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Http Response parameter name incorrect using Spring Boot/Angular

I'm trying to display a table listing the Country codes (iso3166) in a postgresql db onto an html page using Spring Boot and Angular, the parameter name in the http response lists "number" when instead I want it to list "nbr".
The SQL table has 4 columns
name (varchar) unique
alpha2 (varchar) PK unique
alpha3 (varchar) unique
nbr (int4)
My Spring Boot Models is the following:
#Entity
#Table(name = "iso3166")
public class Country {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private String alpha2;
#Column(name = "name")
private String name;
#Column(name = "alpha3")
private String alpha3;
#Column(name = "nbr")
private int nbr;
public Country()
{
}
public Country(String name, String alpha2, String alpha3, int nbr)
{
this.name = name;
this.alpha2 = alpha2;
this.alpha3 = alpha3;
this.nbr = nbr;
}
/*
getters and settings + toString()
*/
The repository uses JPARepository
public interface ICountryRepository extends JpaRepository<Country, String> {
}
And the Controller has only the findAll() method
#RestController
#RequestMapping({"/api"})
public class CountryController {
#Autowired
ICountryRepository countryRepository;
#GetMapping
public List<Country> findAll(){
List<Country> country = countryRepository.findAll();
return country;
}
}
Running spring-boot and opening localhost in chrome, the table shows up just fine.
However, looking at the Response tab under Network, it shows up like this
Shows the same thing if I go to http://localhost:8080/api
[{"alpha2":"AX","name":"AALAND ISLANDS","alpha3":"ALA","number":248},{"alpha2":"AF","name":"AFGHANISTAN","alpha3":"AFG","number":4},{"alpha2":"AL","name":"ALBANIA","alpha3":"ALB","number":8},{"alpha2":"DZ","name":"ALGERIA","alpha3":"DZA","number":12},{"alpha2":"AS","name":"AMERICAN SAMOA","alpha3":"ASM","number":16},{"alpha2":"AD","name":"ANDORRA","alpha3":"AND","number":20},{"alpha2":"AO","name":"ANGOLA","alpha3":"AGO","number":24},
Why does the Http Response return the "nbr" field as "number" instead? And how can I change it to show up as "nbr" in the Http response? Does something happen in the background in Spring Boot when formulating the http response that I can't control?

It is a number because you defined it as a number here, in Country entity:
#Column(name = "nbr")
private int nbr;
The best solution is to create another object which is used for HTTP communication. For example: CountryDTO.
In CountryDTO you can define nbr field as String.
Then you just have to create a mapping between Country and CountryDTO objects.
Why you should always do like this:
You should never send Entities directly to the client.
It keeps your code clean and separated: One object is responsible for holding the database model, and another is responsible for communicating with the client. It is now the same, and it is just pure luck.

Found out what happened, although I don't know the specifics.
spring uses Jackson to serialize, and Jackson uses by default public getters to serialize and name data.
Since I named the nbr getter/setters as getNumber() and setNumber, changing it to getNbr() and setNbr() respectively solved the issue.

How to set Nested Object with Mongotemplate Spring

I'm still new in mongodb, If I have a class like below and I want to set a property Role which is Object Type Property, how can I achieve it ? please check the class below
#Document(collection="User")
public class UserBean {
#Id
private String id;
private String userName;
private String password;
private RoleBean role;
}
#Document(collection="Role")
public class RoleBean {
#Id
private String id;
private String roleID;
private String roleName;
}
I need to set the UserBean's role property. So what is the best way to achieve it? Thanks.

Spring Mongo Template not saving the list of custom objects to MongoDb please see if this quation is already answered, or answer satisfies your requirements.

How to access the String json payload and mapping it to an Object in Spring rest controller?

I'm building a rest API using Spring Boot rest services.
I have a Java class:
class Person{
int id;
#notNull
String name;
#notNull
String password;
}
And I want to make an API to create a Person object. I will recieve a POST request with json body like:
{
"name":"Ahmad",
"password":"myPass",
"shouldSendEmail":1
}
As you can see there are an extra field "shouldSendEmail" that I have to use it to know if should I send an email or not after I create the Person Object.
I am using the following API:
#RequestMapping(value = "/AddPerson", method = RequestMethod.POST)
public String savePerson(
#Valid #RequestBody Person person) {
personRepository.insert(person);
// Here I want to know if I should send an email or Not
return "success";
}
Is there a method to access the value of "shouldSendEmail" while I using the autoMapping in this way?

