i have a use case where the user can send following params with get request
GET localhost/8080/users?filter=alex
OR
GET localhost/8080/users?suffixFilter=lex
OR
GET localhost/8080/users?prefixFilter=a
is it possible to add only one request param instead of 3 in controller
e.g.
instead of
#GetMapping("/users")
#ResponseBody
public String getFoos(#RequestParam String filter, #RequestParam String prefixFilter , #RequestParam String suffixFilter) {
return "ID: " + id;
}
is it possible to create a dynamic one which includes those three variantes? I was thinking creating class like this
public class FilterCreteria {
private String filter;
private String suffixFilter;
private String prefixFilter;
}
and then passing this to controller
#GetMapping("/users")
#ResponseBody
public String getFoos(#RequestParam FilterCreateria filter) {
return "ID: " + id;
}
the problem is if i send filter=alex the other attributes in the class FilterCreteria is null and i want to avoid this null.
What i searching for:
is there other way of making this possible?
if my suggestion is ok, how to avoid null attributes when the user only sends one queryparam like filter=alex?
Is there any good way to ignore some request query parameters from binding to DTO parameters?
#Data // setters and getters
class Dto {
private String param1;
private String param2;
}
#GetMapping("/hello-world")
#ResponseBody
public ResponseEntity<Dto> sayHello(Dto params)
{ ... }
I would like to exclude binding of specific param in such case.
After some research I can't find any solution for it, any help?
I have an entity class User with 20 fields, some of them being confidential fields. I have a controller class, which has a method getUser to fetch all the user from DB and send the JSON respone. Below is the sample code for the same:
#GetMapping("/getUsers")
public UserDT getUsers( Model theModel) {
List<User> userList;
userList = userService.findAll();
return userList;
}
When I run the above code, it returns all the fields from User table/User Entity Class. Instead of sending all the fields, I would like to send selected fields say Field1 to Field5 only.
Ultimate goal is to have multiple views for the same Entity Class. For URL1 I would like to show only field1 to field5 of User table, But for URL2 I would like to show Field9 , Filed15, Field20.
Do I need to create multiple Entity Class for each URL? Please guide me with the best practice to be followed in such scenario.
Assuming you are using Spring Data JPA, use projections.
So create different projections for your different URLs write a method that returns the projection (or a dynamic one as in the documentation).
public interface NamesOnlyProjection {
String getFirstName();
String getLastName();
}
public interface UserinfoProjection {
String getUsername();
String getPassword();
String getDepartment();
}
Then in your repository do something like this
public interface PersonRepository extends JpaRepository<Person, Long> {
<T> List<T> findAll(Class<T> type);
}
Then you can do something like this in your controller/service
#RestController
public class PersonController {
private final PersonRepository persons;
#GetMapping("/people/names")
public List<NamesOnlyProjection> allNames() {
return persons.findAll(NamesOnlyProjection.class);
}
#GetMapping("/people/users")
public List<UserinfoProjection> allNames() {
return persons.findAll(UserinfoProjection.class);
}
}
I would like to know how to access a deep collection class attribute in a GET request. My endpoint maps my query strings through #ModelAttribute annotation:
Given that:
public class MyEntity
{
Set<Item> items;
Integer status;
// getters setters
}
public class Item
{
String name;
// getters setters
}
And my GET request: localhost/entities/?status=0&items[0].name=Garry
Produces bellow behavior?
#RequestMapping(path = "/entities", method = RequestMethod.GET)
public List<MyEntity> findBy(#ModelAttribute MyEntity entity) {
// entity.getItems() is empty and an error is thrown: "Property referenced in indexed property path 'items[0]' is neither an array nor a List nor a Map."
}
Should my "items" be an array, List or Map? If so, there´s alternatives to keep using as Set?
Looks like there is some problem with the Set<Item>.
If you want to use Set for the items collection you have to initialize it and add some items:
e.g. like this:
public class MyEntity {
private Integer status;
private Set<Item> items;
public MyEntity() {
this.status = 0;
this.items = new HashSet<>();
this.items.add(new Item());
this.items.add(new Item());
}
//getters setters
}
but then you will be able to set only the values of this 2 items:
This will work: http://localhost:8081/map?status=1&items[0].name=asd&items[1].name=aaa
This will not work: http://localhost:8081/map?status=1&items[0].name=asd&items[1].name=aaa&items[2].name=aaa
it will say: Invalid property 'items[2]' of bean class MyEntity.
However if you switch to List:
public class MyEntity {
private Integer status;
private List<Item> items;
}
both urls map without the need to initialize anything and for various number of items.
note that I didn't use #ModelAttribute, just set the class as paramter
#GetMapping("map")//GetMapping is just a shortcut for RequestMapping
public MyEntity map(MyEntity myEntity) {
return myEntity;
}
Offtopic
Mapping a complex object in Get request sounds like a code smell to me.
Usually Get methods are used to get/read data and the url parameters are used to specify the values that should be used to filter the data that has to be read.
if you want to insert or update some data use POST, PATCH or PUT and put the complex object that you want to insert/update in the request body as JSON(you can map that in the Spring Controller with #RequestBody).
I have a database with one table named person:
id | first_name | last_name | date_of_birth
----|------------|-----------|---------------
1 | Tin | Tin | 2000-10-10
There's a JPA entity named Person that maps to this table:
#Entity
#XmlRootElement(name = "person")
#XmlAccessorType(NONE)
public class Person {
#Id
#GeneratedValue
private Long id;
#XmlAttribute(name = "id")
private Long externalId;
#XmlAttribute(name = "first-name")
private String firstName;
#XmlAttribute(name = "last-name")
private String lastName;
#XmlAttribute(name = "dob")
private String dateOfBirth;
// setters and getters
}
The entity is also annotated with JAXB annotations to allow XML payload in
HTTP requests to be mapped to instances of the entity.
