JPA query couldn't find the right constructor-CodePudding

So basically I try to get some data of a User by its ID and it has a field with @OneToOne relationship(bidirectional)

When I try to create a query in JpaRepository with @Query annotation

@Query("SELECT new com.project.model.user(u.id, u.username, u.profile.last_online, u.profile.about) FROM User u WHERE id = :id)

and a constructor

User(long id, long username, Profile profile) {
   this.id = id;
   this.username = username;
   this.profile = profile;
}

it still can't really find the constructor and says that there is no "matching constructor", is there a way to create the constructor better?

CodePudding user response：

The constructor you expect in your query has (long, String, Timestamp, String). And your constructor takes (long, long, Profile).

So you need to create a matching constructor:

public User(long id, String username, Timestamp lastOnline, String about) {
    this.id = id;
    this.username = username;
    this.profile = new Profile(lastOnline, about); // create new Profile with lastOnline & about
}

This should work.

But may I ask why you're not using the JpaRepository#findById(Long id) method?