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java - Overriding a super class's instance variables

Why are we not able to override an instance variable of a super class in a subclass?

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He perhaps meant to try and override the value used to initialize the variable. For example,

Instead of this (which is illegal)

public abstract class A {
    String help = "**no help defined -- somebody should change that***";
    // ...
}
// ...
public class B extends A {
    // ILLEGAL
    @Override
    String help = "some fancy help message for B";
    // ...
}

One should do

public abstract class A {
    public String getHelp() {
        return "**no help defined -- somebody should change that***";
    }
    // ...
}
// ...
public class B extends A {
    @Override
    public String getHelp() {
        return "some fancy help message for B";
    // ...
}

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