I am attempting to use PowerMock to mock some third party code and I am having an issue with an extended method.
So I will give a snippet showing what is occuring.
ClassA extends ClassB{
super();
}
ClassB extends ClassC{
super();
}
ClassC {
String methodA();
}
Now I am attempting to mock ClassA as that is what my code is using. The mock creates fine, however when I add an expectation like so:
expect(mockClassA.methodA()).andReturn("string");
I get the following error:
java.lang.IllegalStateException: missing behavior definition for the preceding method call methodA()
at org.easymock.internal.MockInvocationHandler.invoke(MockInvocationHandler.java:43)
at org.powermock.api.easymock.internal.invocationcontrol.EasyMockMethodInvocationControl.invoke(EasyMockMethodInvocationControl.java:95)
at org.powermock.core.MockGateway.doMethodCall(MockGateway.java:104)
at org.powermock.core.MockGateway.methodCall(MockGateway.java:167)
at .ClassC.methodA(ClassC.java)
Any thoughts on what I am missing? I know I haven't included much detail, but I have prepared ClassA for test using the notation, I have also only put the replay in one place to ensure that I am not incorrectly putting mockClassA into the wrong state before setting the expectation.
I did something like this and it works for me, however I dont understand why you need PowerMock here(you can do that without it with EasyMock/Mockito).
#RunWith(PowerMockRunner.class)
#PrepareForTest(ClassA.class)
public class ClassATest {
#Test
public void finalMethodString() throws Exception {
ClassA f = PowerMock.createNiceMock(ClassA.class);
EasyMock.expect(f.methodA()).andReturn("haha");
EasyMock.replay(f);
assertEquals("haha1", f.methodA());
}
}
class ClassA extends ClassB{
#Override
String methodA() {
return "1";
}
}
class ClassB extends ClassC{
#Override
String methodA() {
return "b";
}
}
class ClassC {
String methodA() {
return null;
}
}
Related
I am very new with Mockito and I don't get the following example (classes were provided, only test to write) and how to solve it.
What I try to do is use a test double for the supplier so that we can control the returned greeting in the test and assert that the GreetingService does not modify the greeting message in any way. Then assert that the returned greeting string is equal to "Hello Andy.".
public class Greeting {
private final String template;
public Greeting(String template) {
this.template = template;
}
public String forName(String world) {
return String.format(template, world);
}
}
#Component
public class GreetingService {
private final Supplier<Greeting> greetingSupplier;
public GreetingService(Supplier<Greeting> greetingSupplier) {
this.greetingSupplier = greetingSupplier;
}
public String greet(String name) {
return greetingSupplier.get().forName(name);
}
}
#Component
public class RandomGreetingSupplier implements Supplier<Greeting> {
private final List<Greeting> greetings = Arrays.asList(
new Greeting("Hello %s."),
new Greeting("Hi %s!"),
);
private final Random random = new Random();
#Override
public Greeting get() {
return greetings.get(random.nextInt(greetings.size()));
}
}
#SpringBootTest
public class GreetingServiceTest {
#Autowired
GreetingService greetingService;
#MockBean
Supplier<Greeting> greetingSupplier;
#Test
void getGreetingForPerson() {
String name = "Andy";
// that test cannot know which greeting will be returned by the supplier
// WHY IS IT NULLPOINTEREXCEPTION AFTER INITIALIZING #MockBean
//String greeting = greetingService.greet(name);
//assertThat(greeting).contains(name);
// WROTE SUCH TEST HERE -> NullPointerException WHY?
Mockito.when(greetingSupplier.get().forName(name)).thenReturn("Hello %s.");
assertThat(greetingSupplier.equals("Hello Andy."));
// THIS IS WORKING & TEST PASSED BUT I GUESS ITS WRONG?
Mockito.when(greetingSupplier.get()).thenReturn(new Greeting("Hello %s."));
assertThat(greetingSupplier.equals("Hello Andy."));
}
}
Mockito.when(greetingSupplier.get().forName(name)).thenReturn("Hello %s.");
You can't chain calls like that, you need to produce intermediate results, like
Supplier<Greeting> supplier = mock(Supplier.class);
Mockito.when(supplier).forName().thenReturn("Hello %s.");
Mockito.when(greetingSupplier.get()).thenReturn(supplier);
For dependency injection, you need to create the subject under test with the mocked Supplier. You can do that in a #Before method for example.
