I am using Java and Sprig boot with MySQL to create an employee tracker. there are to models: Employee and Company. The Company model just has an autogenerated Id and name. The employee has first_name, last_name, address, salary, company_id, and email_id. The Employee Model belongs to Company model, and it is a oneToMany relationship (because one company has many employees. I am trying to set it up so that the Employee model is linked to the Company model. When I try and run spring boot i get this error:

Use of @OneToMany or @ManyToMany targeting an unmapped class: employeeapps.com.example.EmployeeTracker.model.Employee.company[employeeapps.com.example.EmployeeTracker.model.Company]

Here is my Employee Model:

package employeeapps.com.example.EmployeeTracker.model;

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

@Entity
@Table(name = "employees")
public class Employee {


    //Company is one and has many employees
    @OneToMany(mappedBy = "employees")
    private Set<Company> company;


    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long companyId;

    @Column(name = "first_name")
    private String firstName;

    @Column(name = "last_name")
    private String lastName;

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

    @Column(name="salary")
    private Double salary;

    @Column(name = "email_id")
    private String emailId;


    //default constructor
    public Employee(){

    }






    //create a public constructor with the appropriate parameters to be able to create a new instance of an employee
    public Employee(String firstName, String lastName, String emailId, String address, Double salary){
        super();
        this.firstName = firstName;
        this.lastName = lastName;
        this.emailId = emailId;
        this.salary = salary;
        this.address = address;
    }

    //define methods
    //long data type because could be a very long numerical  data
    public long getId() {
        return companyId;
    }

    public void setId(long companyId){
        this.companyId = companyId;
    }

    public String getFirstName(){
        return firstName;
    }
    public void setFirstName(String firstName){
        this.firstName = firstName;
    }
    public String getLastName(){
        return lastName;
    }
    public void setLastName(String lastName){
        this.lastName = lastName;
    }
    public String getEmailId(){
        return emailId;
    }
    public void setEmailId(String emailId){
        this.emailId = emailId;
    }

    public void setAddress(String address){
        this.address = address;
    }

    public void setSalary(Double salary){
        this.salary = salary;
    }

Here is my Compay Model:

package employeeapps.com.example.EmployeeTracker.model;


import javax.persistence.*;

@Table(name = "company")
public class Company {

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

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

    public Company(){

    }

    //public constructor

    public Company(String name){
        this.name = name;

    }

}

Here is my employee controller to preform REST API:

package employeeapps.com.example.EmployeeTracker.controller;

import employeeapps.com.example.EmployeeTracker.model.Employee;
import employeeapps.com.example.EmployeeTracker.repository.employeeRepository;
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 java.util.List;

@RestController
@RequestMapping("/api/v1")
public class EmployeeController {

    @Autowired
   private employeeRepository employeeRepository;


    //REST APIS
    //get all employees  method name is get all

    @GetMapping("/employees")
    public List<Employee> getAllEmployees(){
        return employeeRepository.findAll();

    }
}

CodePudding user response：

In the company model give the model @Entity annotation above @Table annotation.

CodePudding user response：

Add below line to your system.properties file

 spring.mvc.pathmatch.matching-strategy=ant_path_matcher

In employees class use :

 @OneToMany(targetEntity = Employee.class,cascade = ALL,fetch = 
 FetchType.LAZY)  
 @JoinColumn(name = "employee_id",referencedColumnName = "company_id")  
 private Set<Company> company;  

CodePudding user response：

You should make the company an entity because you cannot make mapping without making the model class into the entity.Use @Entity to make company class entity above @Table(name = company). As you are trying to map from employees(many) entity to company(one)entity try @ManyToOne mapping in the employees entity by making company_ id a FOREIGN KEY in employee table

@ManyToOne
@JoinColumn(name="id",referencedColumnName="company_id")
 private Set<Company> company;

In the above name represents id of company in company entity and referencedColumnName represents company_id in the employee entity.