### Question:
PropertyUtil { public static String stripBefore(String value, char c) { String result = value; if (value != null) { int index = value.indexOf(c); if (index > 0) { result = value.substring(0, index); } } return result; }  static URI replaceQuery(URI originalURI, Map<String, String> properties); static URI replaceQuery(URI uri, String query); static URI eraseQuery(URI uri); static String createQueryString(Map<String, ? extends Object> options); static Map<String, String> parseQuery(URI uri); static Map<String, String> parseQuery(String queryString); static Map<String, String> filterProperties(Map<String, String> properties, String optionPrefix); static Map<String, String> setProperties(Object target, Map<String, String> properties); static Map<String, Object> setProperties(Object target, Properties properties); static Map<String, String> getProperties(Object object); static Object getProperty(Object object, String name); static boolean setProperty(Object target, String name, Object value); static String stripPrefix(String value, String prefix); static String stripUpto(String value, char c); static String stripBefore(String value, char c);  }### Answer:
@Test public void testStripBefore() { String value = "prefixed.option"; String result = PropertyUtil.stripBefore(value, '.'); assertEquals("prefixed", result); }
@Test public void testStripBeforeNullString() { assertNull(PropertyUtil.stripBefore((String) null, '.')); }