akka.util

Class Helpers.Requiring<A>

java.lang.Object

scala.AnyVal

akka.util.Helpers.Requiring<A>

Enclosing class:

Helpers

public static final class Helpers.Requiring<A>
extends scala.AnyVal

Implicit class providing requiring methods. This class is based on Predef.ensuring in the Scala standard library. The difference is that this class's methods throw IllegalArgumentExceptions rather than AssertionErrors.

An example adapted from Predef's documentation:

 import akka.util.Helpers.Requiring

 def addNaturals(nats: List[Int]): Int = {
   require(nats forall (_ >= 0), "List contains negative numbers")
   nats.foldLeft(0)(_ + _)
 } requiring(_ >= 0)
 

param: value The value to check.

Constructor Summary

Constructors

Constructor and Description
Requiring(A value)

Method Summary

Modifier and Type	Method and Description
A	requiring(boolean cond, scala.Function0<java.lang.Object> msg) Check that a condition is true.
A	requiring(scala.Function1<A,java.lang.Object> cond, scala.Function0<java.lang.Object> msg) Check that a condition is true for the value.
A	value()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Requiring

public Requiring(A value)

Method Detail

value

public A value()

requiring

public A requiring(boolean cond,
                   scala.Function0<java.lang.Object> msg)

Check that a condition is true. If true, return value, otherwise throw an IllegalArgumentException with the given message.

Parameters:

cond - The condition to check.

msg - The message to report if the condition isn't met.

Returns:

(undocumented)

requiring

public A requiring(scala.Function1<A,java.lang.Object> cond,
                   scala.Function0<java.lang.Object> msg)

Check that a condition is true for the value. If true, return value, otherwise throw an IllegalArgumentException with the given message.

Parameters:

cond - The function used to check the value.

msg - The message to report if the condition isn't met.

Returns:

(undocumented)