Passing a class to a method?

Question

This doesn't work:
public Decorator findDecorator(String className) {
    if (this instanceof className)
        return this;
    else
        return null;
}My friend told me that in C# he just does this:
findDecorator(Type className)So how do I do it in Java?
Edited by: hidarikani on Apr 2, 2009 11:35 AM

Answer 1

You can use isAssignableFrom, but I've never needed to do this. Makes me wonder just what you are doing.
Demo:
public class Test {
    public static boolean hasType(Object x, Class<?> cls) {
        if (x == null) {
            return false;
        } else {
            return cls.isAssignableFrom(x.getClass());
    static void test(Object x, Class<?> cls) {
        System.out.format("new %s() hasType %s = %b%n",
            x.getClass().getName(), cls.getName(), hasType(x, cls));
    public static void main(String[] args) {
        //trues
        test(new A(), A.class);
        test(new AA(), AA.class);
        test(new AAA(), AAA.class);
        test(new AA(), A.class);
        test(new AAA(), AA.class);
        test(new AAA(), A.class);
        System.out.println();
        //falses
        test(new B(), A.class);
        test(new A(), AA.class);
        test(new A(), AAA.class);
        test(new AA(), AAA.class);
class A {}
class AA extends A {}
class AAA extends AA {}
class B {}