I have an implementation of a REST front-end UI and a Spring JPA based backend.
In it, I have a class like this:
public class TaskInfo {
// 4 fields
private Parent parentList;
// 3 fields
// Getters and Setters
}
class Parent {
// Parent class code
}
When I try to take a Response, I find that in place of Parent, I get a null value. Why is this Parent object not getting serialized? Is there a workaround to this? Or should I just include the fields of Parent in this class directly?
Edit: I'm using Jackson for serialization.
For me the below works fine. I think this is equivalent to the code present in your question
package jackson;
import java.io.IOException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
public class TaskInfo {
public TaskInfo(String id, Parent parentList) {
super();
this.id = id;
this.parentList = parentList;
}
private String id;
private Parent parentList;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public Parent getParentList() {
return parentList;
}
public void setParentList(Parent parentList) {
this.parentList = parentList;
}
public static void main(String args[]) throws IOException {
Parent parent = new Parent("123");
TaskInfo taskInfo = new TaskInfo("taskID", parent);
String json = new ObjectMapper().writeValueAsString(taskInfo);
System.out.println(json);
}
}
class Parent {
public Parent(String parentId) {
this.parentId = parentId;
}
public String getParentId() {
return parentId;
}
public void setParentId(String parentId) {
this.parentId = parentId;
}
private String parentId;
// Parent class code
}
It prints the following output
{"id":"taskID","parentList":{"parentId":"123"}}
I used jackson
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.7.1</version>
</dependency>
It doesn't serialize because your properties are not public. Make the properties public and it works.
Related
I am building REST API using spring boot application. I have connected application to Mongodb database. I have created a database named "Employee" and collection as "Employee" itself. Now i want to create a document. I have three class. Class A, Class B and class C.
Class A is the parent Class having property (id,name,password). Class B is child class and extends Class A with property(address,phoneNumber) and class C is child class which also extends class A with property (fatherName,MotherName).
Now i want to add the data to database as object of B or object of C and also want to retrive the data from database as object of B or Object of C.
here is code of Class A:
package com.example.webproject;
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;
#Document(collection="Employee")
public class A {
#Id
private String id;
private String passwd;
private String username;
public String getId() {
return id;
}
public void setIp(String string) {
this.ip = string;
}
public String getPasswd() {
return passwd;
}
public void setPasswd(String passwd) {
this.passwd = passwd;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
class B:
package com.example.webproject;
public class B extends A {
private String address;
private String phoneNumber;
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber= phoneNumber;
}
}
Class C :
package com.example.webproject;
public class C extends A {
private String fatherName;
private String motherName;
public String getFatherName() {
return fatherName;
}
public void setFatherName(String fatherName) {
this.fatherName = fatherName;
}
public String getMotherName() {
return motherName;
}
public void setMotherName(String motherName) {
this.motherName = motherName;
}
}
EmployeeRepository.java
package com.example.webproject;
import org.springframework.data.mongodb.repository.MongoRepository;
import org.springframework.stereotype.Repository;
#Repository
public interface EmployeeRepository extends MongoRepository<A,String> {}
EmployeeController.java
#RestController
public class EmployeeController {
#Autowired
private EmployeeRepository repo;
#PostMapping("/addByB")
public String addDataByB(#RequestBody B res) {
repo.save(res);
return "added";
}
#PostMapping("/addByC")
public String addDataByC(#RequestBody C res) {
repo.save(res);
return "added";
}
#GetMapping("/getByB")
public List<B> getDataByB(){
List<B> b= repo.findAll(); #Here it throws error because repo.findAll return object of A.
return b;
}
When i try to add data as B object or C object using swagger , the data is getting stored in database. Now i want to retrieve the data as B object or C object, how to achieve this?
Because you just create Repository of class A and call it, you nedd to creat two another repo of class B and C then call them like you call " EmployeeRepository " so you can use them and get the data.
is it posible to generate a custom "presence checking" method name, being a method of the property itself rather the owning object?