I want to implement an endpoint for retrieving and updating an entity with a given id.
According to this answer to a similar question,
all I need to do is to implement the handler method as follows:
#RestController
#RequestMapping(
path = "/persons",
consumes = APPLICATION_XML_VALUE,
produces = APPLICATION_XML_VALUE
)
public class PersonController {
private final PersonRepository personRepository;
#Autowired
public PersonController(final PersonRepository personRepository) {
this.personRepository = personRepository;
}
#PutMapping(value = "/{person}")
public Person savePerson(#ModelAttribute Person person) {
return personRepository.save(person);
}
}
However this is not working as expected as can be verified by the following failing test case:
#RunWith(SpringRunner.class)
#SpringBootTest(webEnvironment = RANDOM_PORT)
public class PersonControllerTest {
#Autowired
private TestRestTemplate restTemplate;
private HttpHeaders headers;
#Before
public void before() {
headers = new HttpHeaders();
headers.setContentType(APPLICATION_XML);
}
// Test fails
#Test
#DirtiesContext
public void testSavePerson() {
final HttpEntity<Object> request = new HttpEntity<>("<person first-name=\"Tin Tin\" last-name=\"Herge\" dob=\"1907-05-22\"></person>", headers);
final ResponseEntity<Person> response = restTemplate.exchange("/persons/1", PUT, request, Person.class, "1");
assertThat(response.getStatusCode(), equalTo(OK));
final Person body = response.getBody();
assertThat(body.getFirstName(), equalTo("Tin Tin")); // Fails
assertThat(body.getLastName(), equalTo("Herge"));
assertThat(body.getDateOfBirth(), equalTo("1907-05-22"));
}
}
The first assertion fails with:
java.lang.AssertionError:
Expected: "Tin Tin"
but: was "Tin"
Expected :Tin Tin
Actual :Tin
In other words:
No server-side exceptions occur (status code is 200)
Spring successfully loads the Person instance with id=1
But its properties do not get updated
Any ideas what am I missing here?
Note 1
The solution provided here is not working.
Note 2
Full working code that demonstrates the problem is provided
here.
More Details
Expected behavior:
Load the Person instance with id=1
Populate the properties of the loaded person entity with the XML payload using Jaxb2RootElementHttpMessageConverter or MappingJackson2XmlHttpMessageConverter
Hand it to the controller's action handler as its person argument
Actual behavior:
The Person instance with id=1 is loaded
The instance's properties are not updated to match the XML in the request payload
Properties of the person instance handed to the controller's action handler method are not updated
this '#PutMapping(value = "/{person}")' brings some magic, because {person} in your case is just '1', but it happens to load it from database and put to ModelAttribute in controller. Whatever you change in test ( it can be even empty) spring will load person from database ( effectively ignoring your input ), you can stop with debugger at the very first line of controller to verify it.
You can work with it this way:
#PutMapping(value = "/{id}")
public Person savePerson(#RequestBody Person person, #PathVariable("id") Long id ) {
Person found = personRepository.findOne(id);
//merge 'found' from database with send person, or just send it with id
//Person merged..
return personRepository.save(merged);
}
wrong mapping in controller
to update entity you need to get it in persisted (managed) state first, then copy desired state on it.
consider introducing DTO for your bussiness objects, as, later, responding with persisted state entities could cause troubles (e.g. undesired lazy collections fetching or entities relations serialization to XML, JSON could cause stackoverflow due to infinite method calls)
Below is simple case of fixing your test:
#PutMapping(value = "/{id}")
public Person savePerson(#PathVariable Long id, #RequestBody Person person) {
Person persisted = personRepository.findOne(id);
if (persisted != null) {
persisted.setFirstName(person.getFirstName());
persisted.setLastName(person.getLastName());
persisted.setDateOfBirth(person.getDateOfBirth());
return persisted;
} else {
return personRepository.save(person);
}
}
Update
#PutMapping(value = "/{person}")
public Person savePerson(#ModelAttribute Person person, #RequestBody Person req) {
person.setFirstName(req.getFirstName());
person.setLastName(req.getLastName());
person.setDateOfBirth(req.getDateOfBirth());
return person;
}
The issue is that when you call personRepository.save(person) your person entity does not have the primary key field(id) and so the database ends up having two records with the new records primary key being generated by the db. The fix will be to create a setter for your id field and use it to set the entity's id before saving it:
#PutMapping(value = "/{id}")
public Person savePerson(#RequestBody Person person, #PathVariable("id") Long id) {
person.setId(id);
return personRepository.save(person);
}
Also, like has been suggested by #freakman you should use #RequestBody to capture the raw json/xml and transform it to a domain model. Also, if you don't want to create a setter for your primary key field, another option may be to support an update operation based on any other unique field (like externalId) and call that instead.
For updating any entity the load and save must be in same Transaction,else it will create new one on save() call,or will throw duplicate primary key constraint violation Exception.
To update any we need to put entity ,load()/find() and save() in same transaction, or write JPQL UPDATE query in #Repository class,and annotate that method with #Modifying .
#Modifying annotation will not fire additional select query to load entity object to update it,rather presumes that there must be a record in DB with input pk,which needs to update.