There are many articles out there dealing of with the accessor and mutator methods (getters and setters). They came together with the Object-Oriented principles. Information hiding says that the internal state of an object must be hidden from the outer world. That is, the fields it uses shouldn't be available. Yet, sometimes we have to query the state of the object, and even may want to change that state. Directly accessing the field representing the state is considered to be a bad practice (the field shouldn't be available), therefore a method must be provided to retrieve the value of the field. This method is the accessor method (the getter). Similarly, a method might be provided to change the value of the corresponding field. This method is the mutator method (the setter). Usually, the signature of these methods follow the <Type> get<FieldName>() and void set<FieldName>(<Type> newValue) notation. So we are safe, we strictly follow the OO principles, right?
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