Strings { @Deprecated public static String nullToEmpty(String string) { return (string == null) ? "" : string; } private  Strings(); @Deprecated static String nullToEmpty(String string); @Deprecated static String emptyToNull(String string); @Deprecated static boolean isNullOrEmpty(String string); @Deprecated static String join(String delimiter, String... parts); @Deprecated static String[] split(String raw, char ch); @Deprecated static String longestCommonPrefix(String... input);  }
@Test public void testNullToEmpty() { assertEquals(Strings.nullToEmpty(null), ""); assertEquals(Strings.nullToEmpty(""), ""); assertEquals(Strings.nullToEmpty("a"), "a"); }