@Test
    public void testFreeze() {
        ListMap<String, String> map = initSimpleMap();
        map.freeze();
        try {
            map.put("key", "value");
            fail("Expected exception");
        }
        catch (Exception expected) {
        }
        try {
            map.entrySet().iterator().next().getValue().add("foo");
            fail("Expected exception");
        }
        catch (Exception expected) {
        }
    }
@author <a href="mailto:einarmr@yahoo-inc.com">Einar M R Rosenvinge</a>
vespajlib/src/test/java/com/yahoo/collections/ListMapTestCase.java