GetPrimitive.java

public static void main(String[] args) {
    Stream.of(Boolean.class, Byte.class, Character.class, Short.class, Integer.class,
            Long.class, Float.class, Double.class, Void.class).map(c -> {
        try {
            return c.getField("TYPE").get(null);
        } catch (Exception e) {
            throw new AssertionError(e);
        }
    }).forEach(System.out::println);
}