Actually it's about `preZone` and `postZone` which are `DateTimeZone`. IMHO, using `boolean` makes code more readable with a cost of two booleans.

If I don't use boolean, it ends up with a lot of if conditions when parsing. Or I'm missing something.

Without booleans, I can catch when a user tries to set:

```
"time_zone": "+1",
"pre_zone":"+1"
```

but it's harder to catch:

```
"pre_zone":"+1",
"time_zone": "+1"
```

Or I need to define a `DateTimeZone timeZone = null;` and at the end compare...

What option do you prefer? A new timeZone field, booleans, or another suggestion?