Stop your services gracefully in Scala with tryAll

	object ErrorUtils{
	/**
	* Executes a block and returns the result wrapped by Right class, or exception wrapped by Left class.
	*/
	def either[T](block:() => T) : Either[Throwable,T] = try {Right(block())} catch {case e => Left(e)}
	/**
	* Executes all blocks in order and collects exceptions. It guarantees to execute all blocks, even if some of them fail.
	* It throws a BlockException, if any number of blocks fail. BlockException contains a list of thrown exceptions.
	*
	* <br/><br/>Example:
	<pre>
	tryAll(
	service1.stop,
	service2.shutdown,
	service3.kill
	)
	</pre>
	*
	* @return nothing
	* @throws BlockException if any number of blocks fail. BlockException contains a list of thrown exceptions.
	*
	*/
	def tryAll(block1 : => Unit, block2 : => Unit = {}, block3 : => Unit= {}, block4 : => Unit = {}, block5 : => Unit = {}, block6 : => Unit = {}) = {
	val blocks = List(()=>block1, ()=>block2, ()=>block3, ()=>block4, ()=>block5, ()=>block6)
	val errors = blocks.toList.map(either(_)).filter(_.isLeft).map{case Left(e) => e}
	if (!errors.isEmpty) throw new BlockException(errors)
	}
	case class BlockException(errors : List[Throwable]) extends RuntimeException("There were errors while executing blocks: "+errors)
	}

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