### Question:
CurrencyMappings { public static boolean isNamespaceAvailable(String namespace) { return CURRENCIES_SPI.isNamespaceAvailable(namespace); } private  CurrencyMappings(); static boolean isNamespaceAvailable(String namespace); static Set<String> getNamespaces(); static Set<String> getNamespaces(String currencyCode); static Set<String> getNamespaces(CurrencyUnit currencyUnit); static CurrencyQuery getNamespaceQuery(String namespace); static CurrencyQuery getMappingQuery(CurrencyUnit currencyUnit,
                                                String targetNamespace);  }### Answer:
@Test public void testIsNamespaceAvailable() { assertTrue(CurrencyMappings.isNamespaceAvailable("ISO-4217")); assertFalse(CurrencyMappings.isNamespaceAvailable("foo")); }