我有以下实体：

@Entity
@Data
@IdClass(ProjectEmployeeId.class)
public class ProjectEmployee {

  @Id
  @ManyToOne
  private Project project;

  @Id
  @ManyToOne
  private Employee employee;

  @ManyToOne
  private ProjectEmployeeRole projectEmployeeRole;
}

id类定义了上述实体的复合主键：

@Data
public class ProjectEmployeeId implements Serializable {
  private Project project;

  private Employee employee;
}

这就是repository：

public interface ProjectEmployeeRepository
        extends CrudRepository<ProjectEmployee, ProjectEmployeeId> {
}

我试图保存一个项目Employee：

projectEmployeeRepository.save(projectEmployee);

这给了我以下错误：

Resolved [org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.lang.Long' to required type 'de.employee.Employee' for property 'employee'; nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.lang.Long' to required type 'de.employee.Employee' for property 'employee': no matching editors or conversion strategy found]

我第一次使用复合主键，所以我不知道它应该如何工作。问题可能来自于定义CrudRepository<ProjectEmployee, ProjectEmployeeId>。第二个参数应该表示id。但是ProjetEmployee没有一个主键，而是有两个，所以我想我应该把id类添加到id参数中，这是不起作用的。如何使用CrudRepository中的IdClass键保存具有复合主属性的实体？