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Java

Posted by Javique Ryan
Javique Ryan
Courses Plus Student 2,405 Points

Variables in classes as private or public

In java , Should I declare all my variable in my classes as private or public ?

brendon hanson
brendon hanson
6,191 Points

It depends, however it's usually good practice to make them private. I'm not all that smart in java though so maybe someone else will have a better answer.

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The common convention is to declare them as private, and then add getter/setter methods based on how you want them to be accessed. It is an example of Encapsulation which is often considered a fundamental part of object oriented programming.

By making your fields private and using getter/setter method to make them available outside the class you get a lot more control over what happens when they are accessed and how they are changed. Which allows you to make assumptions about the state of the field variables in your own code that would be unsafe to make if those variables could be changed from external code whenever and to whatever the external code wanted.