### Question:
NonEmptyValidator implements Validator { @Override public boolean isValid(String value) { return (value != null && !value.trim().isEmpty()); }  @Override boolean isValid(String value);  }### Answer:
@Test public void testGoodData() { assertTrue(validator.isValid("d")); assertTrue(validator.isValid("12350918509185")); }
@Test public void testBadData() { assertTrue(!validator.isValid("")); assertTrue(!validator.isValid(null)); assertTrue(!validator.isValid(" ")); assertTrue(!validator.isValid("\n")); assertTrue(!validator.isValid("\t\t\t")); assertTrue(!validator.isValid("\u0000")); }