Your mocking is wrong.
Mockito.when(greetingSupplier.get().forName(name)).thenReturn("Hello %s.");
You mocked Supplier<Greeting> and the default behavior is to return null. So when you call greetingSupplier.get() in your first line it returns null. You directly chain forName which nou basicall is null.forName which leads to an error.
Your second part is actually (kind of) correct.
Mockito.when(greetingSupplier.get()).thenReturn(new Greeting("Hello %s."));
You now properly return a response from greetingSupplier.get(). Instead of chaining the call.
However I would argue that your excercise is wrong. Why? When using a Supplier<?> in Spring it actually is a lazy beanFactory.getBean call. You can lazily inject dependencies this way. You should have a mock for Greeting which returns a hardcoded String which you can check.
JUnit's #BeforeClass annotation must be declared static if you want it to run once before all the #Test methods. However, this cannot be used with dependency injection.
I want to clean up a database that I #Autowire with Spring Boot, once before I run my JUnit tests. I cannot #Autowire static fields so I need to think of a work around. Any ideas?
Just use #Before (instead of #BeforeClass) (or Spring's #BeforeTransaction (depending on how you initialize the database)). This annotation must been attached to an nonstatic public method.
Of course: #Before run before EACH test case method (not like #BeforeClass that runs only once.) But if you want to run it exactly once, then use an static marker field.
private static boolean initialized = false;
...
#Before
public void initializeDB() {
if (!initialized) {
... //your db initialization
initialized = true;
}
}
---
For JUnit5: Test Execution Order and #TestInstance(Lifecycle.PER_CLASS)
Kotlin example:
#ExtendWith(SpringExtension::class)
#TestInstance(PER_CLASS)
class BeforeInstanceTests {
private var initialized: String = ""
private val callList: MutableList<String> = ArrayList()
#BeforeAll
fun beforeAllNonStatic() {
initialized = "initialized"
assertEquals(0, callList.size)
}
#Test
fun test1() {
assertEquals("initialized", initialized)
callList.add("test1")
}
#Test
fun test2() {
assertEquals("initialized", initialized)
callList.add("test2")
}
#Test
fun test3() {
assertEquals("initialized", initialized)
callList.add("test3")
}
#AfterAll
fun afterAllNonStatic() {
assertEquals("initialized", initialized)
assertEquals(3, callList.size)
assertTrue(callList.contains("test1"))
assertTrue(callList.contains("test2"))
assertTrue(callList.contains("test3"))
callList.clear()
initialized = ""
}
}
Have a look at the DBUnit library - it's designed to perform the actions you're describing. It can create & tear down database instances and provides you with simple ways to do this.
Though accepted answer is clever, seems hacky. Have you tried using a normal Constructor?
public class MyJUnitTest {
public MyJUnitTest() {
// code for initializeDB
}
// Tests
}
Try this solution:
https://stackoverflow.com/a/46274919/907576 :
with #BeforeAllMethods/#AfterAllMethods annotations you could execute any method in Test class in an instance context, where all injected values are available.
I'm using Spring 3.1.4.RELEASE and Mockito 1.9.5. In my Spring class I have:
#Value("#{myProps['default.url']}")
private String defaultUrl;
#Value("#{myProps['default.password']}")
private String defaultrPassword;
// ...
From my JUnit test, which I currently have set up like so:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration({ "classpath:test-context.xml" })
public class MyTest
{
I would like to mock a value for my "defaultUrl" field. Note that I don't want to mock values for the other fields — I'd like to keep those as they are, only the "defaultUrl" field. Also note that I have no explicit "setter" methods (e.g. setDefaultUrl) in my class and I don't want to create any just for the purposes of testing.
Given this, how can I mock a value for that one field?
You can use the magic of Spring's ReflectionTestUtils.setField in order to avoid making any modifications whatsoever to your code.
The comment from Michał Stochmal provides an example:
use ReflectionTestUtils.setField(bean, "fieldName", "value"); before invoking your bean method during test.
Check out this tutorial for even more information, although you probably won't need it since the method is very easy to use
UPDATE
Since the introduction of Spring 4.2.RC1 it is now possible to set a static field without having to supply an instance of the class. See this part of the documentation and this commit.
