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/*
 * Copyright (c) 2007 Mockito contributors
 * This program is made available under the terms of the MIT License.
 */
package org.mockito;

import org.mockito.internal.MockitoCore;
import org.mockito.internal.creation.MockSettingsImpl;
import org.mockito.internal.debugging.MockitoDebuggerImpl;
import org.mockito.internal.stubbing.answers.*;
import org.mockito.internal.stubbing.defaultanswers.ReturnsEmptyValues;
import org.mockito.internal.stubbing.defaultanswers.ReturnsMoreEmptyValues;
import org.mockito.internal.verification.VerificationModeFactory;
import org.mockito.junit.MockitoJUnitRule;
import org.mockito.runners.MockitoJUnitRunner;
import org.mockito.stubbing.*;
import org.mockito.verification.*;

/**
 * 

* Mockito library enables mocks creation, verification and stubbing. *

* This javadoc content is also available on the http://mockito.org web page. * All documentation is kept in javadocs because it guarantees consistency between what's on the web and what's in the source code. * Also, it makes possible to access documentation straight from the IDE even if you work offline. * *

Contents

* * * 1. Let's verify some behaviour!
* 2. How about some stubbing?
* 3. Argument matchers
* 4. Verifying exact number of invocations / at least once / never
* 5. Stubbing void methods with exceptions
* 6. Verification in order
* 7. Making sure interaction(s) never happened on mock
* 8. Finding redundant invocations
* 9. Shorthand for mocks creation - @Mock annotation
* 10. Stubbing consecutive calls (iterator-style stubbing)
* 11. Stubbing with callbacks
* 12. doReturn()|doThrow()|doAnswer()|doNothing()|doCallRealMethod() family of methods
* 13. Spying on real objects
* 14. Changing default return values of unstubbed invocations (Since 1.7)
* 15. Capturing arguments for further assertions (Since 1.8.0)
* 16. Real partial mocks (Since 1.8.0)
* 17. Resetting mocks (Since 1.8.0)
* 18. Troubleshooting & validating framework usage (Since 1.8.0)
* 19. Aliases for behavior driven development (Since 1.8.0)
* 20. Serializable mocks (Since 1.8.1)
* 21. New annotations: @Captor, @Spy, @InjectMocks (Since 1.8.3)
* 22. Verification with timeout (Since 1.8.5)
* 23. Automatic instantiation of @Spies, @InjectMocks and constructor injection goodness (Since 1.9.0)
* 24. One-liner stubs (Since 1.9.0)
* 25. Verification ignoring stubs (Since 1.9.0)
* 26. Mocking details (Since 1.9.5)
* 27. Delegate calls to real instance (Since 1.9.5)
* 28. MockMaker API (Since 1.9.5)
* 29. (new) BDD style verification (Since 1.10.0)
* 30. (new) Spying or mocking abstract classes (Since 1.10.12)
*
* *

* Following examples mock a List, because everyone knows its interface (methods * like add(), get(), clear() will be used).
* You probably wouldn't mock List class 'in real'. * * * * *

1. Let's verify some behaviour!

* *

 * //Let's import Mockito statically so that the code looks clearer
 * import static org.mockito.Mockito.*;
 *
 * //mock creation
 * List mockedList = mock(List.class);
 *
 * //using mock object
 * mockedList.add("one");
 * mockedList.clear();
 *
 * //verification
 * verify(mockedList).add("one");
 * verify(mockedList).clear();
 * 
* *

* Once created, mock will remember all interactions. Then you can selectively * verify whatever interaction you are interested in. * * * * *

