### Question:
ExpressionLanguagePropertyConverter { public static String dmnFromWB(final ExpressionLanguage language) { if (language == null) { return null; } else if (StringUtils.isEmpty(language.getValue())) { return null; } else { return language.getValue(); } }  static ExpressionLanguage wbFromDMN(final String language); static String dmnFromWB(final ExpressionLanguage language);  }### Answer:
@Test public void testDMNFromWBWithNull() { assertNull(ExpressionLanguagePropertyConverter.dmnFromWB(null)); }
@Test public void testDMNFromWBWithNullValue() { assertNull(ExpressionLanguagePropertyConverter.dmnFromWB(new ExpressionLanguage(null))); }
@Test public void testDMNFromWBWithEmptyValue() { assertNull(ExpressionLanguagePropertyConverter.dmnFromWB(new ExpressionLanguage())); }
@Test public void testDMNFromWBWithNonNullValue() { assertEquals(EXPRESSION_LANGUAGE, ExpressionLanguagePropertyConverter.dmnFromWB(new ExpressionLanguage(EXPRESSION_LANGUAGE))); }