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override and redifinition?  RSS feed

 
ge weipeng
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Posts: 2
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Hello, i just have a problem with the following code:
class Animal{
static void doStuff(){
System.out.print("a");
}
}
class Dog extends Animal{
static void doStuff(){
System.out.print("b");
}
public static void main(String [] args){
Animal [] a={new Animal(),new Dog(),new Animal()};
for(int x =0;x<a.length;x++)
a[x].doStuff();
}
}
They say that the method doStuff() in class Dog is not an override,but a redifinition.Why?What's the difference between them?
 
Marco Ehrentreich
best scout
Bartender
Posts: 1294
IntelliJ IDE Java Scala
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Hi!

Polymorphism (i.e. overriding methods) only works for non-static methods. Therefore the doStuff() in class dog is just shadowing the one from the base class because of the name clash but besides the two methods aren't related like overridden methods.

Have a look at this for an explanation of polymorphism ;-)

Marco
 
ge weipeng
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Thank you so much!
 
Marco Ehrentreich
best scout
Bartender
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IntelliJ IDE Java Scala
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You're welcome
 
Campbell Ritchie
Sheriff
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And welcome to JavaRanch
 
Consider Paul's rocket mass heater.
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