Cannot auto upgrade a database with a non null value

[ksdc-anandhid]

I have an Android class with the following fields:

public class Player {
    @Id
    private long id;
    private String name;
    private int  jerseyNumber;
}

The above code works fine.
For the auto-upgrade, I add a new non-null property named code like the following:

public class Player {
    @Id
    private long id;
    private String name;
    private int jerseyNumber;
    @Nonnull
    private String code;
}

There is a null pointer exception as the database is trying to be upgraded as Objectbox was not able to insert a non-null code for the existing rows.

Please advise on a solution.

[greenrobot-team]

ObjectBox ignores @Nonnull annotations. How does the constructor or the setter look like? Does it do a null check?

Could you provide the stack trace of the crash?

[ksdc-anandhid]

I use Lombok and so my code looks like the below

@DaTa
@NoArgsConstructor
@AllArgsConstructor

@entity
public class Player {
@id
private long id;
private String name;
private int jerseyNumber;
@nonnull
private String code;
}

2020-02-03 15:01:25.593 30716-30716/com.example.objectboxdemo E/Box: Entity creation failed
2020-02-03 15:01:25.672 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] JNI DETECTED ERROR IN APPLICATION: JNI CallBooleanMethodV called with pending exception java.lang.NullPointerException: code is marked non-null but is null
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at void com.example.objectboxdemo.model.Player.(long, java.lang.String, int, java.lang.String) (Player.java:19)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.util.List io.objectbox.query.Query.nativeFind(long, long, long, long) (Query.java:-2)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.util.List io.objectbox.query.Query$3.call() (Query.java:209)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.lang.Object io.objectbox.query.Query$3.call() (Query.java:206)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.lang.Object io.objectbox.BoxStore.callInReadTx(java.util.concurrent.Callable) (BoxStore.java:759)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.lang.Object io.objectbox.BoxStore.callInReadTxWithRetry(java.util.concurrent.Callable, int, int, boolean) (BoxStore.java:704)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.lang.Object io.objectbox.query.Query.callInReadTx(java.util.concurrent.Callable) (Query.java:293)
2020-02-03 15:01:25.673 30716-30716/com.example.objectboxdemo A/zygote64: java_vm_ext.cc:534] at java.util.List io.objectbox.query.Query.find() (Query.java:206)

[greenrobot-team]

Looks like the constructor generated by your tooling does do a null check. However, ObjectBox will pass null as that's what is in the database for code of existing entities: nothing.

Two options:

• run some upgrade code which explicitly stores a default value, or
• ensure the constructor can be called with a null value for code.

As for ObjectBox supporting default values look at #157.

[ksdc-anandhid]

Hi,
I used the option 2 and added a not null constructor. It works fine.