The awesome power of nullify

TestNullify.java

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import static org.junit.Assert.*;

@RunWith(JUnit4.class)
public class TestNullify {

	@Test
	public void objectFailsToNullify() {
		String x = "hello world";
		assertEquals("hello world", x);
		nullify(x);
		assertEquals("hello world", x);	
	}
	
        /**
         * This method only nulls the reference that has been copied by value - as it exits
         * obj will only be null in the scope of this method.  The object that it references
         * will retain its value.
	public static void nullify(Object obj) {
        if (obj != null) {
            obj = null;
        }
        assertNull(obj);
    }
}