Updating primary key for spring boot entity manager jpa

Question

i need to update tow columns inside my table (Job this table is joint with two other tables employees and job-history)one of them is the primary key, but i get error, if someone can help.

    package com.touati.org.model;
import java.io.Serializable;
import javax.persistence.*;
import java.math.BigDecimal;
import java.util.List;


/**
 * The persistent class for the jobs database table.
 * 
 */
@Entity
@Table(name="jobs")
@NamedQuery(name="Job.findAll", query="SELECT j FROM Job j")
public class Job implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="JOB_ID")
    private String jobId;

    @Column(name="JOB_TITLE")
    private String jobTitle;

    @Column(name="MAX_SALARY")
    private BigDecimal maxSalary;

    @Column(name="MIN_SALARY")
    private BigDecimal minSalary;

    //bi-directional many-to-one association to Employee
    @OneToMany(mappedBy="job")
    private List<Employee> employees;

    //bi-directional many-to-one association to JobHistory
    @OneToMany(mappedBy="job")
    private List<JobHistory> jobHistories;

    public Job() {
    }

    public String getJobId() {
        return this.jobId;
    }

    public void setJobId(String jobId) {
        this.jobId = jobId;
    }

    public String getJobTitle() {
        return this.jobTitle;
    }

    public void setJobTitle(String jobTitle) {
        this.jobTitle = jobTitle;
    }

    public BigDecimal getMaxSalary() {
        return this.maxSalary;
    }

    public void setMaxSalary(BigDecimal maxSalary) {
        this.maxSalary = maxSalary;
    }

    public BigDecimal getMinSalary() {
        return this.minSalary;
    }

    public void setMinSalary(BigDecimal minSalary) {
        this.minSalary = minSalary;
    }

    public List<Employee> getEmployees() {
        return this.employees;
    }

    public void setEmployees(List<Employee> employees) {
        this.employees = employees;
    }

    public Employee addEmployee(Employee employee) {
        getEmployees().add(employee);
        employee.setJob(this);

        return employee;
    }

    public Employee removeEmployee(Employee employee) {
        getEmployees().remove(employee);
        employee.setJob(null);

        return employee;
    }

    public List<JobHistory> getJobHistories() {
        return this.jobHistories;
    }

    public void setJobHistories(List<JobHistory> jobHistories) {
        this.jobHistories = jobHistories;
    }

    public JobHistory addJobHistory(JobHistory jobHistory) {
        getJobHistories().add(jobHistory);
        jobHistory.setJob(this);

        return jobHistory;
    }

    public JobHistory removeJobHistory(JobHistory jobHistory) {
        getJobHistories().remove(jobHistory);
        jobHistory.setJob(null);

        return jobHistory;
    }

}

my controller: here when i try to look for all job in the data base it works fine, also if i try to update juste the title of the job it works fine to but in case that i try to set a new primary key for the job table it gives me error here my controller.

package com.touati.org.model;

import java.io.IOException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;







@Controller    // This means that this class is a Controller
@RequestMapping(path="/project") // This means URL's start with /demo (after Application path)
public class MainController {



    @GetMapping(path="/job")
    public @ResponseBody Iterable<Job> getAllJob() {
        // This returns a JSON or XML with the users
        return jobRepository.findAll();
    }




    @GetMapping(path="/job/{jobId}")
    public @ResponseBody String getJob(@PathVariable String jobId) {
        Job job = jobRepository.findOne(jobId);

        try {
        job.setJobTitle("manager");
        job.setJobId("test1");
       jobRepository.save(job);
        }
        catch (Exception ex) {
            return "Error updating the job: " + ex.toString();
        }
        return "Job succesfully updated!";



    }

}

i got this error,

Error updating the user: org.springframework.orm.jpa.JpaSystemException: identifier of an instance of com.touati.org.model.Job was altered from test to test1; nested exception is org.hibernate.HibernateException: identifier of an instance of com.touati.org.model.Job was altered from test to test1

Thank you for your help.

Answer 1

Primary key should never be changed. If you need to change primary key it means your design is bad. If you need to change JOB_ID often then create another column for your primary key like ID. Another possibility is to copy all attributes and create new record with new JOB_ID and then remove old one.