How to verify method call typsafe in junit with spring? - java

how can I replace the methodName("getEmployeeDetailsById") with a typesafe expression? Somehow linking directly to the method of the class. Is that possible?
#RunWith(SpringRunner.class)
#WebMvcTest
public class MyTest {
#Test
public void test() {
mockMvc
.perform(get("/employee/details/9816"))
.andExpect(handler().handlerType(EmployeeController.class))
.andExpect(handler().methodName("getEmployeeDetailsById")); //TODO typesafe?
}

If I don't misunderstand your intention, you want build the expectation in static way.
You can use spring HandlerResultMatchers#methodCall & MvcUriComponentsBuilder#on to achieve your way, for example:
mockMvc.perform(get("/employee/details/9816")).andExpect(
handler().methodCall(on(EmployeeController.class).getEmployeeDetailsById(args))
// args is any of the arbitrary value just to make the code to compile ---^
)
But one thing you need to note is that MvcUriComponentsBuilder#on will create a proxy to be able to inspect the previous invocations. when you make the handler method to return a String view name, you should make the return type of handler method with its super type (super interface or superclass) of the String class, since it is final and can't be proxied by cglib. for example:
#RequestMapping("/foo")
public Object handlerReturnViewName() {
// ^--- use the super type instead
return "bar";
}

You can find the method in your Controller which has a #GetMapping annotation (i'm assuming what annotation you use here, adjust as required) with the value of "/employee/details/{id}" by searching for it over all methods in the class:
private String findMethodName() {
List<Method> methods =
new ArrayList<>(Arrays.asList(EmployeeController.class.getMethods());
for (Method method : methods) {
if (method.isAnnotationPresent(GetMapping.class)) {
GetMapping annotation = method.getAnnotation(GetMapping.class);
if(Arrays.asList(annotation.value())
.contains("/employee/details/{id}") {
return method.getName();
}
}
}
}
Then you can call this method in your mvcTest:
.andExpect(handler().methodName(findMethodName()));

Related

How do I get class annotations from a Method instance?

Consider the following class:
#ClassAnnotation1
#ClassAnnotation2
class MyClass {
// ...
#MethodAnnotation1
#MethodAnnotation2
private void myMethod(#ParamAnnotation1 #ParamAnnotation2 int i) {
// ...
}
}
During a reflection phase of my application, I need to analyze various code aspects, given a Method instance.
public void analyze(final Method method) {
// do the analysis...
// for example here, method is an instance of myMethod in MyClass
}
I can easily analyze the parameters' Annotation by doing
for (Parameter p : method.getParameters()) {
if (p.getAnnotation(ParamAnnotation1.class) != null) {
// ...
}
}
and get the results I expect.
The method's Annotation's can easily be processed with
method.getAnnotation(MethodAnnotation1.class)
Unfortunately I fail to get the expected results for the class' Annotation's.
In fact, the call to
method.getClass().getAnnotation(ClassAnnotation1.class)`
returns null, whereas MyClass is clearly annotated by #ClassAnnotation1.
How do I get the MyClass annotations from a Method instance?
You have to use method.getDeclaringClass().getAnnotation(ClassAnnotation1.class)
The fact that method.getParameters() returns the method's parameters, probably mislead you into thinking that method.getClass() returns the class containing your method.
Method::getClass() in fact returns Class<? extends Method>, which is clearly not annotated by #ClassAnnotation1. That's why you got null

how to read runtime annotations on a field within a class

Imagine an annotation called "MyAnn" with runtime retention, a class MyClass, and an abstract class called MyData. MyClass has a field of type MyData, annotated with MyAnn. Within the instance of MyData, how do see if the annotation MyAnn is present and retrieve its information?
Note - in Java8 I know we can directly annotate the inner class at construction - and that works - but I need this working based on the field annotation.
Thanks for any help!
public MyClass extends MySuperClass() {
#MyAnn(value = "something")
protected MyData mydata;
public void doSomething() {
mydata = new MyData() {};
mydata.initialize();
}
}
public abstract MyData() {
String myValue = null;
public void initialize() {
if (***I am annotated with MyAnn) {
myValue = (***value from annotation MyAnn);
}
}
}
#Retention(RetentionPolicy.RUNTIME)
public #interface MyAnn {
String myvalue;
}
MyData cannot directly know whether it has been annotated with MyAnn, because it has no knowledge of whether the current instance is a field or a standalone instance, and if it is a field, then whether the field has or has not been annotated with MyAnn.
So, you will need to somehow obtain and pass the value to initialize(), and you will need to somehow obtain the value at the place where initialize() is called. And from your code, it appears that "something" can be passed as a parameter to initialize(), making the whole thing a lot easier than annotating the field and then checking whether the field is annotated.
But in any case, if you want to check whether a field is annotated, you have to:
obtain the fields of your class with getClass().getDeclaredFields()
loop over the fields; for each field, either
invoke isAnnotationPresent( MyAnn.class ) or
invoke field.getAnnotations(), loop for each annotation, and check whether this annotation instanceof MyAnn.class
Once you have found the annotation, you can get its value with annotation.value();