It was now the third time I googled myself to this SO post as I always forget how to mock an #Value field. Though the accepted answer is correct, I always need some time to get the "setField" call right, so at least for myself I paste an example snippet here:
Production class:
#Value("#{myProps[‘some.default.url']}")
private String defaultUrl;
Test class:
import org.springframework.test.util.ReflectionTestUtils;
ReflectionTestUtils.setField(instanceUnderTest, "defaultUrl", "http://foo");
// Note: Don't use MyClassUnderTest.class, use the instance you are testing itself
// Note: Don't use the referenced string "#{myProps[‘some.default.url']}",
// but simply the FIELDs name ("defaultUrl")
You can use this magic Spring Test annotation :
#TestPropertySource(properties = { "my.spring.property=20" })
see
org.springframework.test.context.TestPropertySource
For example, this is the test class :
#ContextConfiguration(classes = { MyTestClass.Config.class })
#TestPropertySource(properties = { "my.spring.property=20" })
public class MyTestClass {
public static class Config {
#Bean
MyClass getMyClass() {
return new MyClass ();
}
}
#Resource
private MyClass myClass ;
#Test
public void myTest() {
...
And this is the class with the property :
#Component
public class MyClass {
#Value("${my.spring.property}")
private int mySpringProperty;
...
I'd like to suggest a related solution, which is to pass the #Value-annotated fields as parameters to the constructor, instead of using the ReflectionTestUtils class.
Instead of this:
public class Foo {
#Value("${foo}")
private String foo;
}
and
public class FooTest {
#InjectMocks
private Foo foo;
#Before
public void setUp() {
ReflectionTestUtils.setField(Foo.class, "foo", "foo");
}
#Test
public void testFoo() {
// stuff
}
}
Do this:
public class Foo {
private String foo;
public Foo(#Value("${foo}") String foo) {
this.foo = foo;
}
}
and
public class FooTest {
private Foo foo;
#Before
public void setUp() {
foo = new Foo("foo");
}
#Test
public void testFoo() {
// stuff
}
}
Benefits of this approach: 1) we can instantiate the Foo class without a dependency container (it's just a constructor), and 2) we're not coupling our test to our implementation details (reflection ties us to the field name using a string, which could cause a problem if we change the field name).
You can also mock your property configuration into your test class
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration({ "classpath:test-context.xml" })
public class MyTest
{
#Configuration
public static class MockConfig{
#Bean
public Properties myProps(){
Properties properties = new Properties();
properties.setProperty("default.url", "myUrl");
properties.setProperty("property.value2", "value2");
return properties;
}
}
#Value("#{myProps['default.url']}")
private String defaultUrl;
#Test
public void testValue(){
Assert.assertEquals("myUrl", defaultUrl);
}
}
I used the below code and it worked for me:
#InjectMocks
private ClassABC classABC;
#Before
public void setUp() {
ReflectionTestUtils.setField(classABC, "constantFromConfigFile", 3);
}
Reference: https://www.jeejava.com/mock-an-autowired-value-field-in-spring-with-junit-mockito/
Also note that I have no explicit "setter" methods (e.g. setDefaultUrl) in my class and I don't want to create any just for the purposes of testing.
One way to resolve this is change your class to use Constructor Injection, that can be used for testing and Spring injection. No more reflection :)
So, you can pass any String using the constructor:
class MySpringClass {
private final String defaultUrl;
private final String defaultrPassword;
public MySpringClass (
#Value("#{myProps['default.url']}") String defaultUrl,
#Value("#{myProps['default.password']}") String defaultrPassword) {
this.defaultUrl = defaultUrl;
this.defaultrPassword= defaultrPassword;
}
}
And in your test, just use it:
MySpringClass MySpringClass = new MySpringClass("anyUrl", "anyPassword");
Whenever possible, I set the field visibility as package-protected so it can be accessed from the test class. I document that using Guava's #VisibleForTesting annotation (in case the next guy wonders why it's not private). This way I don't have to rely on the string name of the field and everything stays type-safe.
I know it goes against standard encapsulation practices we were taught in school. But as soon as there is some agreement in the team to go this way, I found it the most pragmatic solution.
Another way is to use #SpringBootTest annotation properties field.
