Map instances returned by JpaRepository queries do not handle null map values correctly [DATAJPA-1301]

[spring-projects-issues]

John Mann opened DATAJPA-1301 and commented

Given the JpARepository:

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.stereotype.Repository;

import java.util.Map;

@Repository
interface MyEntityJpaRepo extends JpaRepository<MyEntity, String> {

    @Query("SELECT t.id as id, t.foo as foo, t.bar as bar FROM MyEntity t WHERE t.id = ?1")
    Map findSomething(String id);

}

And table data:

id	foo	bar
"1"	"x"	null

The Map instance returned does not behave correctly.

// Pseudocode
Map map = myEntityJpaRepo.findSomething("1");

// the following are true
map == { "id": "1", "foo": "x", "bar": null }
map.keySet() == { "id", "foo", "bar" }


map.get("id").equals("1")   // true
map.get("foo").equals("x")  // true
map.get("bar") == null      // true

map.containsKey("id") == true
map.keySet().contains("id") == true
map.containsKey("foo") == true
map.keySet().contains("foo") == true

// the following should be true, but are false
map.containsKey("bar") == true
map.keySet().contains("bar") == true

It looks like containsKey method is not implemented correctly on AbstractJpaQuery

---

Affects: 2.1 M1 (Lovelace), 1.11.10 (Ingalls SR10), 2.0.5 (Kay SR5)

Referenced from: pull request #262

Backported to: 2.0.6 (Kay SR6), 1.11.11 (Ingalls SR11)

[spring-projects-issues]

Oliver Drotbohm commented

I am not sure we can actually completely fix this due to Hibernate's refined alias handling being aligned with SQL which assumes all caps aliases by default. Depending on the database you're using you can explicitly quote the aliases in the query which should make them appear in exactly the case you defined it.

Jens Schauder – Would you mind having a look at this? Maybe we can tweak the implementation slightly?

[spring-projects-issues]

Oliver Drotbohm commented

That's polished, merged and backported into Kay and Ingalls. Feel free to give the snapshots a try

[spring-projects-issues]

John Mann commented

This is still broken in 2.0.1.BUILD-SNAPSHOT. The containsKey method is still returning false for map entries with null values

[spring-projects-issues]

Oliver Drotbohm commented

That's expected as 2.0.5.BUILD-SNAPSHOT is the version that the fix was applied to. Looks like you mix up Spring Boot versions with Spring Data ones?

[spring-projects-issues]

John Mann commented

Ah, crap. I'm sorry. I will retest with the correct version