Some handy format combinations with Swagger:

type: string
format: byte

Creates a property of type byte[] (but it is serialized as a string).

type: integer
format: int64

Creates a property of type Long.

type: string
format: date-time

Creates a property of type OffsetDateTime (when using the java8 date library).

type: string
format: date

Creates a property of type LocalDate.