2. How about some stubbing?

* *

 * //You can mock concrete classes, not only interfaces
 * LinkedList mockedList = mock(LinkedList.class);
 *
 * //stubbing
 * when(mockedList.get(0)).thenReturn("first");
 * when(mockedList.get(1)).thenThrow(new RuntimeException());
 *
 * //following prints "first"
 * System.out.println(mockedList.get(0));
 *
 * //following throws runtime exception
 * System.out.println(mockedList.get(1));
 *
 * //following prints "null" because get(999) was not stubbed
 * System.out.println(mockedList.get(999));
 *
 * //Although it is possible to verify a stubbed invocation, usually it's just redundant
 * //If your code cares what get(0) returns then something else breaks (often before even verify() gets executed).
 * //If your code doesn't care what get(0) returns then it should not be stubbed. Not convinced? See here.
 * verify(mockedList).get(0);
 * 
* *
    *
  • By default, for all methods that return value, mock returns null, an * empty collection or appropriate primitive/primitive wrapper value (e.g: 0, * false, ... for int/Integer, boolean/Boolean, ...).
  • * *
  • Stubbing can be overridden: for example common stubbing can go to * fixture setup but the test methods can override it. * Please note that overridding stubbing is a potential code smell that points out too much stubbing
  • * *
  • Once stubbed, the method will always return stubbed value regardless * of how many times it is called.
  • * *
  • Last stubbing is more important - when you stubbed the same method with * the same arguments many times. * Other words: the order of stubbing matters but it is only meaningful rarely, * e.g. when stubbing exactly the same method calls or sometimes when argument matchers are used, etc.
  • * *
* * * *

3. Argument matchers

* * Mockito verifies argument values in natural java style: by using an equals() method. * Sometimes, when extra flexibility is required then you might use argument matchers: * *

 * //stubbing using built-in anyInt() argument matcher
 * when(mockedList.get(anyInt())).thenReturn("element");
 *
 * //stubbing using hamcrest (let's say isValid() returns your own hamcrest matcher):
 * when(mockedList.contains(argThat(isValid()))).thenReturn("element");
 *
 * //following prints "element"
 * System.out.println(mockedList.get(999));
 *
 * //you can also verify using an argument matcher
 * verify(mockedList).get(anyInt());
 * 
* *

* Argument matchers allow flexible verification or stubbing. * {@link Matchers Click here to see} more built-in matchers * and examples of custom argument matchers / hamcrest matchers. *

* For information solely on custom argument matchers check out javadoc for {@link ArgumentMatcher} class. *

* Be reasonable with using complicated argument matching. * The natural matching style using equals() with occasional anyX() matchers tend to give clean & simple tests. * Sometimes it's just better to refactor the code to allow equals() matching or even implement equals() method to help out with testing. *

* Also, read section 15 or javadoc for {@link ArgumentCaptor} class. * {@link ArgumentCaptor} is a special implementation of an argument matcher that captures argument values for further assertions. *

* Warning on argument matchers: *

* If you are using argument matchers, all arguments have to be provided * by matchers. *

* E.g: (example shows verification but the same applies to stubbing): * *


 *   verify(mock).someMethod(anyInt(), anyString(), eq("third argument"));
 *   //above is correct - eq() is also an argument matcher
 *
 *   verify(mock).someMethod(anyInt(), anyString(), "third argument");
 *   //above is incorrect - exception will be thrown because third argument is given without an argument matcher.
 * 
* *

* Matcher methods like anyObject(), eq() do not return matchers. * Internally, they record a matcher on a stack and return a dummy value (usually null). * This implementation is due static type safety imposed by java compiler. * The consequence is that you cannot use anyObject(), eq() methods outside of verified/stubbed method. * * * * *

4. Verifying exact number of invocations / * at least x / never

* *

 * //using mock
 * mockedList.add("once");
 *
 * mockedList.add("twice");
 * mockedList.add("twice");
 *
 * mockedList.add("three times");
 * mockedList.add("three times");
 * mockedList.add("three times");
 *
 * //following two verifications work exactly the same - times(1) is used by default
 * verify(mockedList).add("once");
 * verify(mockedList, times(1)).add("once");
 *
 * //exact number of invocations verification
 * verify(mockedList, times(2)).add("twice");
 * verify(mockedList, times(3)).add("three times");
 *
 * //verification using never(). never() is an alias to times(0)
 * verify(mockedList, never()).add("never happened");
 *
 * //verification using atLeast()/atMost()
 * verify(mockedList, atLeastOnce()).add("three times");
 * verify(mockedList, atLeast(2)).add("five times");
 * verify(mockedList, atMost(5)).add("three times");
 *
 * 
* *

* times(1) is the default. Therefore using times(1) explicitly can be * omitted. * * * * *

5. Stubbing void methods with exceptions

* *

 *   doThrow(new RuntimeException()).when(mockedList).clear();
 *
 *   //following throws RuntimeException:
 *   mockedList.clear();
 * 
* * Read more about doThrow|doAnswer family of methods in paragraph 12. *