I know I can use hasProperty() methods to check for presence of a value...
https://mapstruct.org/documentation/stable/reference/html/#source-presence-check
but with Optional or JsonNullable (from OpenApi nonullable) that checking method is on the property itself, not on the owning object... :-(
I can map JsonNullable or Optional easyly 'using' or extending a simple custom Mapper
#Mapper
public class JsonNullableMapper {
public <T> T fromJsonNullable(final JsonNullable<T> jsonNullable) {
return jsonNullable.orElse(null);
}
public <T> JsonNullable<T> asJsonNullable(final T nullable) {
return nullable != null ? JsonNullable.of(nullable) : JsonNullable.undefined();
}
}
what I would like to achieve is something like this as "presence check":
if(source.getProperty().isPresent()) {
target.set(customMapper.map(source.getProperty()));
}
Any one found a solution for this?
Thanks and regards
I have managed to implement custom lombok extension which generates "presence checknig" methods.
Here is an example project. In short I added #PresenceChecker annotation and implemented Lombok Javac Annotation handler.
It's possible to use it together with other Lombok annotations:
#Getter
#Setter
public class User {
private String name;
}
#Getter
#Setter
#PresenceChecker
public class UserUpdateDto {
private String name;
}
//MapStruct Mapper interface declaration
#Mapper
public interface UserMapper {
void updateUser(UserUpdateDto dto, #MappingTarget User user);
}
Generated code:
public class User {
private String name;
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
}
public class UserUpdateDto {
private boolean hasName;
private String name;
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
this.hasName = true;
}
public boolean hasName() {
return this.hasName;
}
}
//MapStruct Mapper implementation
public class UserMapperImpl implements UserMapper {
#Override
public void updateUser(UserUpdateDto dto, User user) {
if ( dto == null ) {
return;
}
if ( dto.hasName() ) {
user.setName( dto.getName() );
}
}
}
The answer is unfortunately a straight no.
It is not possible in the current version of MapStruct (1.3.1final) and its not on the shortlist for 1.4.0. You could open up an issue on the git repo of MapStruct as feature request.
I am building a simple REST service using spring. I separated my entities from DTOs and I made the DTOs immutable using Immutables. I needed mapping between DTOs and DAOs, so I chose MapStruct. The Mapper is not able to detect the setters I have defined in my DAOs.
The problem is exactly similar to this question. This question does not have an accepted answer and I have tried all of the suggestions in that question and they don't work. I don't want to try this answer because I feel it defeats the purpose for which I am using Immutables. #marc-von-renteln summarizes this reason nicely in the comment here
I tried the answer provided by #tobias-schulte. But that caused a different problem. In the Mapper class in the answer, trying to return Immutable*.Builder from the mapping method throws an error saying the Immutable type cannot be found.
I have exhaustively searched issues logged against MapStruct and Immutables and I haven't been able to find a solution. Unfortunately there are hardly few examples or people using a combination of MapStruct and Immutables. The mapstruct-examples repository also doesn't have an example for working with Immutables.
I even tried defining separate Mapper interfaces for each of the DtTOs (like UserStatusMapper). I was only making it more complicated with more errors.
I have created a sample spring project to demonstrate the problem.
GitHub Repo Link. This demo app is almost same as the REST service I am creating. All database (spring-data-jpa , hibernate) stuff is removed and I am using mock data.
If you checkout the project and run the demo-app you can make two API calls.
GetUser:
Request:
http://localhost:8080/user/api/v1/users/1
Response:
{
"id": 0,
"username": "TestUser",
"email": "TestUser#demo.com",
"userStatus": {
"id": 1,
"status": 1,
"statusName": "Active"
}
Createuser: PROBLEM HERE
http://localhost:8080/user/api/v1/users/create
Sample Input:
{
"username": "TestUser",
"email": "TestUser#demo.com",
"userStatus": {
"id": 1,
"status": 1,
"statusName": "Active"
}
}
Response:
{
"timestamp": "2019-04-28T09:29:24.933+0000",
"status": 500,
"error": "Internal Server Error",
"message": "Type definition error: [simple type, class com.immutablesmapstruct.demo.dto.model.ImmutableUserDto$Builder]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.immutablesmapstruct.demo.dto.model.ImmutableUserDto$Builder`, problem: Cannot build UserDto, some of required attributes are not set [username, email, userStatus]\n at [Source: (PushbackInputStream); line: 9, column: 1]",
"path": "/user/api/v1/users/create"
}
Below are important pieces of code related to problem:
Daos:
1. UserDao
public class User {
// Primary Key. Something that is annotated with #Id
private int id;
private String username;
private String email;
private UserStatus userStatus;
private User(Builder builder) {
id = builder.id;
username = builder.username;
email = builder.email;
userStatus = builder.userStatus;
}
public static Builder builder() {
return new Builder();
}
public int getId() {
return id;
}
public String getUsername() {
return username;
}
public String getEmail() {
return email;
}
public UserStatus getUserStatus() {
return userStatus;
}
public static final class Builder {
private int id;
private String username;
private String email;
private UserStatus userStatus;
private Builder() {
}
public Builder setId(int id) {
this.id = id;
return this;
}
public Builder setUsername(String username) {
this.username = username;
return this;
}
public Builder setEmail(String email) {
this.email = email;
return this;
}
public Builder setUserStatus(UserStatus userStatus) {
this.userStatus = userStatus;
return this;
}
public User build() {
return new User(this);
}
2. UserStatusDao:
package com.immutablesmapstruct.demo.dao.model;
/**
* Status of user.
