SOFTWARE DESIGN
DESIGN PATTERNS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Bridge
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Mediator
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Observer
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Adapter
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Detailed explanation-1: -The observer pattern defines a one-to-many dependency between objects so that when one object changes state, all of its dependents are notified and updated automatically. The object which is being watched is called the subject. The objects which are watching the state changes are called observers or listeners.
Detailed explanation-2: -Observer pattern is used when there is one-to-many relationship between objects such as if one object is modified, its depenedent objects are to be notified automatically. Observer pattern falls under behavioral pattern category.
Detailed explanation-3: -Observer design pattern is useful when you are interested in the state of an object and want to get notified whenever there is any change. In observer pattern, the object that watch on the state of another object are called Observer and the object that is being watched is called Subject.