamebooks_table")
public class Gamebook {
#PrimaryKey(autoGenerate = true)
private long gamebookId;
private String gamebookName;
private String gamebookComment;
private String gamebookPublisher;
private float gamebookStarRating;
public Gamebook(String gamebookName, String gamebookComment, String gamebookPublisher, float gamebookStarRating) {
this.gamebookName = gamebookName;
this.gamebookComment = gamebookComment;
this.gamebookPublisher = gamebookPublisher;
this.gamebookStarRating = gamebookStarRating;
}
public long getGamebookId() {
return gamebookId;
}
public String getGamebookName() {
return gamebookName;
}
public String getGamebookComment() {
return gamebookComment;
}
public String getGamebookPublisher() {
return gamebookPublisher;
}
public float getGamebookStarRating(){
return gamebookStarRating;
}
public void setGamebookId(long gamebookId) {
this.gamebookId = gamebookId;
}
}
SOLVED
Finally sorted this by adding an Observer to my DAO method which returns a single gamebook. Within the Observer's onChanged() method, I can loop through all Gamebooks in the LiveData List (even though there's only one because I'm limiting it to one in the SQL query) and call getId() to get their respective IDs.
mainViewModel.getSingleGamebook().observe(this, new Observer<List<Gamebook>>() {
#Override
public void onChanged(List<Gamebook> gamebooks) {
int i=0;
for(Gamebook gamebook : gamebooks){
gamebookId= gamebook.getGamebookId();
Log.d(TAG, "Gamebook Name: "+gamebook.getGamebookName()+ " Database ID: " +gamebookId);
i++;
}
}
});
I believe that your issue is due to the only constructor being available not setting the id so the LiveData uses the default value of 0 for a long.
I'd suggest having a default constructor and thus all setters/getters and (optionally) using #Ignore annotation for one of the constructors..
without #Ignore you get warnings Gamebook.java:8: warning: There are multiple good constructors and Room will pick the no-arg constructor. You can use the #Ignore annotation to eliminate unwanted constructors. public class Gamebook {
e.g. :-
#Entity(tableName = "gamebooks_table")
public class Gamebook {
#PrimaryKey(autoGenerate = true)
private long gamebookId;
private String gamebookName;
private String gamebookComment;
private String gamebookPublisher;
private float gamebookStarRating;
public Gamebook(){} /*<<<<< ADDED */
#Ignore /*<<<<< ADDED - is not required - could be on the default constructor but not both*/
public Gamebook(String gamebookName, String gamebookComment, String gamebookPublisher, float gamebookStarRating) {
this.gamebookName = gamebookName;
this.gamebookComment = gamebookComment;
this.gamebookPublisher = gamebookPublisher;
this.gamebookStarRating = gamebookStarRating;
}
public long getGamebookId() {
return gamebookId;
}
public String getGamebookName() {
return gamebookName;
}
public String getGamebookComment() {
return gamebookComment;
}
public String getGamebookPublisher() {
return gamebookPublisher;
}
public float getGamebookStarRating(){
return gamebookStarRating;
}
public void setGamebookId(long gamebookId) {
this.gamebookId = gamebookId;
}
/* ADDED setters */
public void setGamebookName(String gamebookName) {
this.gamebookName = gamebookName;
}
public void setGamebookComment(String gamebookComment) {
this.gamebookComment = gamebookComment;
}
public void setGamebookPublisher(String gamebookPublisher) {
this.gamebookPublisher = gamebookPublisher;
}
public void setGamebookStarRating(float gamebookStarRating) {
this.gamebookStarRating = gamebookStarRating;
}
}
You also probably want to be able to pass the respective id to the getSingleGamebookByID, so you may wish to change this to:-
#Query("SELECT * FROM gamebooks_table WHERE gamebookId=:gamebookId /*<<<<< ADDED to use id passed */ ORDER BY gamebookId DESC LIMIT 1")
LiveData<Gamebook> getSingleGamebookByID(long gamebookId /*<<<<< ADDED to use id passed */);
you would probably want to remove the comments.
Note the LiveData aspect has not been tested and is conjecture.