Here we override example.firstProperty property:
#SpringBootTest(properties = { "example.firstProperty=annotation" })
public class SpringBootPropertySourceResolverIntegrationTest {
#Autowired private PropertySourceResolver propertySourceResolver;
#Test
public void shouldSpringBootTestAnnotation_overridePropertyValues() {
String firstProperty = propertySourceResolver.getFirstProperty();
String secondProperty = propertySourceResolver.getSecondProperty();
Assert.assertEquals("annotation", firstProperty);
Assert.assertEquals("defaultSecond", secondProperty);
}
}
As you can see It overrides only one property. Properties not mentioned in #SpringBootTest stay untouched. Therefore, this is a great solution when we need to override only specific properties for the test.
For single property you can write it without braces:
#SpringBootTest(properties = "example.firstProperty=annotation")
Answer from: https://www.baeldung.com/spring-tests-override-properties#springBootTest
I also encourage you to whenever possible pass property as a parameter in constructor like in Dherik answer (https://stackoverflow.com/a/52955459/1673775) as it enables you to mock properties easily in unit tests.
However in integration tests you often don't create objects manually, but:
you use #Autowired
you want to modify property used in a class that is used in your integration test indirectly as it is deep dependency of some directly used class.
then this solution with #SpringBootTest might be helpful.
I would like to use both #Post and #Get on the same method like
#GET
#POST
#Path("{mode}")
public void paymentFinish(#PathParam("mode") String mode, String s) {
logger.debug("Enter PayStatus POST");
logger.debug(mode);
}
Even I write like this, I got error. What I want is whatever get or post to the sameurl, the same method works. Is it possible? Now I separate two methods, one for get and one for post.
Unfortunately, only one should be used in order to avoid Jersey exception.
But you could do something like :
#GET
#Path("{mode}")
public void paymentFinish(#PathParam("mode") String mode, String s) {
commonFunction(mode);
}
#POST
#Path("{mode}")
public void paymentFinishPOST(#PathParam("mode") String mode, String s) {
commonFunction(mode);
}
private void commonFunction(String mode)
{
logger.debug("Enter PayStatus POST");
logger.debug(mode);
}
By doing so, if you want to change inner behavior of your functions, you will only have to change one function.
Note that method name in java for get vs post need to be different.
After searching a lot trying to avoid the solution above, I found nothing....
Then I decided to create a custom annotation so I didn't have to waste time duplicating methods.
Here's the github link: Jersey-Gest
It allows you to create GET and Post Methods on a single Annotation by generating a new class from it.
I hope it helps you the same way it helped me :)
Edit:
If for some reason the above link stops working, here's what I did:
Created a compile-time annotation #RestMethod for class methods.
Created a compile-time annotation #RestClass for classes.
Create an AnnotationProcessor which generates a new class with Jersey's corresponding annotations and for each method creates a GET and a POST method which callsback to the original method annotated with #RestClass.
All methods annotated with #RestMethod must be static and contained within a class annotated with #RestClass.
Example (TestService.java):
#RestClass(path = "/wsdl")
public class TestService
{
#RestMethod(path = "/helloGest")
public static String helloGest()
{
return "Hello Gest!";
}
}
Generates something like (TestServiceImpl.java):
#Path("/wsdl")
#Produces("application/xml")
public class TestServiceImpl
{
#GET
#Path("/helloGest")
#Produces(MediaType.APPLICATION_XML)
public String helloGestGet()
{
return TestService.helloGest();
}
#POST
#Path("/helloGest")
#Consumes(MediaType.WILDCARD)
#Produces(MediaType.APPLICATION_XML)
public String helloGestPost()
{
return TestService.helloGest();
}
}
If I declare a method :
public Car makeCar(#Named("carClassName") String carClassName){
//...
}
It seems that the compiler (eclipse) is unhappy (i.e. it won't let me call the class with no arguments).
How can I inject these parameters when I call this method , dynamically ? Is there a way to inject a call to a method ?
Solution 1: insert carClassName in the caller,
class Whatever {
private #Named("carClassName") String carClassName);
public void dosomething() {
...
Cat cat = makeCar(carclassName);
...
}
}
Solution 2: use a factory,
class CarFactory {
private #Named("carClassName") String carClassName);
public Car create() {
return makeCar(carClassName);
}
}
and inject it where needed.