使用 Spring Data JPA 时无法提取 ResultSet

Question

I am trying to extract result set from my database using Spring Boot and Spring Data jpa. When I am applying jpa query I am getting the following error in my Postman application:

{
"timestamp": "2020-09-25T06:28:05.202+0000",
"status": 500,
"error": "Internal Server Error",
"message": "Parameter value element [{0=com.spacestudy.model.Users@2357844c}] did not match expected type [java.lang.Integer (n/a)]; nested exception is java.lang.IllegalArgumentException: Parameter value element [{0=com.spacestudy.model.Users@2357844c}] did not match expected type [java.lang.Integer (n/a)]",
"path": "/spacestudy/rockefeller/security/retrieveUserByNotRoleAssigned"
}

and in my STS editor console, I am getting the following message,

 java.lang.IllegalArgumentException: Parameter value element [{0=com.spacestudy.model.Users@2357844c}] did not match expected type [java.lang.Integer (n/a)

My repository UserRepository.java is codded like the following,

@Query("select new map(u.nuserId,u.susername) from Users u where u.nuserId NOT IN :userRoleMappingList")
List<Users> findByUsersNotassignedRole(@Param(value = "userRoleMappingList") List<Integer> userRoleMappingList);

And my service, I wrote like the following,

public List<Users> retrieveUsersByNotassignedRoles() {
    // TODO Auto-generated method stub
    
    List<Integer> userRoleMappingList = userRoleMappingRepoObj.findByUserId();
    
    return userRepoObj.findByUsersNotassignedRole(userRoleMappingList);
 }

and UserRoleMappingRepository.java coded with,

@Query("select new map(ur.nuserId) from UserRoleMapping ur")
List<Integer> findByUserId();

Where did I go in the wrong direction?

Answer 1

userRoleMappingList 应该是一个 userIds 列表。