Example
This example shows that room is fine with your original code but that the issues is on the LiveData/Viewmodel side :-
public class MainActivity extends AppCompatActivity {
TheDatabase db;
GamebookDao dao;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/* Note The Database has .allowMainThreadQueries */
db = TheDatabase.getInstance(this);
dao = db.getGamebookDao();
long gb1id = dao.insert(new Gamebook("Gamebook1","blah","Gamebook1 Publisher", 10.1F));
long gb2id = dao.insert(new Gamebook("Gamebook2","blah","Gamebook2 Publisher", 6.1F));
long gb3id = dao.insert(new Gamebook("Gamebook3","blah","Gamebook3 Publisher", 10.1F));
logGameBook(dao.getSingleGamebookByID());
logGameBook(dao.getSingleGamebookByID());
logGameBook(dao.getSingleGamebookByID());
/* Alternative that allows the ID to be specified */
logGameBook(dao.getSingleGamebookByIDAlternative(gb1id));
logGameBook(dao.getSingleGamebookByIDAlternative(gb2id));
logGameBook(dao.getSingleGamebookByIDAlternative(gb3id));
}
void logGameBook(Gamebook gb) {
Log.d("GAMEBOOKINFO","Gamebook is " + gb.getGamebookName() + " id is " + gb.getGamebookId());
}
}
The above uses your original code, the TheDatabase is a basic #Database annotated class BUT with .allowMainThreadQueries so it is run on the main thread.
The log, after running, includes:-
2022-03-12 08:16:12.556 D/GAMEBOOKINFO: Gamebook is Gamebook3 id is 3
2022-03-12 08:16:12.558 I/chatty: uid=10132(a.a.so71429144javaroomidreturnedaszero) identical 1 line
2022-03-12 08:16:12.561 D/GAMEBOOKINFO: Gamebook is Gamebook3 id is 3
2022-03-12 08:16:12.568 D/GAMEBOOKINFO: Gamebook is Gamebook1 id is 1
2022-03-12 08:16:12.572 D/GAMEBOOKINFO: Gamebook is Gamebook2 id is 2
2022-03-12 08:16:12.574 D/GAMEBOOKINFO: Gamebook is Gamebook3 id is 3
Note how the first just returns the same object and thus id.
Supposing I have the following classes:
public class A {
private String id;
private List<B> related;
}
public class B {
private String id;
private String name;
}
public class ADTO {
private String id;
private List<BDTO> relations;
}
public class BDTO {
private String identificator;
private String relatedName;
}
How can I create a mapper that given an A object type returns me an ADTO object with all the information? I have to create two different mappers? Can it be done in only one mapper? I think it would be something like the following, but I don't know how to map the atributtes from the list:
#Mapper
public interface MyMapper {
#Mappings({ #Mapping(source = "related", target = "relations") })
ADTO mapperA(A obj);
}
Thanks in advance.
try this (not tested but should work properly)
when you mapping lists you should make a map for both the class element and the list to map all the elements of the list)
#Mapper
public interface MyMapper {
#Mappings({ #Mapping(source = "related", target = "relations") })
ADTO mapperA(A obj);
#Mappings(
{ #Mapping(source = "id", target = "identificator") },
{ #Mapping(source = "name", target = "relatedName") })
BDTO bDTOMapping(B b);
List<BDTO> bDTOListMapping(List<B> bList);
}
I have two methods (in a Spring boot application) that handle an entity. The entity has two fields, both boolean isDefault and isPdfGenerated. The first method (which is called from a controller) changes the isDefault flag when a new entity is created while the second one (called from a #Scheduled annotated method) changes the isPdfGenrated after it generates a pdf file for that entity.
My problem is that sometimes the second method finds entities with the isPdfGenerated flag set to false even though the file has been generated and saved in the database.
Both the methods have the #Transactional annotation and the repository interface for the entity extends JpARepository.
My guess is that the first method loads the entity from the database before the second method does but saves the entity after the second method does its job, thus overriding the isPdfGenerated flag.
Is this possible ? If the answer is yes, how should one handle such cases ? Shouldn't JPARepository handle the case when an entity gets updated from an external source ?
Bellow is some code to better illustrate the situation.
