////////////////////////////////////////////////////////////////////////////////
//
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You 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 mx.core
{
/**
* A deferred instance factory that creates and returns an instance
* of a specified class.
* An application can use the getInstance()
method to
* create an instance of the class when it is first needed and get
* a reference to the instance thereafter.
*
* @see DeferredInstanceFromFunction
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public class DeferredInstanceFromClass implements ITransientDeferredInstance
{
include "../core/Version.as";
//--------------------------------------------------------------------------
//
// Constructor
//
//--------------------------------------------------------------------------
/**
* Constructor.
*
* @param generator The class whose instance the getInstance()
* method creates and returns.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public function DeferredInstanceFromClass(generator:Class)
{
super();
this.generator = generator;
}
//--------------------------------------------------------------------------
//
// Variables
//
//--------------------------------------------------------------------------
/**
* @private
* The generator class.
*/
private var generator:Class;
/**
* @private
* The generated value.
*/
private var instance:Object = null;
//--------------------------------------------------------------------------
//
// Methods
//
//--------------------------------------------------------------------------
/**
* Creates and returns an instance of the class specified in the
* DeferredInstanceFromClass constructor, if it does not yet exist;
* otherwise, returns the already-created class instance.
*
* @return An instance of the class specified in the
* DeferredInstanceFromClass constructor.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public function getInstance():Object
{
if (!instance)
instance = new generator();
return instance;
}
/**
* Resets the state of our factory to the initial, uninitialized state.
* The reference to our cached instance is cleared.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 4
*/
public function reset():void
{
instance = null;
}
}
}