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The balking pattern is a software design pattern that only executes an action on an object when the object is in a particular state. For example, if an object reads ZIP files and a calling method invokes a get method on the object when the ZIP file is not open, the object would "balk" at the request. In the Java programming language, for example, an IllegalStateException might be thrown under these circumstances. There are some specialists in this field who think this is more of an anti-pattern, than a design pattern. If an object cannot support its API, it should either limit the API so that the offending call is not available, or so that the call can be made without limitation it should: * Be created in a "sane state" * Not make itself available until it is in a sane state * Become a facade and answer back an object that is in a sane state ==Usage== Objects that use this pattern are generally only in a state that is prone to balking temporarily but for an unknown amount of time. If objects are to remain in a state which is prone to balking for a known, finite period of time, then the guarded suspension pattern may be preferred. 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「balking pattern」の詳細全文を読む スポンサード リンク
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