Problema com os dados de registo recuperados de mysql db usando springboot e hibernação

Iredafe Owolabi:

Eu estou tentando obter um registo da base de dados mysql usando uma api Springboot descansar, mas os logs são provenientes de várias repetições em vez de apenas uma linha. Eu só tenho dados em uma linha no meu banco de dados, mas quando ele é chamado usando o GET, ele vem como registros repetitivos. Verifique a imagem para vê-la:

Abaixo está o código para as classes de entidades que produziram esses logs. Primeiro é UserLog:

package com.dafe.spring.applogger.entity;

import java.util.ArrayList;
import java.util.List;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
@Table(name="log")
public class UserLog {

    //define field

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id;

    @Column(name="user_id")
    private String userId;

    @Column(name="session_id")
    private String sessionId;

    @OneToMany(mappedBy="userLog",cascade=CascadeType.ALL)
        private List<Action>action;
    //define constructors

    public UserLog() {

    }

    public UserLog(String userId, String sessionId) {
        this.userId = userId;
        this.sessionId = sessionId;
    }
    //define getters and setters


    public String getUserId() {
        return userId;
    }


    public void setUserId(String userId) {
        this.userId = userId;
    }


    public String getSessionId() {
        return sessionId;
    }


    public void setSessionId(String sessionId) {
        this.sessionId = sessionId;
    }

    public List<Action> getAction() {
        return action;
    }


    public void setAction(List<Action> action) {
        this.action = action;
    }

    @Override
    public String toString() {
        return "Log [userId=" + userId + ", sessionId=" + sessionId + "]";
    }

}

Aqui é a outra classe de entidade Ação:

package com.dafe.spring.applogger.entity;

import java.sql.Timestamp;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;


@Entity
@Table(name="action")
public class Action {

    //declare & annotate your fields
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="id")
    private int id;

@Column(name="time")
    private Timestamp time;

@Column(name="type")
    private String type;


@ManyToOne
@JoinColumn(name="log_id")
private UserLog userLog;

public Action(int id, Timestamp time, String type, UserLog userLog) {
    this.id = id;
    this.time = time;
    this.type = type;
    this.userLog = userLog;
}

    //create and generate constructor
    public Action() {

    }

    public Action(Timestamp time, String type, UserLog userLog) {
        this.time = time;
        this.type = type;
        this.userLog = userLog;
    }

    //generate getters and setters

    public Timestamp getTime() {
        return time;
    }

    public void setTime(Timestamp time) {
        this.time = time;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public UserLog getUserLog() {
        return userLog;
    }

    public void setUserLog(UserLog userLog) {
        this.userLog = userLog;
    }
    //generate toString 

    @Override
    public String toString() {
        return "Action [time=" + time + ", type=" + type + ", userLog=" + userLog + "]";
    }


}

aqui é a classe de implementação dao

package com.dafe.spring.applogger.dao;

import java.util.List;

import javax.persistence.EntityManager;

import org.hibernate.Session;
import org.hibernate.query.Query;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import com.dafe.spring.applogger.entity.UserLog;

@Repository
public class UserLogDaoHibernateImplementation implements UserLogDAO {


    //define field for entity manager
    private EntityManager entityManager;

    //set up constructor injection
    @Autowired
    public UserLogDaoHibernateImplementation(EntityManager theEntityManager) {

    entityManager= theEntityManager;
    }

    @Override
    public List<UserLog> findAll() {

        //get the current hibernate session from entity manager
        Session currentSession = entityManager.unwrap(Session.class);


        //create a query
        Query <UserLog> theQuery = 
                currentSession.createQuery("from UserLog", UserLog.class);

        //execute query and get result list

        List<UserLog> userLog = theQuery.getResultList();

        //return the results

        return userLog;
    }

    @Override
    public UserLog findById(int theId) {

        //get the current session
        Session currentSession = entityManager.unwrap(Session.class);

        //get the userLog
        UserLog userLog = 
                currentSession.get(UserLog.class, theId);


        //return the userLog

        return null;
    }

    @Override
    public void save(UserLog theUserLog) {
        //get the current session
        Session currentSession = entityManager.unwrap(Session.class);

        //save
    currentSession.saveOrUpdate(theUserLog);

    }

    @Override
    public void deleteById(int theId) {
        //get the current hibernate session
                Session currentSession = entityManager.unwrap(Session.class);

    //delete object with primary key
                Query theQuery = 
                        currentSession.createQuery("delete from log where id=:theuserId");

                theQuery.setParameter("theuserId", theId);

                theQuery.executeUpdate();

    }

} 

eo controlador de descanso

package com.dafe.spring.applogger.rest;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.dafe.spring.applogger.dao.UserLogDAO;
import com.dafe.spring.applogger.entity.UserLog;
// this api selects all the 
@RestController
@RequestMapping("/api")
public class UserLogRestController {

    @Autowired
    private UserLogDAO userLogDao;

    //inject logDao using constructor injection
        public UserLogRestController(UserLogDAO theUserLogDao) {

    }

    //expose logs and return list of logs
    @GetMapping("/userLog")
    public List<UserLog> findAll(){

        return userLogDao.findAll();

    }

}

Por favor me ajude a descobrir isso. desde já, obrigado

kokuone:

Eu tive esse problema recentemente e eu ter corrigido colocando este @JsonIgnore anottation em relacionamentos, você pode tentar se ele funciona para você também

 @JsonIgnore
 @ManyToOne
 @JoinColumn(name="log_id")
 private UserLog userLog;


 @JsonIgnore
 @OneToMany(mappedBy="userLog",cascade=CascadeType.ALL)
 private List<Action>action;