Address book

{jet}
namespace addressbook

class Contact(
val name : String,
val emails : List<EmailAddress>,
val addresses : List<PostalAddress>,
val phonenums : List<PhoneNumber>
)

class EmailAddress(
val user : String,
val host : String
)

class PostalAddress(
val streetAddress : String,
val city : String,
val zip : String,
val state : USState?,
val country : Country
) {
assert {(state == null) xor (country == Countries["US"]) }
}

class PhoneNumber(

object Countries {
fun get(id : CountryID) : Country = countryTable[id]

private var table : Map<String, Country>? = null
private val countryTable : Map<String, Country>
get() {
if (table == null) {
table = HashMap()
for (line in TextFile("countries.txt").lines(stripWhiteSpace = true)) {
table[line] = Country(line)
}
}
return table
}
}

class Country(val name : String)
{jet}

h3. What's next

* [HTML builder example|Type-safe Groovy-style builders]