What is the easiest way to do 'is' in Java?
Many languages have a facility to check to see if an Object is of a certain type (including parent subclasses), implemented with 'is' and used like this:
if(obj is MyType)
Or slightly more tediously you can in other languages check by using the 'as' keyword to do a soft typecast and seeing if the result null.
I haven't used Java in years and I'm getting back up to speed on it but surely Java has a way to easily do this without delving deep into the Reflection APIs?
Thanks in advance for answers. I have searched both here and other places but the keywords involved are so generic that even though I'm sure this has a simple answer, googling for it is hard.
Asked by: Ada614 | Posted: 28-01-2022
Answer 1
if (objectReference instanceof type){
//Your code goes here
}
More info here.
Answered by: Brianna565 | Posted: 01-03-2022Answer 2
You can only use instanceof with a class literal: that is:
Class type = String.class;
if (myObj instanceof String) // will compile
if (myObj instanceof type) //will not compile
The alternative is to use the method Class.isInstance
if (type.isInstance(myObj)) // will compile
Answer 3
obj instanceof TargetType returns true just in case TargetType is in the type hierarchy that contains obj.
See Sun's tutorial
Answered by: Owen702 | Posted: 01-03-2022Similar questions
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