Re: Interface instanceof
what about t ?
Oliver Wong wrote:
"gk" <srcjnu@gmail.com> wrote in message
news:1158251720.896030.224920@p79g2000cwp.googlegroups.com...
interface MyInterface {
}
public class MyInstanceTest implements MyInterface {
static String s;
public static void main(String args[]) {
MyInstanceTest t = new MyInstanceTest();
if (t instanceof MyInterface) {
System.out.println("I am true interface");
} else {
System.out.println("I am false interface");
}
if (s instanceof String) {
System.out.println("I am true String");
} else {
System.out.println("I am false String");
}
}
}
output:
I am true interface
I am false String
this is quite confusing.
[...]
is this if block is false because of s is not created via new operator
?
It's false because s is null, and null is considered to not be an
instanceof anything (not even Object).
- Oliver
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