MyController:
#Controller
#RequestMapping("/customers")
public class MyController {
#Autowired
private EntityService entityService;
#RequestMapping(value = "/{id}/changeDefault", method = RequestMethod.POST)
public String changeDefault(#PathVariable("id") Long customerId, #ModelAttribute EntityForm entityForm, Model model) {
Entity newDefaultEntity = entityService.updateDefaultEntity(customerId, entityForm);
if (newDefaultEntity == null)
return "redirect:/customers/" + customerId;
return "redirect:/customers/" + customerId + "/entity/default;
}
}
EntityService:
import org.springframework.transaction.annotation.Transactional;
#Service
public class EntityService {
#Autowired
private EntityRepository entityRepository;
#Autowired
private CustomerRepository customerRepository;
#Transactional
public Entity updateDefaultEntity(Long customerId, submittedData) {
Customer customer = customerRepository.findById(customerId);
if(customer == null)
return customer; // I know there are better ways to do this
Entity currentDefaultEntity = entityRepository.findUniqueByCustomerAndDefaultFlag(customer, true);
if(currentDefaultEntity == null)
return null; // I know there are better ways to do this also
Entity newDefaultEntity = new Entity();
newDefaultEntity.setField1(submittedData.getField1());
newDefaultEntity.setField2(submittedData.getField2());
newDefaultEntity.setCustomer(customer);
oldDefaultEntity.setDefaultFlag(false);
newDefaultEntity.setDefaultFlag(true);
entityRepository.save(newDefaultEntity);
}
#Transactional
public void generatePdfDocument(Entity entity) {
Document pdfDocument = generateDocument(entity);
if(pdfDocument == null)
return;
documentRepository.save(pdfDocument);
entity.setPdfGeneratedFlag(true);
entityRepository.save(entity);
}
}
ScheduledTasks:
#Component
public class ScheduledTasks {
private static final int SECOND_IN_MILLISECONDS = 1000;
private static final int MINUTE_IN_SECONDS = 60;
#Autowired
private EntityRepository entityRepository;
#Autowired
private DocumentService documentService;
#Scheduled(fixedDelay = 20 * SECOND_IN_MILLISECONDS)
#Transactional
public void generateDocuments() {
List<Quotation> quotationList = entityRepository.findByPdfGeneratedFlag(false);
for(Entity entity : entitiesList) {
documentService.generatePdfDocument(entity);
}
}
}
DocumentService:
#Service
public class DocumentService {
#Autowired
private EntityRepository entityRepository;
#Autowired
private DocumentRepository documentRepository;
#Transactional
public void generatePdfDocument(Entity entity) {
Document pdfDocument = generateDocument(entity);
if(pdfDocument == null)
return;
documentRepository.save(pdfDocument);
entity.setPdfGeneratedFlag(true);
entityRepository.save(entity);
}
}
EntityRepository:
#Repository
public interface EntityRepository extends JpaRepository<Entity, Long> {
Entity findById(#Param("id") Long id);
List<Entity> findByPdfGeneratedFlag(#Param("is_pdf_generated") Boolean pdfGeneratedFlag);
Entity findUniqueByCustomerAndDefaultFlag(
#Param("customer") Customer customer,
#Param("defaultFlag") Boolean defaultFlag
);
}
DocumentRepository:
#Repository
public interface DocumentRepository extends JpaRepository<Document, Long> {
Document findById(#Param("id") Long id);
}
Entity:
#Entity
#Table(name = "entities")
#JsonIdentityInfo(generator = ObjectIdGenerators.IntSequenceGenerator.class, property = "id")
public class Entity {
private Long id;
private boolean defaultFlag;
private boolean pdfGeneratedFlag;
private String field1;
private String field2;
private Customer customer;
public Entity() { }
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
#Column(name = "is_default")
public boolean isDefaultFlag() {
return defaultFlag;
}
public void setDefaultFlag(boolean defaultFlag) {
this.defaultFlag = defaultFlag;
}
#Column(name = "is_pdf_generated")
public boolean isPdfGeneratedFlag() {
return pdfGeneratedFlag;
}
public void setPdfGeneratedFlag(boolean pdfGeneratedFlag) {
this.pdfGeneratedFlag = pdfGeneratedFlag;
}
#Column(name = "field_1")
public String getField1() {
return field1;
}
public void setField1(String field1) {
this.field1 = field1;
}
#Column(name = "field_2")
public String getField2() {
return field2;
}
public void setField2(String field2) {
this.field2 = field2;
}
#ManyToOne
#JoinColumn(name = "customer_id", referencedColumnName = "id", nullable = false)
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Entity quotation = (Entity) o;
return id != null ? id.equals(entity.id) : entity.id == null;
}
#Override
public int hashCode() {
return id != null ? id.hashCode() : 0;
}
#Override
public String toString() {
return "Entity{" +
"id=" + id +
", pdfGeneratedFlag=" + pdfGeneratedFlag +
", defaultFlag=" + defaultFlag +
", field1=" + field1 +
", field2=" + field2 +
", customer=" + (customer == null ? null : customer.getId()) +
"}";
}
}
I have omitted the other classes because they are either POJOs ( EntityForm ) or the same as other domain model classes ( Document ).
