From 98e2821b38a775737e42a2479a6bc65107210859 Mon Sep 17 00:00:00 2001 From: Elliot Kroo Date: Thu, 11 Mar 2010 15:21:30 -0800 Subject: reorganizing the first level of folders (trunk/branch folders are not the git way :) --- infrastructure/net.appjet.oui/dynamicvar.scala | 49 ++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 infrastructure/net.appjet.oui/dynamicvar.scala (limited to 'infrastructure/net.appjet.oui/dynamicvar.scala') diff --git a/infrastructure/net.appjet.oui/dynamicvar.scala b/infrastructure/net.appjet.oui/dynamicvar.scala new file mode 100644 index 0000000..b1f8c2e --- /dev/null +++ b/infrastructure/net.appjet.oui/dynamicvar.scala @@ -0,0 +1,49 @@ +/** + * Copyright 2009 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS-IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package net.appjet.oui; + +class NoninheritedDynamicVariable[T](init: T) { + private val tl = new ThreadLocal[T] { + override def initialValue = init.asInstanceOf[T with AnyRef] + } + + /** Retrieve the current value */ + def value: T = tl.get.asInstanceOf[T] + + + /** Set the value of the variable while executing the specified + * thunk. + * + * @param newval The value to which to set the fluid + * @param thunk The code to evaluate under the new setting + */ + def withValue[S](newval: T)(thunk: =>S): S = { + val oldval = value + tl.set(newval) + + try { thunk } finally { + tl.set(oldval) + } + } + + /** Change the currently bound value, discarding the old value. + * Usually withValue() gives better semantics. + */ + def value_=(newval: T) = { tl.set(newval) } + + override def toString: String = "NoninheritedDynamicVariable(" + value +")" +} -- cgit v1.2.3-1-g7c22