### Question:
MethodsMapper extends FunctionMapper { @Override public Method resolveFunction(String prefix, String localName) { if (prefix != null && prefix.isEmpty() && localName != null) { return methods.get(localName); } return null; } @VisibleForTesting  MethodsMapper(final Map<String, Method> methods); @Override Method resolveFunction(String prefix, String localName); static final MethodsMapper INSTANCE; }### Answer:
@Test(dataProvider = "resolveFunctionUnsupportedParameters") public void shouldResolveFunctionReturnNull(final String prefix, final String methodName) { assertThat(new MethodsMapper(methods).resolveFunction(prefix, methodName)).isNull(); }
@Test public void shouldResolveFunctionWithEmptyPrefix() { MethodsMapper mp = new MethodsMapper(methods); assertThat(mp.resolveFunction("", "asLong")).isEqualTo(methods.get("asLong")); assertThat(mp.resolveFunction("", "urlEncodeFragment")).isEqualTo(null); mp = MethodsMapper.INSTANCE; assertThat(mp.resolveFunction("", "asLong")).isNull(); assertThat(mp.resolveFunction("", "urlEncodeFragment")).isNotNull(); }