Verify that all getter methods are called

I have the following test where I need to verify that all getters of the Person class are being called. So far I have used mockito's verify() to make sure that each getter is called. Is there a way to do that by reflection? It can be the case that a new getter is added to the Person class but the test will miss that.
public class GetterTest {
class Person{
private String firstname;
private String lastname;
public String getFirstname() {
return firstname;
}
public String getLastname() {
return lastname;
}
}
#Test
public void testAllGettersCalled() throws IntrospectionException{
Person personMock = mock(Person.class);
personMock.getFirstname();
personMock.getLastname();
for(PropertyDescriptor property : Introspector.getBeanInfo(Person.class).getPropertyDescriptors()) {
verify(personMock, atLeast(1)).getFirstname();
//**How to verify against any getter method and not just getFirstName()???**
}
}
}
Generally, don't mock the class under test. If your test is for a Person, you shouldn't ever see Mockito.mock(Person.class) in it, as that's a pretty clear sign that you're testing the mocking framework instead of the system-under-test.
Instead, you may want to create a spy(new Person()), which will create a real Person implementation using a real constructor and then copy its data to a Mockito-generated proxy. You can use MockingDetails.getInvocations() to reflectively check that every getter was called.
// This code is untested, but should get the point across. Edits welcome.
// 2016-01-20: Integrated feedback from Georgios Stathis. Thanks Georgios!
#Test
public void callAllGetters() throws Exception {
Person personSpy = spy(new Person());
personSpy.getFirstname();
personSpy.getLastname();
assertAllGettersCalled(personSpy, Person.class);
}
private static void assertAllGettersCalled(Object spy, Class<?> clazz) {
BeanInfo beanInfo = Introspector.getBeanInfo(clazz);
Set<Method> setOfDescriptors = beanInfo.getPropertyDescriptors()
.stream()
.map(PropertyDescriptor::getReadMethod)
.filter(p -> !p.getName().contains("getClass"))
.collect(Collectors.toSet());
MockingDetails details = Mockito.mockingDetails(spy);
Set<Method> setOfTestedMethods = details.getInvocations()
.stream()
.map(InvocationOnMock::getMethod)
.collect(Collectors.toSet());
setOfDescriptors.removeAll(setOfTestedMethods);
// The only remaining descriptors are untested.
assertThat(setOfDescriptors).isEmpty();
}
There might be a way to call verify and invoke on the Mockito-generated spy, but that seems very fragile, and very dependent on Mockito internals.
As an aside, testing bean-style getters seems like an odd use of time/effort. In general focus on testing implementations that are likely to change or break.
I can think of two solutions for your problem:
Generate the Builder code programmatically, so you don't need to run tests. Java code is generated by a program and never edited by a user. Test the generator instead. Use a text template and build definitions from a serialized domain model or directly from Java compiled classes (you'll need a separate module dependent on the bean's one)
Write your tests against a proxy library. The problem is that regular proxies can only implement interfaces, not regular classes, and it's very cumbersome to have interfaces for Javabeans. If you choose this route, I'd go with Javassist. I coded a runnable sample and put it on GitHub. The test cases use a proxy factory to instantiate beans (instead of using new)
public class CountingCallsProxyFactory {
public <T> T proxy(Class<T> classToProxy) {
ProxyFactory factory = new ProxyFactory();
factory.setSuperclass(classToProxy);
Class clazz = factory.createClass();
T instance = (T) clazz.newInstance();
ProxyObject proxy = (ProxyObject) instance;
MethodCallCounter handler = new MethodCallCounter();
proxy.setHandler(handler);
return instance;
}
public void verifyAllGettersCalled(Object bean) {
// Query the counter against the properties in the bean
}
}
The counter is kept inside the class MethodCallCounter

Java CDI: Dynamically selecting an implementation based on qualifier?

