Abstract Class - Why is my protected method publicly accessible?

Question

Why can I access the doStuff() Method in the main method below? Since doStuff() is protected, I would expect that only TestClassImplementation has access to it.

public abstract class AbstractTestClass {
    protected void doStuff()
    {
        System.out.println("doing stuff ...");
    }
}

public class TestClassImplementation extends AbstractTestClass{

}

public class MyProgram {
    public static void main(String[] args) {
        TestClassImplementation test = new TestClassImplementation();
        test.doStuff(); //why can I access the doStuff() Method here?
    }
}

Answer 1

Looks like MyProgram class is in the same package of your AbstractTestClass. If so, then it can access to protected and public members of the classes in the same package.

Covered in Java tutorials:

Modifier    Class Package Subclass   World
public      Y     Y       Y          Y
protected   Y     Y       Y          N
no modifier Y     Y       N          N
private     Y     N       N          N

In order to fix this, just move the AbstractTestClass to another package. Similar for other relevant classes.

More info:

• Controlling Access to Members of a Class