JPA Query - no appropriate constructor in class error-CodePudding

I have an Employee entity class that has many columns. I want to get some columns from this class, therefore I have used dtos. I created a new BaseEmployee class and writed query in EmployeeRepository. But I get this error: "no appropriate constructor in class error" when I try to run app.

@Entity
@Table(name = "employees")
@Data
@AllArgsConstructor
@NoArgsConstructor
@JsonAutoDetect(fieldVisibility = Visibility.ANY)
public class Employee {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "emp_no")
    private  int id;
    @Column(name = "birth_date")   
    private Date birthDate;
    @Column(name = "first_name")
    private String firstName;
    @Column(name = "last_name")
    private String lastName;
    @Column(name = "gender")
    private char gender;
    @Column(name = "hire_date")  
    private Date hireDate;

    @OneToMany(mappedBy = "employees")
    private List<Title> titles; 

    @OneToMany(mappedBy = "employees")
    private List<Salary> salary;

    @OneToMany(mappedBy = "employee")
    private List<DeptEmp> departmentList;

   @OneToMany(mappedBy = "employee")
   private List<DeptManager> managerDepartment;

}

My dto class:

@Data
@NoArgsConstructor
@AllArgsConstructor
public class BaseEmployee {

    private  int id;
    private Date birthDate;
    private String firstName;
    private String lastName;
    private char gender;
    private Date hireDate;

}

Jpa Repository:

public interface EmployeeRepository extends JpaRepository<Employee,Integer> {
    
    List<Employee> getByFirstNameContains(String firstName);
    List<Employee> getByFirstNameStartsWith(String firstName);


    @Query("Select new dev.serhat.employeeapi.models.dtos.BaseEmployee"
      "(e.id, e.birthDate, e.firstName, e.lastName, e.gender, e.hireDate) From Employee e WHERE e.id = :id")
    Optional<BaseEmployee> getBaseEmployeeById(int id);
    
    
}

Errors:

HH000400: Using dialect: org.hibernate.dialect.MySQL5InnoDBDialect
2022-02-20 16:33:42.533  INFO 24371 --- [  restartedMain] o.h.e.t.j.p.i.JtaPlatformInitiator       : HHH000490: Using JtaPlatform implementation: [org.hibernate.engine.transaction.jta.platform.internal.NoJtaPlatform]
2022-02-20 16:33:42.559  INFO 24371 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
2022-02-20 16:33:43.431 ERROR 24371 --- [  restartedMain] o.h.hql.internal.ast.ErrorTracker        :  Unable to locate appropriate constructor on class [dev.serhat.employeeapi.models.dtos.BaseEmployee]. Expected arguments are: int, java.util.Date, java.lang.String, java.lang.String, char, java.util.Date
[cause=org.hibernate.PropertyNotFoundException: no appropriate constructor in class: dev.serhat.employeeapi.models.dtos.BaseEmployee]
2022-02-20 16:33:43.443 ERROR 24371 --- [  restartedMain] o.h.hql.internal.ast.ErrorTracker        :  Unable to locate appropriate constructor on class [dev.serhat.employeeapi.models.dtos.BaseEmployee]. Expected arguments are: int, java.util.Date, java.lang.String, java.lang.String, char, java.util.Date
[cause=org.hibernate.PropertyNotFoundException: no appropriate constructor in class: dev.serhat.employeeapi.models.dtos.BaseEmployee]

org.hibernate.hql.internal.ast.DetailedSemanticException: Unable to locate appropriate constructor on class [dev.serhat.employeeapi.models.dtos.BaseEmployee]. Expected arguments are: int, java.util.Date, java.lang.String, java.lang.String, char, java.util.Date
        at org.hibernate.hql.internal.ast.tree.ConstructorNode.resolveConstructor(ConstructorNode.java:182) ~[hibernate-core-5.6.4.Final.jar:5.6.4.Final]

CodePudding user response：

The error is quite straightforward, your class BaseEmployee lacks the appropriate constructor needed to execute getBaseEmployeeById(). Your class is annotated with @NoArgsConstructor and @AllArgsConstructor but those are lombok annotations that may not be recognized by Spring. Your method getBaseEmployeeById() needs an explicitly defined constructor with the following signature:

public BaseEmployee(int id, Date birthDate, String firstName, String lastName, char gender, Date hireDate)

Such a constructor is currently missing.

Please add a constructor with the described signature to your class and try again.

CodePudding user response：

We can't see the imports in these classes. Are the same Date types imported in both BaseEmployee and Employee? If one has java.util.Date and the other has java.sql.Date, then that would explain the missing constructor.