Packages

class whenAbsent[+T] extends Annotation with StaticAnnotation

An alternative way to provide default value for case class parameter used during deserialization with GenCodec when its field is missing in data being deserialized. Normally, Scala-level default parameter values are picked up, but you may want to use this annotation instead if you don't want to pollute your Scala classes with unintended default parameter values (i.e. you want a default value *only* for deserialization).

case class HasDefault(@whenAbsent("default") str: String)
object HasDefault extends HasGenCodec[HasDefault]

If a parameter has both Scala-level default value and is annotated with @whenAbsent then value from annotation takes priority. You can use this to have different source-level default value and different default value for deserialization. You can also leverage this to "remove" default value for deserialization:

case class HasNoDefault(@whenAbsent(throw new Exception) str: String = "default")
object HasDefault extends HasGenCodec[HasDefault]

NOTE: whenAbsent also works for method parameters in RPC framework.

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StaticAnnotation, Annotation, AnyRef, Any
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Instance Constructors

  1. new whenAbsent(v: ⇒ T)

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  5. def clone(): AnyRef
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  6. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  7. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  8. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  9. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  10. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  12. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  13. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  14. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  15. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  16. def toString(): String
    Definition Classes
    AnyRef → Any
  17. def value: T
  18. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  19. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  20. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )

Inherited from StaticAnnotation

Inherited from Annotation

Inherited from AnyRef

Inherited from Any

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