Re: Distinguish null vs unspecified value in java

[Sid Golestane]

I managed to implement this using the union type which I didn't know
about until a couple of days ago.

Here is a snippet in case someone else had the same use case.

union NullableString {
  1: bool isNull,
  2: string value,
}

struct Account {
    1: i64 id,
    2: string username,
    3: required string password,
    4: optional NullableString name,
}

Using NullableString I can distinguish between missing and null strings:

if (account.getName() == null) {
    // name field is not set
} else {
    if (account.getName().getSetField() == NullableString._Fields.IS_NULL) {
        // name field is set to NULL
    } else {
        // name is set to account.getName().getValue()
    }
}

-Sid