[FIXED] avoid circular dependency on hibernate

Issue

package com.example.demo.model;

import com.sun.istack.NotNull;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.data.jpa.domain.support.AuditingEntityListener;

import javax.persistence.*;
import java.util.*;

@Data
@NoArgsConstructor
@AllArgsConstructor
@Entity
@EntityListeners(AuditingEntityListener.class)
@Table(name="MEDICAL_DEVICE")
public class MedicalDevice {

    public MedicalDevice(UUID deviceId, DefectPriority defectPriority, State currentState) {
        this.deviceId = deviceId;
        this.defectPriority = defectPriority;
        this.currentState = currentState;
    }

    public MedicalDevice(UUID deviceId, State currentState) {
        this.deviceId = deviceId;
        this.currentState = currentState;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;

    @Column(name="DEVICE_ID")
    @NotNull
    private UUID deviceId;

    @Column(name="DEFECT_PRIORITY", nullable = true)
    @Enumerated(EnumType.STRING)
    private DefectPriority defectPriority;

    @OneToMany(mappedBy="medicalDevice")
    private List<State> states = new ArrayList<>();

    @OneToOne(mappedBy="medicalDevice")
    private State currentState;



}

package com.example.demo.model;

import com.sun.istack.NotNull;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.NonNull;
import org.springframework.data.jpa.domain.support.AuditingEntityListener;

import javax.persistence.*;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.List;
import java.util.UUID;

@Data
@NoArgsConstructor
@AllArgsConstructor
@Entity
@EntityListeners(AuditingEntityListener.class)
@Table(name="STATE")
public class State {

    public State(StateNames state, UUID enteredBy, LocalDateTime enteredAt) {
        this.state = state;
        this.enteredBy = enteredBy;
        this.enteredAt = enteredAt;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;

    @Enumerated(EnumType.STRING)
    private StateNames state;

    @Column(name="USER_ID")
    private UUID enteredBy;       //User who changed the devices state to this one

    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="MEDICAL_DEVICE_ID")
    @NotNull
    private MedicalDevice medicalDevice;



    @Column(name = "LOCAL_DATE_TIME", columnDefinition = "TIMESTAMP")
    private LocalDateTime enteredAt;    //Time when the devices state was changed into this one

    @Column(name = "LOCAL_DATE", columnDefinition = "DATE")
    private LocalDate availabilityDate; //Date when a device will be available (only used in defect states and bought state)

    @OneToMany(mappedBy="state")
    private List<AdditionalInformation> additionalInformation;


}

how to avoid circular dependency on hibernate between State class and MedicalDevice class? I have implemented @OneToMany List which is the old states and @OneToOne State currentState which indicates the current state. I would like to have it separate not all in the list but my implementation causes that> enter image description here

Solution

Annotate MedicalAdvice object inside your State class with @JsonIgnore annotation. This way, you can prevent infinite recursive fetching of data from relationships between entity classes.

Answered By - DarkMode
Answer Checked By - Katrina (JavaFixing Volunteer)