#java encapsulation

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In part one I introduced the concept of setter and getter methods, these methods are also known as mutator (setter) and accessor (getter) methods. Also in part one I left you hanging on how we can prevent the direct usage of our instance variables. We can control the access to our instance variables using access modifiers. The topic of access modifiers is quite extensive and there are many rules that are way beyond the scope of this tutorial. I will be covering them in detail in future tutorials, but for now I will introduce you to the access modifier private and how it affects instance variables. The access modifier private must be placed before the type when declaring an instance variable.

This is part one of a two part tutorial on the concept of encapsulation. It is almost impossible to explain the concept of encapsulation with just wording alone. You must first understand the problem that encapsulation resolves. By the end of part two, you should have a good grasp of what encapsulation is. An instance variable is a variable declared in a class that has a separate copy (value) for each object created. In my Instance Variable Tutorial, we saw how we could directly set the values of the instance variables for each object we created. Now what do we do if we want to control what values can be stored in an instance variable? We can use a setter method to set the value of an instance variable. We can get the value of an instance variable by using a getter method. Becoming familiar with getter and setter methods is key to understanding the concept of encapsulation.