* Example: Active or Inactive
*/
public class UserStatus {
// Primary Key. Something that is annotated with #Id
private int id;
// A value of 1 or 0
private int status;
// Active , InActive
private String statusName;
private UserStatus(Builder builder) {
id = builder.id;
status = builder.status;
statusName = builder.statusName;
}
public static Builder builder() {
return new Builder();
}
public int getId() {
return id;
}
public int getStatus() {
return status;
}
public String getStatusName() {
return statusName;
}
public static final class Builder {
private int id;
private int status;
private String statusName;
private Builder() {
}
public Builder setId(int id) {
this.id = id;
return this;
}
public Builder setStatus(int status) {
this.status = status;
return this;
}
public Builder setStatusName(String statusName) {
this.statusName = statusName;
return this;
}
public UserStatus build() {
return new UserStatus(this);
}
}
}
DTOs
1. UserDto:
package com.immutablesmapstruct.demo.dto.model;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import org.immutables.value.Value;
#Value.Immutable
#Value.Style(defaults = #Value.Immutable(copy = false), init = "set*")
#JsonSerialize(as = ImmutableUserDto.class)
#JsonDeserialize(builder = ImmutableUserDto.Builder.class)
public abstract class UserDto {
#Value.Default
#JsonProperty
public int id() {
return 0;
}
#JsonProperty
public abstract String username();
#JsonProperty
public abstract String email();
#JsonProperty
public abstract UserStatusDto userStatus();
2. UserStatusDto:
package com.immutablesmapstruct.demo.dto.model;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import org.immutables.value.Value;
#Value.Immutable
#Value.Style(defaults = #Value.Immutable(copy = false), init = "set*")
#JsonSerialize(as = ImmutableUserStatusDto.class)
#JsonDeserialize(builder = ImmutableUserStatusDto.Builder.class)
public abstract class UserStatusDto {
#JsonProperty
public abstract int id();
#JsonProperty
public abstract int status();
#JsonProperty
public abstract String statusName();
}
MapStruct UserMapper:
package com.immutablesmapstruct.demo.dto.mapper;
import com.immutablesmapstruct.demo.dao.model.User;
import com.immutablesmapstruct.demo.dao.model.UserStatus;
import com.immutablesmapstruct.demo.dto.model.UserDto;
import com.immutablesmapstruct.demo.dto.model.UserStatusDto;
import org.mapstruct.Mapper;
import org.mapstruct.factory.Mappers;
#Mapper(componentModel = "spring")
public interface UserMapper {
UserMapper USER_MAPPER_INSTANCE = Mappers.getMapper(UserMapper.class);
UserDto userDaoToDto(User user);
//Problem here.
User userDtoToDao(UserDto userDto);
UserStatusDto userStatusDaoToDto(UserStatus userStatusDao);
UserStatus userStatusDtoToDao(UserStatusDto userStatusDto);
}
If I look at the concrete method generated by MapStruct for userDtoToDao I can clearly see that the setters are not being recognized.
package com.immutablesmapstruct.demo.dto.mapper;
#Generated(
value = "org.mapstruct.ap.MappingProcessor",
date = "2019-04-28T02:29:03-0700",
comments = "version: 1.3.0.Final, compiler: javac, environment: Java 1.8.0_191 (Oracle Corporation)"
)
#Component
public class UserMapperImpl implements UserMapper {
...
...
#Override
public User userDtoToDao(UserDto userDto) {
if ( userDto == null ) {
return null;
}
com.immutablesmapstruct.demo.dao.model.User.Builder user = User.builder();
return user.build();
}
....
....