If you're talking about a row on the database that is getting updated by another process after the first process has read it but before it has been updated, then you need to put in some sort of optimistic locking strategy.
This will be handled by the underlying ORM api (e.g. Hibernate or Eclipselink) rather than Spring Data (which will just handle an optimistic locking errors thrown by the ORM).
Have a look at this article. Bear in mind that if you want optimistic locking you need some way of determining a row's version. In JPA this is normally done using a column annotated with the #Version tag.
https://vladmihalcea.com/hibernate-locking-patterns-how-does-optimistic-lock-mode-work/
I have BeanItemContainer, which i load from database via jdbc:
BeanItemContainer myBeans = new BeanItemContainer<>(MyBean.class, mybeanDao.findAll());
and this is how i attach it to combobox:
Combobox combo = new Combobox();
combobox.setContainerDataSource(myBeans);
So far, so good. I received what i want, but for now i have a problem -
How do i get actual id that has been selected? This must be synchronized (id selected in combobox is actual entry in database).
I have no idea, how to solve this problem
Please help
P.S MyBean class
public class MyBean {
private Long id;
private String field1;
*** getters /setters ***
and toString() {} method
}
Here is the code:
#Theme("mytheme")
public class MyUI extends UI {
#Override
protected void init(VaadinRequest vaadinRequest) {
final VerticalLayout layout = new VerticalLayout();
layout.setMargin(true);
layout.setSpacing(true);
setContent(layout);
BeanItemContainer myBeans = new BeanItemContainer<>(MyBean.class, getBeans());
ComboBox combo = new ComboBox();
combo.setContainerDataSource(myBeans);
combo.setItemCaptionMode(AbstractSelect.ItemCaptionMode.PROPERTY);
combo.setItemCaptionPropertyId("field");
combo.addValueChangeListener(new Property.ValueChangeListener() {
#Override
public void valueChange(Property.ValueChangeEvent event) {
MyBean bean = (MyBean) combo.getValue();
Notification notif = new Notification("Selected Bean Id: "+bean.getId(), Notification.Type.TRAY_NOTIFICATION);
notif.setPosition(Position.TOP_CENTER);
notif.show(Page.getCurrent());
}
});
layout.addComponent(combo);
}
#WebServlet(urlPatterns = "/*", name = "MyUIServlet", asyncSupported = true)
#VaadinServletConfiguration(ui = MyUI.class, productionMode = false)
public static class MyUIServlet extends VaadinServlet {
}
public class MyBean {
private Long id;
private String field;
public MyBean(Long id, String field) {
this.id = id;
this.field = field;
}
public Long getId() {
return id;
}
public String getField() {
return field;
}
}
public ArrayList<MyBean> getBeans() {
ArrayList<MyBean> beans = new ArrayList<>();
MyBean bean = new MyBean(1l, "Vikrant");
beans.add(bean);
bean = new MyBean(2l, "Rampal");
beans.add(bean);
bean = new MyBean(3l, "viky");
beans.add(bean);
return beans;
}
}
If I understood the question correctly combo.getValue() should give you the MyBean instance relative to the current selection (or null if no item is selected)