In Eclipse, this code produces a warning at "foo.nextElement()" saying

"Type safety: The method nextElement() belongs to the raw type
Enumeration. References to generic type Enumeration<E> should be
parameterized"

    void listDefaults() {
        UIDefaults uiDefaults = UIManager.getDefaults();
        Enumeration foo = uiDefaults.keys();
        while (foo.hasMoreElements()) {
            Object key = foo.nextElement();
            Object val = uiDefaults.get(key);
            System.out.println("[" + key.toString() + "]:["
                    + (null != val ? val.toString() : "(null)") + "]");
        }
    }

How should I fix this?