### Question:
MethodCoercions { public static Maybe<?> tryFindAndInvokeSingleParameterMethod(final Object instance, final String methodName, final Object argument) { Class<?> clazz = instance.getClass(); Iterable<Method> methods = Arrays.asList(clazz.getMethods()); Optional<Method> matchingMethod = Iterables.tryFind(methods, matchSingleParameterMethod(methodName, argument)); if (matchingMethod.isPresent()) { Method method = matchingMethod.get(); try { Type paramType = method.getGenericParameterTypes()[0]; Object coercedArgument = TypeCoercions.coerce(argument, TypeToken.of(paramType)); return Maybe.of(method.invoke(instance, coercedArgument)); } catch (IllegalAccessException | InvocationTargetException e) { throw Exceptions.propagate(e); } } else { return Maybe.absent(); } }  static Predicate<Method> matchSingleParameterMethod(final String methodName, final Object argument); static Maybe<?> tryFindAndInvokeSingleParameterMethod(final Object instance, final String methodName, final Object argument); static Predicate<Method> matchMultiParameterMethod(final String methodName, final List<?> arguments); static Maybe<?> tryFindAndInvokeMultiParameterMethod(final Object instance, final String methodName, final List<?> arguments); static Maybe<?> tryFindAndInvokeBestMatchingMethod(final Object instance, final String methodName, final Object argument);  }### Answer:
@Test public void testTryFindAndInvokeSingleParameterMethod() throws Exception { TestClass instance = new TestClass(); Maybe<?> maybe = MethodCoercions.tryFindAndInvokeSingleParameterMethod(instance, "singleParameterMethod", "42"); assertTrue(maybe.isPresent()); assertTrue(instance.wasSingleParameterMethodCalled()); }