* Initially, {@link Mockito#stubVoid(Object)} was used for stubbing voids. * Currently stubVoid() is deprecated in favor of {@link Mockito#doThrow(Throwable)}. * This is because of improved readability and consistency with the family of {@link Mockito#doAnswer(Answer)} methods. * * * * *

6. Verification in order

* *

 * // A. Single mock whose methods must be invoked in a particular order
 * List singleMock = mock(List.class);
 *
 * //using a single mock
 * singleMock.add("was added first");
 * singleMock.add("was added second");
 *
 * //create an inOrder verifier for a single mock
 * InOrder inOrder = inOrder(singleMock);
 *
 * //following will make sure that add is first called with "was added first, then with "was added second"
 * inOrder.verify(singleMock).add("was added first");
 * inOrder.verify(singleMock).add("was added second");
 *
 * // B. Multiple mocks that must be used in a particular order
 * List firstMock = mock(List.class);
 * List secondMock = mock(List.class);
 *
 * //using mocks
 * firstMock.add("was called first");
 * secondMock.add("was called second");
 *
 * //create inOrder object passing any mocks that need to be verified in order
 * InOrder inOrder = inOrder(firstMock, secondMock);
 *
 * //following will make sure that firstMock was called before secondMock
 * inOrder.verify(firstMock).add("was called first");
 * inOrder.verify(secondMock).add("was called second");
 *
 * // Oh, and A + B can be mixed together at will
 * 
* * Verification in order is flexible - you don't have to verify all * interactions one-by-one but only those that you are interested in * testing in order. *

* Also, you can create InOrder object passing only mocks that are relevant for * in-order verification. * * * * *

7. Making sure interaction(s) never happened on mock

* *

 * //using mocks - only mockOne is interacted
 * mockOne.add("one");
 *
 * //ordinary verification
 * verify(mockOne).add("one");
 *
 * //verify that method was never called on a mock
 * verify(mockOne, never()).add("two");
 *
 * //verify that other mocks were not interacted
 * verifyZeroInteractions(mockTwo, mockThree);
 *
 * 
* * * * *

8. Finding redundant invocations

* *

 * //using mocks
 * mockedList.add("one");
 * mockedList.add("two");
 *
 * verify(mockedList).add("one");
 *
 * //following verification will fail
 * verifyNoMoreInteractions(mockedList);
 * 
* * A word of warning: * Some users who did a lot of classic, expect-run-verify mocking tend to use verifyNoMoreInteractions() very often, even in every test method. * verifyNoMoreInteractions() is not recommended to use in every test method. * verifyNoMoreInteractions() is a handy assertion from the interaction testing toolkit. Use it only when it's relevant. * Abusing it leads to overspecified, less maintainable tests. You can find further reading * here. * *

* See also {@link Mockito#never()} - it is more explicit and * communicates the intent well. *

* * * * *

9. Shorthand for mocks creation - @Mock annotation

* *
    *
  • Minimizes repetitive mock creation code.
  • *
  • Makes the test class more readable.
  • *
  • Makes the verification error easier to read because the field name * is used to identify the mock.
  • *
* *

 *   public class ArticleManagerTest {
 *
 *       @Mock private ArticleCalculator calculator;
 *       @Mock private ArticleDatabase database;
 *       @Mock private UserProvider userProvider;
 *
 *       private ArticleManager manager;
 * 
* * Important! This needs to be somewhere in the base class or a test * runner: * *

 * MockitoAnnotations.initMocks(testClass);
 * 
* * You can use built-in runner: {@link MockitoJUnitRunner} or a rule: {@link MockitoJUnitRule}. *

* Read more here: {@link MockitoAnnotations} * * * * *

10. Stubbing consecutive calls (iterator-style stubbing)

* * Sometimes we need to stub with different return value/exception for the same * method call. Typical use case could be mocking iterators. * Original version of Mockito did not have this feature to promote simple mocking. * For example, instead of iterators one could use {@link Iterable} or simply * collections. Those offer natural ways of stubbing (e.g. using real * collections). In rare scenarios stubbing consecutive calls could be useful, * though: *

* *


 * when(mock.someMethod("some arg"))
 *   .thenThrow(new RuntimeException())
 *   .thenReturn("foo");
 *
 * //First call: throws runtime exception:
 * mock.someMethod("some arg");
 *
 * //Second call: prints "foo"
 * System.out.println(mock.someMethod("some arg"));
 *
 * //Any consecutive call: prints "foo" as well (last stubbing wins).
 * System.out.println(mock.someMethod("some arg"));
 * 
* * Alternative, shorter version of consecutive stubbing: * *

