### Question:
CommonUtils { public static boolean isNotEmpty(Collection collection) { return collection != null && !collection.isEmpty(); }  static boolean isNotEmpty(Collection collection);  }### Answer:
@Test public void isNotEmpty() { Assert.assertTrue(CommonUtils.isNotEmpty(Collections.singletonList("xxx"))); Assert.assertFalse(CommonUtils.isNotEmpty(null)); Assert.assertFalse(CommonUtils.isNotEmpty(Collections.emptyList())); }