To simulate some auto-generated classes which looks like this, I made a small jUnit test class to simulate inheritance and hidden fields.
public class ClassDerivationTest {
@Test
public void testChild() {
ChildClass child = new ChildClass();
// Implicit boolean as it is hiding the super value
child.value = true;
// one way to update the parent value
// child.setParentVal("true");
// child.super.value = "test";
}
public class ChildClass extends ParentClass {
public boolean value;
}
public class ParentClass {
public String name;
public String value;
}
}
My question is: is there any short way to assign the super class value
field in a similar way like this:
child.super.value = "test";
instead than creating a specific setter in the ChildClass:
// Imagine this method is not existing for the question
public void setParentVal(String val) {
super.value = val;
}
I am using Java 7, and I am wondering if it would be possible without modifying the ChildClass
nor the ParentClass
(Like it could be auto-generated code).
UPDATE:
I know you there are several ways to manage this by
a) Casting according to Jon's answers: ((ParentClass) child).value = "test";
but not very well
b) Instanciate the super class like this (as much as possible): ParentClass myInstance = new ChildClass();
The code myInstance.value
will refer to the field in ParentClass
But I wanted to be more focused on the new features of Java 8. For example is it possible to resolve this with a lambda, or another new feature of Java 8?
Well you can just cast child
to make the compiler resolve the field value
with respect to ParentClass
instead of ChildClass
:
((ParentClass) child).value = "test";
But frankly I would a) avoid non-private fields; b) avoid knowingly giving superclasses and subclasses fields with the same name.
Contrary to your comment, the subclass field doesn't "override" the superclass field - it hides it.
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