 * when(mock.someMethod("some arg"))
 *   .thenReturn("one", "two", "three");
 * 
* * * * *

11. Stubbing with callbacks

* * Allows stubbing with generic {@link Answer} interface. *

* Yet another controversial feature which was not included in Mockito * originally. We recommend using simple stubbing with thenReturn() or * thenThrow() only. Those two should be just enough to test/test-drive * any clean & simple code. * *


 * when(mock.someMethod(anyString())).thenAnswer(new Answer() {
 *     Object answer(InvocationOnMock invocation) {
 *         Object[] args = invocation.getArguments();
 *         Object mock = invocation.getMock();
 *         return "called with arguments: " + args;
 *     }
 * });
 *
 * //Following prints "called with arguments: foo"
 * System.out.println(mock.someMethod("foo"));
 * 
* * * * *

12. doReturn()|doThrow()| * doAnswer()|doNothing()|doCallRealMethod() family of methods

* * Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler does not * like void methods inside brackets... *

* {@link Mockito#doThrow(Throwable)} replaces the {@link Mockito#stubVoid(Object)} method for stubbing voids. * The main reason is improved readability and consistency with the family of doAnswer() methods. *

* Use doThrow() when you want to stub a void method with an exception: *


 *   doThrow(new RuntimeException()).when(mockedList).clear();
 *
 *   //following throws RuntimeException:
 *   mockedList.clear();
 * 
* *

* You can use doThrow(), doAnswer(), doNothing(), doReturn() * and doCallRealMethod() in place of the corresponding call with when(), for any method. * It is necessary when you *

    *
  • stub void methods
  • *
  • stub methods on spy objects (see below)
  • *
  • stub the same method more than once, to change the behaviour of a mock in the middle of a test.
  • *
* but you may prefer to use these methods in place of the alternative with when(), for all of your stubbing calls. *

* Read more about these methods: *

* {@link Mockito#doReturn(Object)} *

* {@link Mockito#doThrow(Throwable)} *

* {@link Mockito#doThrow(Class)} *

* {@link Mockito#doAnswer(Answer)} *

* {@link Mockito#doNothing()} *

* {@link Mockito#doCallRealMethod()} * * * * *

13. Spying on real objects

* * You can create spies of real objects. When you use the spy then the real methods are called * (unless a method was stubbed). *

* Real spies should be used carefully and occasionally, for example when dealing with legacy code. * *

* Spying on real objects can be associated with "partial mocking" concept. * Before the release 1.8, Mockito spies were not real partial mocks. * The reason was we thought partial mock is a code smell. * At some point we found legitimate use cases for partial mocks * (3rd party interfaces, interim refactoring of legacy code, the full article is here) *

* *


 *   List list = new LinkedList();
 *   List spy = spy(list);
 *
 *   //optionally, you can stub out some methods:
 *   when(spy.size()).thenReturn(100);
 *
 *   //using the spy calls *real* methods
 *   spy.add("one");
 *   spy.add("two");
 *
 *   //prints "one" - the first element of a list
 *   System.out.println(spy.get(0));
 *
 *   //size() method was stubbed - 100 is printed
 *   System.out.println(spy.size());
 *
 *   //optionally, you can verify
 *   verify(spy).add("one");
 *   verify(spy).add("two");
 * 
* *

Important gotcha on spying real objects!

*
    *
  1. Sometimes it's impossible or impractical to use {@link Mockito#when(Object)} for stubbing spies. * Therefore when using spies please consider doReturn|Answer|Throw() family of * methods for stubbing. Example: * *
    
     *   List list = new LinkedList();
     *   List spy = spy(list);
     *
     *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
     *   when(spy.get(0)).thenReturn("foo");
     *
     *   //You have to use doReturn() for stubbing
     *   doReturn("foo").when(spy).get(0);
     * 
    *
  2. * *
  3. Mockito *does not* delegate calls to the passed real instance, instead it actually creates a copy of it. * So if you keep the real instance and interact with it, don't expect the spied to be aware of those interaction * and their effect on real instance state. * The corollary is that when an *unstubbed* method is called *on the spy* but *not on the real instance*, * you won't see any effects on the real instance. *
  4. * *
  5. Watch out for final methods. * Mockito doesn't mock final methods so the bottom line is: when you spy on real objects + you try to stub a final method = trouble. * Also you won't be able to verify those method as well. *
  6. *
* * * * *

