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In (multithreaded) object-oriented programming, asynchronous method invocation (AMI), also known as asynchronous method calls or asynchronous pattern is a client-side support that doesn't block the calling thread while waiting for a reply. Instead, the calling thread is notified when the reply arrives. Polling for a reply is an undesired option. == Background == AMI is a design pattern for asynchronous invocation of potentially long-running methods of an object. It is equivalent to the IOU pattern described in 1996 by Allan Vermeulen. In most programming languages a called method is executed synchronously, i.e. in the thread of execution from which it is invoked. If the method needs a long time to completion, e.g. because it is loading data over the internet, the calling thread is blocked until the method has finished. When this is not desired, it is possible to start a "worker thread" and invoke the method from there. In most programming environments this requires many lines of code, especially if care is taken to avoid the overhead that may be caused by creating many threads. AMI solves this problem in that it augments a potentially long-running ("synchronous") object method with an "asynchronous" variant that returns immediately, along with additional methods that make it easy to receive notification of completion, or to wait for completion at a later time. One common use of AMI is in the active object design pattern. Alternatives are synchronous method invocation and future objects. An example for an application that may make use of AMI is a web browser that needs to display a web page even before all images are loaded. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Asynchronous method invocation」の詳細全文を読む スポンサード リンク
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