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  • Java Keyword -- super

    Reference: super

    When we override superclass's methods, but still want to invoke them, we can use keyword super in child classes. We can also use super to refer to a hidden field (although hiding fields is discouraged).

    // Superclass is parent class
    public class Superclass {
    
        public void printMethod() {
            System.out.println("Printed in Superclass.");
        }
    }
    
    // Subclass is child class
    public class Subclass extends Superclass {
    
        // overrides printMethod in Superclass
        public void printMethod() {
            super.printMethod();
            System.out.println("Printed in Subclass");
        }
        public static void main(String[] args) {
            Subclass s = new Subclass();
            s.printMethod();    
        }
    }

     Compiling and executing Subclass prints the following:

    Printed in Superclass.
    Printed in Subclass

    We can also use super() or super(parameter list) to invoke superclass's constructor.

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  • 原文地址:https://www.cnblogs.com/ireneyanglan/p/4834157.html
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