Hành động nhập Một hành động nhập cảnh là một hành vi xảy ra trong khi đối tượng được chuyển vào nhà nước. Sử dụng ví dụ chuyến bay của chúng tôi, ngay sau khi một chuyến bay trở thành kế hoạch, hệ thống tiến độ Internet. Điều này xảy ra trong khi máy bay được chuyển vào tình trạng theo lịch trình. | Chapter 9 Object Behavior Activity An activity is some behavior that an object carries out while it is in a particular state. For example when an account is in the Closed state the account holder s signature card is pulled. When a flight is in a Canceled state the airline tries to find alternate flights for its customers. An activity is an interruptible behavior. It may run to completion while the object is in that state or it may be interrupted by the object moving to another state. An activity is shown inside the state itself preceded by the word do and a slash. Canceled do Arrange alternate flight for customers Entry Action An entry action is a behavior that occurs while the object is transitioning into the state. Using our flight example as soon as a flight becomes scheduled the system posts the schedule to the Internet. This happens while the flight is transitioning into the Scheduled state. Unlike an activity an entry action is considered to be noninterruptible. While the posting of a schedule record for use on the Internet is technically interruptible it happens very fast and the user does not have the ability to easily cancel the transaction while it is occurring. Therefore it can be modeled as an action. There is a fine line between an action and an activity but the distinguishing characteristic is whether or not it is interruptible. An entry action is shown inside the state preceded by the word entry and a slash. Scheduled entry Post flight schedule on Internet do Check current date Exit Action An exit action is similar to an entry action. However an exit action occurs as part of the transition out of a state. For example when the plane lands and transitions out of the In Flight state the system records the landing time. Like an entry action an exit action is considered to be noninterruptible. An exit action is shown inside the state preceded by the word exit and a slash. In Flight exit Record landing time The behavior in an activity entry action or exit
