Check if a object is a instance of a class (but not a instance of its subclass)

java instanceof
Addev picture Addev · May 22, 2013 · Viewed 43k times · Source

For this example:

public class Foo{}

public class Bar extends Foo{}

....

void myMethod(Foo qux){
   if (checkInstance(qux,Foo.class)){
     ....
   }
}

How can I check if qux is a instance of Foo (but not a instance of its subclass of foo)? That is:

  • checkInstance(qux,Foo.class)=true
  • checkInstance(qux,Bar.class)=false

Is there some kind of statement like instanceof for this check? or I should use qux.getClass().equals(Foo.class)

Answer

Duncan Jones picture Duncan Jones · May 22, 2013

If you have to do this, the only way would be the getClass().equals(Foo.class) option you've suggested.

However, the goal of OO design is to allow you to treat any Foo in the same fashion. Whether or not the instance is a subclass should be irrelevant in a normal program.

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