### Question:
I18nClientMessages { static String prepareForReactClient(String str) { return MessageFormat.format(str, (Object[])params); } private  I18nClientMessages(); static I18nClientMessages getInstance(); Map<String, String> getAllMessages(Locale locale, boolean keysOnly);  }### Answer:
@Test void prepareForClientTest() throws Exception { assertEquals("", I18nClientMessages.prepareForReactClient("")); assertEquals("Test", I18nClientMessages.prepareForReactClient("Test")); assertEquals("{0}", I18nClientMessages.prepareForReactClient("{0}")); assertEquals("{0}", I18nClientMessages.prepareForReactClient("'{0}'")); assertEquals("'{0}'", I18nClientMessages.prepareForReactClient("''{0}''")); assertEquals("{test}", I18nClientMessages.prepareForReactClient("'{test}'")); assertEquals("In sheet '{0}', column {1}:'{2}' and row #{3}: {{4}}", I18nClientMessages.prepareForReactClient("In sheet ''{0}'', column {1}:''{2}'' and row #{3}: '{'{4}'}'")); }