如何将 HashMap 添加到员工列表 class

Question

I have created a Java class and using JPA to retrieving details of Employee class which is returning list of employees like

[
  {
    "empId": "1",
    "empName": "emp1",
    "empTag": "empTag1",
    "empState": "ACTIVE"
  },
  {
    "empId": "2",
    "empName": "emp2",
    "empTag": "empTag2",
    "empState": "ACTIVE"
  }
]

After receiving list of hash I want to add few dummy entries like

[
  {
    "empId": "00",
    "empName": "DummyEmp",
    "empTag": "DummyEmpTag",
    "empState": "ACTIVE"
  },
  {
    "empId": "1",
    "empName": "emp1",
    "empTag": "empTag1",
    "empState": "ACTIVE"
  },
  {
    "empId": "2",
    "empName": "emp2",
    "empTag": "empTag2",
    "empState": "ACTIVE"
  }
]

So I am trying to add map into list of employee but at the run time I am getting

java.lang.ClassCastException: java.util.HashMap$KeySet cannot be cast to com.domain.EmployeeBean 

My Employee Class:

@Table(name = "employee")
@Entity
public class EmployeeBean implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id @Column(name = "emp_id") 
    private String empId;
    
    @Column(name = "emp_name") 
    private String empName;
    
    @Column(name = "emp_tag") 
    private String empTag;
    
    @Column(name = "emp_state") 
    private String empState;

    .... (getters and setters) 
}

Repository:-

public interface EmployeeBeanRepository extends JpaRepository<EmployeeBean, String>{

    List < EmployeeBean > findByEmpState(String empState);

Resource:-

@RestController
@RequestMapping("/empDetails")
public class EmployeeBeanResource {
    
private final EmployeeBeanRepository empBeanRepository;
    
    public EmployeeBeanResource(EmployeeBeanRepository empBeanRepository) {
        this.empBeanRepository = empBeanRepository;
    }
        
    @GetMapping("/empState/{empState}")
    @Timed
    public List<EmployeeBean> getEmployeesByStatus(@PathVariable String empState) {
        List<EmployeeBean> activeEmployeeList = empBeanRepository.findByEmpState(empState);
        
        Map<String, String> empDummy = new HashMap<>();
        
        empDummy.put("empId", "00");
        empDummy.put("empName", "DummyEmp");
        empDummy.put("empTag", "DummyEmpTag");
        empDummy.put("empState", "ACTIVE");
        
        activeEmployeeList.add((EmployeeBean) empDummy.keySet());
        activeEmployeeList.add((EmployeeBean) empDummy.values());
       
        return activeEmployeeList;
    }
}

I have tried a lot but still unable to figure out a way to add map in to list of employee.

Answer 1

Instead of this:

Map<String, String> empDummy = new HashMap<>();
        
empDummy.put("empId", "00");
empDummy.put("empName", "DummyEmp");
empDummy.put("empTag", "DummyEmpTag");
empDummy.put("empState", "ACTIVE");
        
activeEmployeeList.add((EmployeeBean) empDummy.keySet());

try the following:

EmployeeBean empDummy = new EmployeeBean();
        
empDummy.setEmpId("00");
empDummy.setEmpName("DummyEmp");
empDummy.setEmpTag("DummyEmpTag");
empDummy.setEmpState("ACTIVE");
        
activeEmployeeList.add(empDummy);

or if you have all args constructor:

EmployeeBean empDummy = new EmployeeBean("00", "DummyEmp","DummyEmpTag","ACTIVE");

activeEmployeeList.add(empDummy);