I'm trying to make an application extensible by using CDI, but it seems like I'm missing a piece of the puzzle.
What I want:
Have a global configuration that will define which implementation of an interface to use. The implementations would have annotations like #ImplDescriptor(type="type1").
What I tried:
#Produces
public UEInterface createUserExit(#Any Instance<UEInterface> instance, InjectionPoint ip) {
Annotated annotated = ip.getAnnotated();
UESelect ueSelect = annotated.getAnnotation(UESelect.class);
if (ueSelect != null) {
System.out.println("type = " + ueSelect.type());
}
System.out.println("Inject is ambiguous? " + instance.isAmbiguous());
if (instance.isUnsatisfied()) {
System.out.println("Inject is unsatified!");
return null;
}
// this would be ok, but causes an exception
return instance.select(ueSelect).get();
// or rather this:
for (Iterator<UEInterface> it = instance.iterator(); it.hasNext();) {
// problem: calling next() will trigger instantiation which will call this method again :(
UEInterface candidate = it.next();
System.out.println(candidate.getClass().getName());
}
}
This code is close to an example I've seen: The #Produces method will be used to select and create instances and a list of candidates is injected as Instance<E>. If the method simply creates and returns an implementation, it works fine. I just don't know how to examine and select a candidate from the Instance<E>. The only way of looking the the "contents" seems to be an Iterator<E>. But as soon as I call next(), it will try to create the implementation... and unfortunately, calls my #Produces method for that, thereby creating an infinite recursion. What am I missing? How can I inspect the candidates and select one? Of course I want to instantiate only one of them...
Thanks in advance for any help and hints!
I think the issue is you are trying to select the annotation's class rather than using the annotation as a selector qualifier. Using the class directly searches for an implementation that implements that class. You need to create an AnnotationLiteral using the #ImplDescriptor class to perform a select using it as a qualifier. Create a class extending AnnotationLiteral like so.
public class ImplDescriptorLiteral extends AnnotationLiteral<ImplDescriptor> implements ImplDescriptor {
private String type;
public ImplDescriptorLiteral(String type) {
this.type = type;
}
#Override
public String type() {
return type;
}
}
then you can pass an instance of this class to the select method using the type you want.
instance.select(new ImplDescriptorLiteral("type1")).get();
Refer to the Obtaining a contextual instance by programmatic lookup documentation for more information.
Finch, what you have here should work. it assumes though that you have an instance of UEInterface that is annotated #UESelect, e.g.
#UESelect("one")
public class UEOne implements UEInterface {
..
}
Is this how you're expecting it to work?

How to inject String constants easily with Weld?