}
Mapstruct doesn't recognize your getters in UserDto and UserStatusDto.
When you change the existing methods (like public abstract String username()) in these abstract classes to classic getters like
#JsonProperty("username")
public abstract String getUsername();
the MapperImpl will contain the required calls. Note, that the #JsonProperty needs to have the attributes name itself afterwards (because of the changed method name).
Here are the complete classes UserDto and UserStatusDto with said changes:
package com.immutablesmapstruct.demo.dto.model;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import org.immutables.value.Value;
#Value.Immutable
#Value.Style(defaults = #Value.Immutable(copy = false), init = "set*")
#JsonSerialize(as = ImmutableUserDto.class)
#JsonDeserialize(builder = ImmutableUserDto.Builder.class)
public abstract class UserDto {
#Value.Default
#JsonProperty("id")
public int getId() {
return 0;
}
#JsonProperty("username")
public abstract String getUsername();
#JsonProperty("email")
public abstract String getEmail();
#JsonProperty("userStatus")
public abstract UserStatusDto getUserStatus();
}
package com.immutablesmapstruct.demo.dto.model;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import org.immutables.value.Value;
#Value.Immutable
#Value.Style(defaults = #Value.Immutable(copy = false), init = "set*")
#JsonSerialize(as = ImmutableUserStatusDto.class)
#JsonDeserialize(builder = ImmutableUserStatusDto.Builder.class)
public abstract class UserStatusDto {
#JsonProperty("id")
public abstract int getId();
#JsonProperty("status")
public abstract int getStatus();
#JsonProperty("statusName")
public abstract String getStatusName();
}
I have created a sample project with following code. Even if i am not providing table create statement in the data.sql, it is creating the table. how to stop that. Sample code is present below
Can you please let me know what I am doing wrong? I have removed the import statements below as the post was not allowing to put so much code here.
package com.example.demo;
// Model class
#Entity
#Table(name="reservation")
public class Reservation {
#Id
private Long id;
#Column(name="user_id")
private Long userId;
#Column(name="party_size")
private int partySize;
#Column(name="restaurant_id")
private Long restaurantId;
#Column(name="date")
private LocalDateTime dt;
public Reservation() {}
public Reservation(Long id, Long userId, int partySize) {
this.id = id;
this.userId = userId;
this.partySize = partySize;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public Long getUserId() {
return userId;
}
public void setUserId(Long userId) {
this.userId = userId;
}
public int getPartySize() {
return partySize;
}
public void setPartySize(int partySize) {
this.partySize = partySize;
}
public Long getRestaurantId() {
return restaurantId;
}
public void setRestaurantId(Long restaurantId) {
this.restaurantId = restaurantId;
}
public LocalDateTime getDt() {
return dt;
}
public void setDt(LocalDateTime dt) {
this.dt = dt;
}
}
package com.example.demo;
#SpringBootApplication
public class ReservationApp {
public static void main(String[] args) {
SpringApplication.run(ReservationApp.class, args);
}
}
package com.example.demo;
#RestController
#RequestMapping("/v1")
public class ReservationController {
#Autowired
private ReservationService reservationService;
// ------------ Retrieve all reservations ------------
#RequestMapping(value = "/reservations", method = RequestMethod.GET)
public List getAllReservations() {
return reservationService.getAllReservations();
}
package com.example.demo;
import org.springframework.data.repository.CrudRepository;
public interface ReservationRepository extends CrudRepository<Reservation,String> {
}
package com.example.demo;
#Service
public class ReservationService {
#Autowired
private ReservationRepository reservationRepository;
// Retrieve all rows from table and populate list with objects
public List getAllReservations() {
List reservations = new ArrayList<>();
reservationRepository.findAll().forEach(reservations::add);
return reservations;
}
}
try to remove the spring boot hibernate configuration
spring.jpa.hibernate.ddl-auto = update
Which is able of creating/updating the database schema from entities
To disable automatic DDL generation, set the following property to false in application.properties:
spring.jpa.generate-ddl = false
For more information and fine-grained control, please see the documentation.
Set the ddl generation to none in the application.properties:
spring.jpa.hibernate.ddl-auto=none
I am getting this exception every time i try to query a view on Couchbase DB from my spring boot application.
Unsupported parameter type for key: class com.couchbase.client.protocol.views.Query.
