CODEWITHSUNDEEP
javarestjpaspring-bootspring-rest
Anil Bhaskar
Anil Bhaskar

Reputation: 3978

Error: The given id must not be null for GeneratedValue in JPA

My object:

@Entity
@Table(name="user")
public class User {
    @Id
    @Column(name="uid")
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private Long id;

  //more code
 }

When I POST user JSON without uid, I am getting error as the given id must not be null. Which should not be the case while uid should be generated by the database. Please point what am I missing.

JSON:

{
"email": "[email protected]",
"name": "John Doe",
"phone": "98-765-4445"
}

Error:

{
"timestamp": 1501058952038,
"status": 500,
"error": "Internal Server Error",
"exception": "org.springframework.dao.InvalidDataAccessApiUsageException",
"message": "The given id must not be null!; nested exception is java.lang.IllegalArgumentException: The given id must not be null!",
"path": "/api/user/"
}

Upvotes: 9

Views: 70001

Answers (4)

Mukti Barakoti
Mukti Barakoti

Reputation: 11

Same issue encountered with findById() method while I was missing @PathVariable(value="id") ID id in getIdSpecificResult() method. This was a minor missing piece on my code. Reasons could be any though.

Upvotes: 0

Axman
Axman

Reputation: 11

Nothing is wrong WHETHER you do @GeneratedValue(strategy=GenerationType.IDENTITY) or @GeneratedValue(strategy=GenerationType.TABLE) in this particular problem. Any strategy works. ALL you have make sure is @PathVariable is used or not when you are passing id.

Upvotes: 1

Anil Bhaskar
Anil Bhaskar

Reputation: 3978

It was my bad, I was calling foo(user.getId()) before saving the User object into the database. Takeaways from this: @GeneratedValue(strategy=GenerationType.IDENTITY) is the correct code and generates identical ids while saving to database1. And Long is not a problem. Thanks.

[1]: I am saving the object into the database by, something like: userRepository.save(user).

Upvotes: 15

Mustafa
Mustafa

Reputation: 6154

To generate string uuid's for primary keys (as I assume you are trying to do) you can try the following code:

@Id
@GeneratedValue(generator = "uuid")
@GenericGenerator(name = "uuid", strategy = "uuid2")
private String id;

Upvotes: 0

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