We have a situation where we provide an external configuration in form of a Map to our running programs. I have found that JSR-330 Dependency Injection gives a much cleaner way to use that configuration map in the code instead of passing the map around or to use JNDI to get it.
#Inject #Named("server.username") String username;
lets the JSR-330 implementation fill in this field automatically.
With Guice I can set the value with
bindConstant().annotatedWith(Names.named(key)).to(value);
I would like to be able to do the same in Weld (bind "server.username" to e.g. "foobar") and I understand that the mechanism most likely is beans.xml, but I would prefer a simple "feed this map to Weld, please" code alternative. What would be a good way to do this?
EDIT 2013-10-16: After looking into Dagger which works at compile time and not runtime, I found that with us usually having 10-20 per program we could live with having a #Provider method for each configuration string which then looks up in the configuration map. This allows for method specific behavior (including default values), ability to provide javadoc, and ability to put all these methods in the same class. Also it works well with Weld out of the box. I am considering writing a fuller explanation in a blog entry.
I'd like that bounty now please. Figuring this out taught me quite a bit about the innards of WELD, and here's the most interesting lesson: #Named is a qualifier, and must be treated as such if you are going to be able to match against it.
I do have a warning for you: If you are missing any values in your app, it will fail at deploy or load time. This may be desirable for you, but it does specifically mean that "default" values are not possible.
The injection point is specified exactly as you have above, and here's the extension code needed to make it work:
#ApplicationScoped
public class PerformSetup implements Extension {
Map<String, String> configMap;
public PerformSetup() {
configMap = new HashMap<String, String>();
// This is a dummy initialization, do something constructive here
configMap.put("string.value", "This is a test value");
}
// Add the ConfigMap values to the global bean scope
void afterBeanDiscovery(#Observes AfterBeanDiscovery abd, BeanManager bm) {
// Loop through each entry registering the strings.
for (Entry<String, String> configEntry : configMap.entrySet()) {
final String configKey = configEntry.getKey();
final String configValue = configEntry.getValue();
AnnotatedType<String> at = bm.createAnnotatedType(String.class);
final InjectionTarget<String> it = bm.createInjectionTarget(at);
/**
* All of this is necessary so WELD knows where to find the string,
* what it's named, and what scope (singleton) it is.
*/
Bean<String> si = new Bean<String>() {
public Set<Type> getTypes() {
Set<Type> types = new HashSet<Type>();
types.add(String.class);
types.add(Object.class);
return types;
}
public Set<Annotation> getQualifiers() {
Set<Annotation> qualifiers = new HashSet<Annotation>();
qualifiers.add(new NamedAnnotationImpl(configKey));
return qualifiers;
}
public Class<? extends Annotation> getScope() {
return Singleton.class;
}
public String getName() {
return configKey;
}
public Set<Class<? extends Annotation>> getStereotypes() {
return Collections.EMPTY_SET;
}
public Class<?> getBeanClass() {
return String.class;
}
public boolean isAlternative() {
return false;
}
public boolean isNullable() {
return false;
}
public Set<InjectionPoint> getInjectionPoints() {
return it.getInjectionPoints();
}
#Override
public String create(CreationalContext<String> ctx) {
return configValue;
}
#Override
public void destroy(String instance,
CreationalContext<String> ctx) {
// Strings can't be destroyed, so don't do anything
}
};
abd.addBean(si);
}
}
/**
* This is just so we can create a #Named annotation at runtime.
*/
class NamedAnnotationImpl extends AnnotationLiteral<Named> implements Named {
final String nameValue;
NamedAnnotationImpl(String nameValue) {
this.nameValue = nameValue;
}
public String value() {
return nameValue;
}
}
}
I tested that this worked by making a WELD-SE app:
#ApplicationScoped
public class App {
#Inject
#Parameters
List<String> parameters;
#Inject
#Named("string.value")
String stringValue;
public void printHello(#Observes ContainerInitialized event) {
System.out.println("String Value is " + stringValue);
}
}
Lastly, don't forget /META-INF/services/javax.enterprise.inject.spi.Extension, replacing weldtest with the classpath you use:
weldtest.PerformSetup
That should make all of this work. Let me know if you run into any difficulties and I'll send you my test project.
Not all that interested in the bounty, but I'll take it if it's still on the table. This is VERY similar to some code I'm using at $DAYJOB, and so this isn't theory, it's what I use in production code, but modified to protect the guilty. I haven't tried compiling the modified code, so be warned that I may have made some errors in changing names and such, but the principles involved here have all been tested and work.
First, you need a Value Holder Qualifier. Use #Nonbinding to keep WELD from matching ONLY to qualifiers with identical values, since we want all values of this particular qualifier to match a single injection point. By keeping the qualifier and value in the same annotation, you can't just "forget" one of them by accident. (KISS principle)
#Qualifier
#Retention(RUNTIME)
#Target({METHOD, FIELD, PARAMETER, TYPE})
public #interface ConfigValue {
// Excludes this value from being considered for injection point matching
#Nonbinding
// Avoid specifying a default value, since it can encourage programmer error.
// We WANT a value every time.
String value();
}
Next, you need a producer method which knows how to get the Map. You should probably have a Named bean which holds the producer method, so you can either explicitly initialize the value by using getters/setters, or else have the bean initialize it for you.
We must specify a blank value for the qualifier on the producer method to avoid compile time errors, but it's never used in practice.
#Named
public class ConfigProducer {
//#Inject // Initialize this parameter somehow
Map<String,String> configurationMap;
#PostConstructor
public void doInit() {
// TODO: Get the configuration map here if it needs explicit initialization
}
// In general, I would discourage using this method, since it can be difficult to control exactly the order in which beans initialize at runtime.
public void setConfigurationMap(Map<String,String> configurationMap) {
this.configurationMap = configurationMap;
}
#Produces
#ConfigValue("")
#Dependent
public String configValueProducer(InjectionPoint ip) {
// We know this annotation WILL be present as WELD won't call us otherwise, so no null checking is required.
ConfigValue configValue = ip.getAnnotated().getAnnotation(ConfigValue.class);
// This could potentially return a null, so the function is annotated #Dependent to avoid a WELD error.
return configurationMap.get(configValue.value());
}
}
Usage is simple:
#Inject
#ConfigValue("some.map.key.here")
String someConfigValue;
It may be possible to implement this as an #Dependent Producer method that itself injects an #InjectionPoint which would allow you to reflect upon the field you're being injected into -- this would let you peek into a custom annotation (not a qualifier) member on the field to figure out the val you want to return
#Inject #ConfigMapQualifier #Val("user.name") String user;
...
#Produces #ConfigMapQualifier configProducr(...) {
...
#Inject InjectionPoint ip;
// use e.g. ip/getJavaMember() then reflection to figure out the #Val value membr.
Would implementing a custom Weld InjectionServices not be an option here ?
what about
#Resource(name = "server.username", type = java.lang.String.class)
private String injectTo;
Javadoc: http://download.oracle.com/javase/6/docs/api/javax/annotation/Resource.html

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