I was setting a string on setKey() method of Query class, got an exception. But then I checked the API and provided a json to setKey, still not working. Have searched a lot but could not get this to work.
I am sharing the code snippet in this post as well.
Application.properties
spring.couchbase.bucket.password=
spring.couchbase.bucket.name=default
spring.couchbase.bootstrap-hosts=127.0.0.1
spring.data.couchbase.repositories.enabled=true
PlayerRepository
public interface PlayerRepository extends CouchbaseRepository<Player, Integer>
{
#View(designDocument = "player", viewName = "all")
public List<Player> findAll();
#View(designDocument = "player", viewName = "by_Name")
public Player findByName(Query query);
#View(designDocument = "player", viewName = "by_TeamId")
public List<Player> findByTeamId(Query query);
}
Player.java
#Document
public class Player
{
#Id
int playerId;
#Field
String name;
#Field
String type;
#Field
String country;
#Field
String playingHand;
#Field
String era;
#Field
int teamId;
#Field
int odiCenturies;
#Field
int testCenturies;
public Player(){}
public Player(int playerId, String name, String type, String country, String playingHand, String era, int teamId,
int odiCenturies, int testCenturies) {
super();
this.playerId = playerId;
this.name = name;
this.type = type;
this.country = country;
this.playingHand = playingHand;
this.era = era;
this.teamId = teamId;
this.odiCenturies = odiCenturies;
this.testCenturies = testCenturies;
}
SpringBootApplication class
#SpringBootApplication
public class CricketTeamSelectionMain
{
/**
* #param args
*/
public static void main(String[] args)
{
SpringApplication.run(CricketTeamSelectionMain.class, args);
}
#Configuration
#EnableCouchbaseRepositories
public static class DBConfig extends AbstractCouchbaseConfiguration
{
#Value("${spring.couchbase.bucket.name}")
private String bucketName;
#Value("${spring.couchbase.bucket.password}")
private String password;
#Value("${spring.couchbase.bootstrap-hosts}")
private String ip;
#Override
public String getBucketName() {
return this.bucketName;
}
#Override
public String getBucketPassword() {
return this.password;
}
#Override
public List<String> getBootstrapHosts() {
return Arrays.asList(this.ip);
}
}
}
PlayerService class
package org.ups.fantasyCricket.service;
import java.net.URI;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.ups.fantasyCricket.CricketTeamSelectionMain.DBConfig;
import org.ups.fantasyCricket.Model.Player;
import org.ups.fantasyCricket.Repository.PlayerRepository;
import com.couchbase.client.CouchbaseClient;
import com.couchbase.client.protocol.views.Query;
import com.couchbase.client.protocol.views.View;
import com.couchbase.client.protocol.views.ViewResponse;
#Service
public class PlayerService
{
#Autowired
PlayerRepository playerRepo;
private CouchbaseClient client;
public List<Player> getAllPlayers()
{
List<Player> allPlayerLists = new ArrayList<Player>();
/*allPlayerLists.addAll((Collection<? extends Player>) playerRepo.findAll());
return allPlayerLists;*/
playerRepo.findAll().forEach(allPlayerLists::add);
return allPlayerLists;
}
public Player getPlayerByName(String name)
{
DBConfig dbCon = new DBConfig();
try
{
Query query = new Query();
query.setIncludeDocs(true);
query.setKey(name);
Player player = playerRepo.findByName(query);
return player;
}
catch(Exception e)
{
e.printStackTrace();
System.out.println(e.getMessage());
}
return null;
}
public String addPlayer(Player player)
{
playerRepo.save(player);
return "Success";
}
public String updatePlayer(Player player, int id)
{
playerRepo.save(player);
return "Success";
}
public List<Player> getPlayersByTeamId(int teamId)
{
List<Player> allPlayerLists = new ArrayList<Player>();
Query query = new Query();
query.setKey(String.valueOf(teamId));
playerRepo.findByTeamId(query).forEach(allPlayerLists::add);
return allPlayerLists;
}
public String addPlayers(List<Player> players)
{
playerRepo.save(players);
return "Success";
}
}
View by_Name on CouchBase DB
function (doc) {
emit(doc.name, doc);
}
Which version of spring-data-couchbase are you using? Starting with 2.x, the #Query annotation uses query derivation and you cannot use a ViewQuery as a parameter anymore... Have a look at the docs, on query derivation with a view.
You could probably use the CouchbaseTemplate to perform a manual query though.