There's many options for you solve. Since you don't want to persist the shouldSendEmail flag and it's ok to add into you domain class, you can use the #Transient annotation to tell JPA to skip the persistence.
#Entity
public class Person {
#Id
private Integer id;
#NotNull
private String name;
#NotNull
private String password;
#Transient
private Boolean shouldSendEmail;
}
If you want more flexible entity personalizations, I recommend using DTO`s.
MapStruct is a good library to handle DTO`s

You will need an intermediary DTO, or you will otherwise have to modify person to include a field for shouldSendEmail. If that is not possible, the only other alternative is to use JsonNode and manually select the properties from the tree.
For example,
#Getter
public class PersonDTO {
private final String name;
private final String password;
private final Integer shouldSendEmail;
#JsonCreator
public PersonDTO(
#JsonProperty("name") final String name,
#JsonProperty("password") final String password,
#JsonProperty("shouldSendEmail") final Integer shouldSendEmail
) {
this.name = name;
this.password = password;
this.shouldSendEmail = shouldSendEmail;
}
}

You can use #RequestBody and #RequestParam together as following
.../addPerson?sendEmail=true
So send the “sendEmail” value as request param and person as request body
Spring MVC - Why not able to use #RequestBody and #RequestParam together

You have mutli solutions
1 - You can put #Column(insertable=false, updatable=false) above this property
2 - send it as request param #RequestParam
#RequestMapping(value = "/AddPerson", method = RequestMethod.POST)
public String savePerson(
#Valid #RequestBody Person person, #RequestParam boolean sendMail) {}
3- use DTO lets say PersonModel and map it to Person before save

Web application spring boot and angular 5

I am making a simple CRUD application using Spring boot and MongoDB, the problem that I am facing is that I don't know how to define the model classes.
My application should be like this:
A site has some characteristics such as an ID, region, city, ... and contains 4 parts (cellulars) that each has its own characteristics. Any help would be appreciated.
This is what I have so far:
public class Site {
#Id
String siteId;
String projectPhase;
String region;
String city;
String siteName;
String newSiteName;
String clusterName ;
String longitude ;
String lattitude ;
#OneToMany(mappedBy = "siteId")
List L;
What I want to know is how do I associate another class inside this one.

Annotations like #OneToMany are typically used within JPA-context, and are unnecessary when using Spring Data MongoDB. This is also mentioned by the documentation:
There’s no need to use something like #OneToMany because the mapping framework sees that you want a one-to-many relationship because there is a List of objects.
You have a few options when you want to define one-to-many relations when using MongoDB. The first of them is to define them as embedded objects within the same document:
#Document
public class Site {
#Id
private String id;
private String city;
private String region;
private List<Part> cellulars;
}
public class Part {
private String characteristic1;
private String characteristic2;
}
This means that the parts do not exist on their own, so they don't need their own ID either.
Another possibility is to reference to another document:
#Document
public class Site {
#Id
private String id;
private String city;
private String region;
#DBRef
private List<Part> cellulars;
}
#Document
public class Part {
#Id
private String id;
private String characteristic1;
private String characteristic2;
}
In this case, parts are also separate documents, and a site simply contains a reference to the part.

Using ObjectId as String in Java (Manual reference) with spring-data mongodb

In MongoDB documentation they suggest to use ObjecId for manual references.
please see https://docs.mongodb.com/manual/reference/database-references/#document-references
original_id = ObjectId()
db.places.insert({
"_id": original_id,
"name": "Broadway Center",
"url": "bc.example.net"
})
db.people.insert({
"name": "Erin",
"places_id": original_id,
"url": "bc.example.net/Erin"
})
I'm using spring-data-mongodb and what I'm looking for is to have a People class defined like this:
#Document
public class People {
private String name;
#Reference // or any Annotation to convert an ObjectId to a String
private String placesId;
private String url;
}
How to have a "places_id" as ObjectId in mongoDB but mapped to a String in our POJO ?
I was expecting to have an annotation like #Reference but it seems to not be implemented.
I don't understand why we don't have this kind of annotation in spring-data-mongodb. I don't want to implement an explicit converter like suggested in spring documentation for all documents that use manual references.
Maybe it's not the right approach.
Did I miss something ?
UPDATE :
I like the idea to have a POJO using only String instead of ObjectId. Let's say I've got a class Place like this :
#Document
public class Place {
#Id
private String id;
private String name;
}
place.getId() will be a String but people.getPlaceId() will be an ObjectId. I want to avoid this unnecessary mapping.

The solution would be:
import org.springframework.data.mongodb.core.mapping.Field;
import org.springframework.data.mongodb.core.mapping.FieldType;
public class People {
#Field(targetType = FieldType.OBJECT_ID)
private String placesId;
}
This will map POJO string to ObjectId in MongoDB.

Why don't you leave the field as ObjectId?
#Document
public class People {
private String name;
private ObjectId placesId;
private String url;
}
If you want to query by this field you can do this:
For lists
List<String> ids // the ids as strings
List<ObjectId> objIds = ids .stream()
.map(i -> new ObjectId(i))
.collect(Collectors.toList());
For single String
String id // single id
ObjectId objId = new ObjectId(id);

If you want to make a real reference to an other object in your database, use the #DBRef annotation which is provided by Spring Data.
Your updated code could look like the following:
#Document
public class People {
private String name;
#DBRef
private Place place;
private String url;
}
Spring Data will then automatically map a Place object to your People object. Internally this is done with a reference to the unique ObjectId. Try this code and have a look at your mongo database.
For more information have a look at: MongoDb with java foreign key

I have a solution very simple:
#JsonSerialize(using= ToStringSerializer.class)
private ObjectId brandId;
...
put that on the attribute that is Object Id, and the ObjectId gets and inserts like string