什么是系统操作 口在SSD中定义了系统事件,而一个系统事件可以 通过一个系统操作来实现 口将所有用例的系统操作的完整集合封装到一个类 中,这个类定义了系统对外界的公共接口
什么是系统操作 在SSD中定义了系统事件，而一个系统事件可以 通过一个系统操作来实现。 将所有用例的系统操作的完整集合封装到一个类 中，这个类定义了系统对外界的公共接口
系统操作处理输入的系统事件 Process sale Scenario System Cashier makeNewsale0O… loop /[more items 1 enterltem(itemID, quantity) O these input system events evoke system operations the system event enterltem description, total invokes a system operation called enterltem and so forth endsaleo o-s is is the same as in object oriented programming when we say the message foo invokes the method(handling total with taxes operation) foo make Payment (amount change due, receipt
系统操作处理输入的系统事件 : Cashier enterItem(itemID, quantity) endSale() makePayment(amount) description, total total with taxes change due, receipt makeNewSale() these input system events invoke system operations the system event enterItem invokes a system operation called enterItem and so forth this is the same as in objectoriented programming when we say the message foo invokes the method (handling operation) foo loop [ more items ] :System Process Sale Scenario