14. Changing default return values of unstubbed invocations (Since 1.7)

* * You can create a mock with specified strategy for its return values. * It's quite advanced feature and typically you don't need it to write decent tests. * However, it can be helpful for working with legacy systems. *

* It is the default answer so it will be used only when you don't stub the method call. * *


 *   Foo mock = mock(Foo.class, Mockito.RETURNS_SMART_NULLS);
 *   Foo mockTwo = mock(Foo.class, new YourOwnAnswer());
 * 
* *

* Read more about this interesting implementation of Answer: {@link Mockito#RETURNS_SMART_NULLS} * * * * *

15. Capturing arguments for further assertions (Since 1.8.0)

* * Mockito verifies argument values in natural java style: by using an equals() method. * This is also the recommended way of matching arguments because it makes tests clean & simple. * In some situations though, it is helpful to assert on certain arguments after the actual verification. * For example: *

 *   ArgumentCaptor<Person> argument = ArgumentCaptor.forClass(Person.class);
 *   verify(mock).doSomething(argument.capture());
 *   assertEquals("John", argument.getValue().getName());
 * 
* * Warning: it is recommended to use ArgumentCaptor with verification but not with stubbing. * Using ArgumentCaptor with stubbing may decrease test readability because captor is created outside of assert (aka verify or 'then') block. * Also it may reduce defect localization because if stubbed method was not called then no argument is captured. *

* In a way ArgumentCaptor is related to custom argument matchers (see javadoc for {@link ArgumentMatcher} class). * Both techniques can be used for making sure certain arguments where passed to mocks. * However, ArgumentCaptor may be a better fit if: *

    *
  • custom argument matcher is not likely to be reused
  • *
  • you just need it to assert on argument values to complete verification
  • *
* Custom argument matchers via {@link ArgumentMatcher} are usually better for stubbing. * * * * *

16. Real partial mocks (Since 1.8.0)

* * Finally, after many internal debates & discussions on the mailing list, partial mock support was added to Mockito. * Previously we considered partial mocks as code smells. However, we found a legitimate use case for partial mocks - more reading: * here *

* Before release 1.8 spy() was not producing real partial mocks and it was confusing for some users. * Read more about spying: here or in javadoc for {@link Mockito#spy(Object)} method. *

*


 *    //you can create partial mock with spy() method:
 *    List list = spy(new LinkedList());
 *
 *    //you can enable partial mock capabilities selectively on mocks:
 *    Foo mock = mock(Foo.class);
 *    //Be sure the real implementation is 'safe'.
 *    //If real implementation throws exceptions or depends on specific state of the object then you're in trouble.
 *    when(mock.someMethod()).thenCallRealMethod();
 *  
* * As usual you are going to read the partial mock warning: * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects. * How does partial mock fit into this paradigm? Well, it just doesn't... * Partial mock usually means that the complexity has been moved to a different method on the same object. * In most cases, this is not the way you want to design your application. *

* However, there are rare cases when partial mocks come handy: * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.) * However, I wouldn't use partial mocks for new, test-driven & well-designed code. * * * * *

17. Resetting mocks (Since 1.8.0)

* * Smart Mockito users hardly use this feature because they know it could be a sign of poor tests. * Normally, you don't need to reset your mocks, just create new mocks for each test method. *

* Instead of reset() please consider writing simple, small and focused test methods over lengthy, over-specified tests. * First potential code smell is reset() in the middle of the test method. This probably means you're testing too much. * Follow the whisper of your test methods: "Please keep us small & focused on single behavior". * There are several threads about it on mockito mailing list. *

* The only reason we added reset() method is to * make it possible to work with container-injected mocks. * See issue 55 (here) * or FAQ (here). *

* Don't harm yourself. reset() in the middle of the test method is a code smell (you're probably testing too much). *


 *   List mock = mock(List.class);
 *   when(mock.size()).thenReturn(10);
 *   mock.add(1);
 *
 *   reset(mock);
 *   //at this point the mock forgot any interactions & stubbing
 * 
* * * * *

