java - 更新 Spring Boot 实体管理器 jpa 的主键

Question

我需要更新表中的两列(作业此表与其他两个表员工和工作历史记录相连)其中一个是主键，但如果有人可以提供帮助，我会收到错误。

    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;
    }

}

我的 Controller :在这里，当我尝试在数据库中查找所有作业时，它工作正常，而且如果我尝试仅更新作业的标题，它也可以正常工作，但如果我尝试设置新的主要工作作业表的键它给我错误在这里我的 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!";



    }

}

我收到此错误，

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

感谢您的帮助。

Answer 1

主键不应更改。如果您需要更改主键，则意味着您的设计很糟糕。如果您需要经常更改 JOB_ID，请为主键创建另一列，例如 ID。另一种可能性是复制所有属性并使用新的 JOB_ID 创建新记录，然后删除旧的记录。