I’ve got some compiler warnings of `Kotlin: Expected type does not accept nulls in Java, but the val...

# spring

[Michael]

I’ve got some compiler warnings of Kotlin: Expected type does not accept nulls in Java, but the value may be null in Kotlin around a MapSqlParameterSource("key", null) - but the value can be null, as far as I can tell.

[nfrankel]

you might be able to tell
but it seems the compiler cannot
perhaps you might have missed @NotNull annotations?

[todd.ginsberg]

I ran into this same thing. It appears that MapSqlParameterSource doesn't have its @Nullable annotation set properly. But if you think about it, the reason that class exists is because there's no elegant way to express Maps in Java. But in Kotlin we have mapOf("key" to null), which works as an argument to NamedParameterJdbcTemplate (assuming that's where you are using this).

[Michael]

Ahh, so I could build the map first, then construct the MapSqlParameterSource from it, rather than using the addValue on the MSPS. That makes sense!

[Michael]

(I’m actually using Spring Batch, not the template directly, so it I have to provide a setItemSqlParameterSourceProvider or a setItemPreparedStatementSetter. 📯