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java - How to override `toString()` properly to get rid of hash code

I'm retrieving test data from Room, but all I get is the hash-code data, even though I override the toString() method in my @Entity class. How do I know if the override method is used at all?

I have properly set up Room with a database, repository, viewModel and view using Live-data. From onCreate I have an observer that triggers correctly, and data is shown. As expected it is has-code data. Usually I turn this into string data by overriding toString() in the @Entity class and then using it in onCreate() but it doesn't work. It still gives me the hash data.

In my @Entity class I override toString() like this:

@Override
public String toString() {
    return "MyEntity{" +
            "id=" + id +
            ", title='" + title + ''' +
            ", description='" + description + ''' +
            ", priority=" + priority +
            '}';
}

And in my onCreate() I call the Interface using:

myViewModel.getAllData().observe( this, new Observer<List<MyEntity>>() {
        @Override
        public void onChanged(@Nullable List<MyEntity> myEntities) {

            Log.d("TAG: ", "DATA CHANGED! " + myViewModel.getAllData().toString());
        }
} );

But despite using .toString() I still just get the hash data:

D/TAG:: DATA CHANGED! android.arch.lifecycle.ComputableLiveData$1@a12e85e

I expect some basic test data:

"MY FIRST OBJECT", "THIS IS MY OBJECT", 1 
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1 Answer

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by (71.8m points)

You are calling toString() on ComputableLiveData, you have to call toString() on myEntities which will in turn call toString() on the individual elements which are MyEntity.

myViewModel.getAllData().observe( this, new Observer<List<MyEntity>>() {
    @Override
    public void onChanged(@Nullable List<MyEntity> myEntities) {
        Log.d("TAG: ", "DATA CHANGED! " + myEntities.toString());
    }
});

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