Java 如何将HashMap添加到Employee类的列表中

我创建了一个Java类，并使用JPA检索Employee类的详细信息，该类将返回一个类似

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

在收到散列列表后，我想添加几个伪条目，如

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

所以我试图将映射添加到员工列表中，但在运行时我得到了

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

我的员工类别：

@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) 
}

存储库：-

public interface EmployeeBeanRepository extends JpaRepository<EmployeeBean, String>{

    List < EmployeeBean > findByEmpState(String empState);

public接口EmployeeBeanRepository扩展了JpaRepository{
ListfindByEmpState（字符串状态）；

资源：-

@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;
    }
}

@RestController
@请求映射（“/empDetails”）
公共类EmployeeBeanResource{
私人最终雇员为雇员；
公共员工资源（员工资源）{
this.empBeanRepository=empBeanRepository；
}
@GetMapping（“/empState/{empState}”）
@定时
公共列表getEmployeesByStatus（@PathVariable String-empState）{
List-activeEmployeeList=empBeanRepository.findByEmpState（empState）；
Map empmdummy=newhashmap（）；
empId.put（“empId”，“00”）；
empDummy.put（“empName”、“DummyEmp”）；
EMPSDUMMY.put（“空包”、“空包”）；
empsdummy.put（“empState”、“ACTIVE”）；
add（（EmployeeBean）empDummy.keySet（））；
add（（EmployeeBean）empDummy.values（））；
返回activeEmployeeList；
}
}

我已经尝试了很多，但仍然无法找到将映射添加到员工列表中的方法。

而不是：

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());

或者，如果您拥有所有参数构造函数：

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

activeEmployeeList.add(empDummy);

---

您应该创建

EmployeeBean

，然后添加到

activeEmployeeList

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

activeEmployeeList.add(empDummy);