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javaobserver-pattern

Is it appropriate to use the Observer Pattern?

Support I have a Java Bean class that strictly holds instance fields:

class College 
{
     building = "Burruss";
     dean = "Mr. Bergess";
     schools[] String = {"College of Engineering", "Business School"};
     valedictorian = "Mr. Smart Guy";
     ...
     ...
     ...
}

Suppose that for every change in an instance of College, a message is sent:

class messageSender
{
       ... if (College values have changed)
              Send that instance's fields in byte[] form
}

Suppose that I have a Swing GUI (Java) that also checks for changes in College

class myGUI
{
      ... if (College values have changed)
              Alert each individual JTextField the updated field
}

Is the observer pattern relevant here? If college had 1000 variables, I would then have to include a "notifyObservers()" method for every time the instance fields values changes!

For example, for those 1000 variables, I have 1000 setter methods. Each setter method must then have a notifyObservers() call.

Is this right or is there a better way?

Solution

  • If you have a class with 1000 fields, you probably have other, more pertinent design problems.

    It is not abnormal for each of your field-altering methods (setters) to call notifyObservers(). You may want to try encapsulating as much state and logic as you can though; information hiding is just good design.