Question

It is said that the following code violates the OO Guiding Principle.

public class Main {
   public static String NAME = "James";

   public Main() {
      System.out.println("Name is: "+NAME);
   }
}

public class AnotherMain() {
   public AnotherMain() {
      System.out.println("Print name: "+Main.NAME);
   }
}

All I could guess is it could have an abstract class that has a concrete method of say print(String message) and then have the Main class and AnotherMain class to extend the abstract class and then pass their to-be-printed message into the print() method implemented in their parent abstract class. Then in their constructors, they would call print(“Name is: “+NAME). This would save the constructors from calling System.out.println() twice.

But I am still sceptical because it says that the code has something that violates the OO Guiding Principle.

Any suggestions for this?
Thanks.

Answer 1

Right off the top of my head,

System.out.println("Print name: "+Main.NAME);

violates encapsulation by accessing something owned by an independent class; if that is intended, then NAME should be independent of both classes and imported into both their scopes.