18. Troubleshooting & validating framework usage (Since 1.8.0)

* * First of all, in case of any trouble, I encourage you to read the Mockito FAQ: * http://code.google.com/p/mockito/wiki/FAQ *

* In case of questions you may also post to mockito mailing list: * http://groups.google.com/group/mockito *

* Next, you should know that Mockito validates if you use it correctly all the time. * However, there's a gotcha so please read the javadoc for {@link Mockito#validateMockitoUsage()} * * * * *

19. Aliases for behavior driven development (Since 1.8.0)

* * Behavior Driven Development style of writing tests uses //given //when //then comments as fundamental parts of your test methods. * This is exactly how we write our tests and we warmly encourage you to do so! *

* Start learning about BDD here: http://en.wikipedia.org/wiki/Behavior_Driven_Development *

* The problem is that current stubbing api with canonical role of when word does not integrate nicely with //given //when //then comments. * It's because stubbing belongs to given component of the test and not to the when component of the test. * Hence {@link BDDMockito} class introduces an alias so that you stub method calls with {@link BDDMockito#given(Object)} method. * Now it really nicely integrates with the given component of a BDD style test! *

* Here is how the test might look like: *


 * import static org.mockito.BDDMockito.*;
 *
 * Seller seller = mock(Seller.class);
 * Shop shop = new Shop(seller);
 *
 * public void shouldBuyBread() throws Exception {
 *   //given
 *   given(seller.askForBread()).willReturn(new Bread());
 *
 *   //when
 *   Goods goods = shop.buyBread();
 *
 *   //then
 *   assertThat(goods, containBread());
 * }
 * 
* * * * *

20. Serializable mocks (Since 1.8.1)

* * Mocks can be made serializable. With this feature you can use a mock in a place that requires dependencies to be serializable. *

* WARNING: This should be rarely used in unit testing. *

* The behaviour was implemented for a specific use case of a BDD spec that had an unreliable external dependency. This * was in a web environment and the objects from the external dependency were being serialized to pass between layers. *

* To create serializable mock use {@link MockSettings#serializable()}: *


 *   List serializableMock = mock(List.class, withSettings().serializable());
 * 
*

* The mock can be serialized assuming all the normal * serialization requirements are met by the class. *

* Making a real object spy serializable is a bit more effort as the spy(...) method does not have an overloaded version * which accepts MockSettings. No worries, you will hardly ever use it. * *


 * List<Object> list = new ArrayList<Object>();
 * List<Object> spy = mock(ArrayList.class, withSettings()
 *                 .spiedInstance(list)
 *                 .defaultAnswer(CALLS_REAL_METHODS)
 *                 .serializable());
 * 
* * * * *

21. New annotations: @Captor, * @Spy, * @InjectMocks (Since 1.8.3)

* *

* Release 1.8.3 brings new annotations that may be helpful on occasion: * *

    *
  • @{@link Captor} simplifies creation of {@link ArgumentCaptor} * - useful when the argument to capture is a nasty generic class and you want to avoid compiler warnings *
  • @{@link Spy} - you can use it instead {@link Mockito#spy(Object)}. *
  • @{@link InjectMocks} - injects mock or spy fields into tested object automatically. *
* *

* Note that @{@link InjectMocks} can also be used in combination with the @{@link Spy} annotation, it means * that Mockito will inject mocks into the partial mock under test. This complexity is another good reason why you * should only use partial mocks as a last resort. See point 16 about partial mocks. * *

* All new annotations are *only* processed on {@link MockitoAnnotations#initMocks(Object)}. * Just like for @{@link Mock} annotation you can use the built-in runner: {@link MockitoJUnitRunner} or rule: * {@link MockitoJUnitRule}. *

* * * * *

22. Verification with timeout (Since 1.8.5)

*

* Allows verifying with timeout. It causes a verify to wait for a specified period of time for a desired * interaction rather than fails immediately if had not already happened. May be useful for testing in concurrent * conditions. *

* It feels this feature should be used rarely - figure out a better way of testing your multi-threaded system. *

