Why Java (server VM) is faster than D?

[aki via Digitalmars-d]

When I was trying to port some Java program to D,
I noticed Java is faster than D.
I made a simple bench mark test as follows.
Then, I was shocked with the result.

test results on Win8 64bit (smaller is better)
Java(1.8.0,64bit,server): 0.677
C++(MS vs2013): 2.141
C#(MS vs2013): 2.220
D(DMD 2.067.1): 2.448
D(GDC 4.9.2/2.066): 2.481
Java(1.8.0,32bit,client): 3.060

Does anyone know the magic of Java?

Thanks, Aki.

---

test program for D lang:
import std.datetime;
import std.stdio;
class Foo {
        int i = 0;
        void bar() {}
};
class SubFoo : Foo {
        override void bar() {
                i = i * 3 + 1;
        }
};
int test(Foo obj, int repeat) {
        for (int r = 0; r<repeat; ++r) {
                obj.bar();
        }
        return obj.i;
}
void main() {
        auto stime = Clock.currTime();
        int repeat = 1000 * 1000 * 1000;
        int ret = test(new SubFoo(), repeat);
        double time = (Clock.currTime() - stime).total!"msecs" / 1000.0;
        writefln("time=%5.3f, ret=%d", time, ret);
}

test program for Java:
class Foo {
        public int i = 0;
        public void bar() {}
};
class SubFoo extends Foo {
        public void bar() {
                i = i * 3 + 1;
        }
};
public class Main {
        public static int test(Foo obj, int repeat) {
                for (int r = 0; r<repeat; ++r) {
                        obj.bar();
                }
                return obj.i;
        }
        public static void main(String[] args) {
                long stime = System.currentTimeMillis();
                int repeat = 1000 * 1000 * 1000;
                int ret = test(new SubFoo(), repeat);
                double time = (System.currentTimeMillis() - stime) / 1000.0;
                System.out.printf("time=%5.3f, ret=%d", time, ret);
        }
}