JSON4S Extensions

JSON4S Extensions is a small collection of serializers, formatters and other useful extensions for JSON4S in Scala.

ExtendedFormats

The ExtendedFormats object (and trait) works in exactly the same way as JSON4S DefaultFormats, but with a few other useful serializers included by default.

package mypackage

import com.adlawson.json4s.ExtendedFormats
import org.json4s.native.Serializer.{read, write}

implicit val formats = ExtendedFormats

val foo = read[Foo](someJsonString)
val raw = write(foo)

Included in ExtendedFormats are the following serializers

CharSerializer for [de]serializing Char field types
TypeFieldSerializer for mapping a JSON type field to typ in a class

TypeSerializer

The abstract TypeSerializer can be used to create custom serializers for complex types, including types with mixins and matching trait implementations.

package mypackage

import com.adlawson.json4s.TypeSerializer
import org.json4s.DefaultFormats

type FooBar = Foo with Bar

case class Foo(a: Int)
trait Bar { def b: Int }

private[mypackage] case class _FooBar(a: Int, b: Int)

object FooBarSerializer extends TypeSerializer[FooBar, _FooBar] {
  override def wrap(f: FooBar) = _FooBar(f.a, f.b)
  override def unwrap(f: _FooBar) = new Foo(f.a) with Bar { val b = f.b }
}

implicit val format = DefaultFormats + FooBarSerializer

val fbar = read[FooBar]("""{"a":1,"b":2}""")
val json = write(fbar)

Examples

For further use cases and working examples of the different library components, please see the bundled examples.

Contributing

Contributions are accepted via Pull Request, but passing unit tests must be included before it will be considered for merge.

License

The content of this library is released under the MIT License by Andrew Lawson.
You can find a copy of this license in LICENSE or at http://opensource.org/licenses/mit.

adlawson / scala-json4s