* Not yet implemented to work with InOrder verification. *

* Examples: *

*


 *   //passes when someMethod() is called within given time span
 *   verify(mock, timeout(100)).someMethod();
 *   //above is an alias to:
 *   verify(mock, timeout(100).times(1)).someMethod();
 *
 *   //passes when someMethod() is called *exactly* 2 times within given time span
 *   verify(mock, timeout(100).times(2)).someMethod();
 *
 *   //passes when someMethod() is called *at least* 2 times within given time span
 *   verify(mock, timeout(100).atLeast(2)).someMethod();
 *
 *   //verifies someMethod() within given time span using given verification mode
 *   //useful only if you have your own custom verification modes.
 *   verify(mock, new Timeout(100, yourOwnVerificationMode)).someMethod();
 * 
* * * * *

23. Automatic instantiation of @Spies, * @InjectMocks and constructor injection goodness (Since 1.9.0)

* *

* Mockito will now try to instantiate @{@link Spy} and will instantiate @{@link InjectMocks} fields * using constructor injection, setter injection, or field injection. *

* To take advantage of this feature you need to use {@link MockitoAnnotations#initMocks(Object)}, {@link MockitoJUnitRunner} * or {@link MockitoJUnitRule}. *

* Read more about available tricks and the rules of injection in the javadoc for {@link InjectMocks} *


 * //instead:
 * @Spy BeerDrinker drinker = new BeerDrinker();
 * //you can write:
 * @Spy BeerDrinker drinker;
 *
 * //same applies to @InjectMocks annotation:
 * @InjectMocks LocalPub;
 * 
* * * * *

24. One-liner stubs (Since 1.9.0)

*

* Mockito will now allow you to create mocks when stubbing. * Basically, it allows to create a stub in one line of code. * This can be helpful to keep test code clean. * For example, some boring stub can be created & stubbed at field initialization in a test: *


 * public class CarTest {
 *   Car boringStubbedCar = when(mock(Car.class).shiftGear()).thenThrow(EngineNotStarted.class).getMock();
 *
 *   @Test public void should... {}
 * 
* * * * *

25. Verification ignoring stubs (Since 1.9.0)

*

* Mockito will now allow to ignore stubbing for the sake of verification. * Sometimes useful when coupled with verifyNoMoreInteractions() or verification inOrder(). * Helps avoiding redundant verification of stubbed calls - typically we're not interested in verifying stubs. *

* Warning, ignoreStubs() might lead to overuse of verifyNoMoreInteractions(ignoreStubs(...)); * Bear in mind that Mockito does not recommend bombarding every test with verifyNoMoreInteractions() * for the reasons outlined in javadoc for {@link Mockito#verifyNoMoreInteractions(Object...)} *

Some examples: *


 * verify(mock).foo();
 * verify(mockTwo).bar();
 *
 * //ignores all stubbed methods:
 * verifyNoMoreInvocations(ignoreStubs(mock, mockTwo));
 *
 * //creates InOrder that will ignore stubbed
 * InOrder inOrder = inOrder(ignoreStubs(mock, mockTwo));
 * inOrder.verify(mock).foo();
 * inOrder.verify(mockTwo).bar();
 * inOrder.verifyNoMoreInteractions();
 * 
*

* Advanced examples and more details can be found in javadoc for {@link Mockito#ignoreStubs(Object...)} * * * * *

26. Mocking details (Since 1.9.5)

*

* To identify whether a particular object is a mock or a spy: *


 *     Mockito.mockingDetails(someObject).isMock();
 *     Mockito.mockingDetails(someObject).isSpy();
 * 
* Both the {@link MockingDetails#isMock} and {@link MockingDetails#isSpy()} methods return boolean. * As a spy is just a different kind of mock, isMock() returns true if the object is a spy. * In future Mockito versions MockingDetails may grow and provide other useful information about the mock, * e.g. invocations, stubbing info, etc. * * * * *

27. Delegate calls to real instance (Since 1.9.5)

* *

Useful for spies or partial mocks of objects that are difficult to mock or spy using the usual spy API. * Since Mockito 1.10.11, the delegate may or may not be of the same type as the mock. * If the type is different, a matching method needs to be found on delegate type otherwise an exception is thrown. * * Possible use cases for this feature: *

    *
  • Final classes but with an interface
  • *
  • Already custom proxied object
  • *
  • Special objects with a finalize method, i.e. to avoid executing it 2 times
  • *
* *

The difference with the regular spy: *

    *
  • * The regular spy ({@link #spy(Object)}) contains all state from the spied instance * and the methods are invoked on the spy. The spied instance is only used at mock creation to copy the state from. * If you call a method on a regular spy and it internally calls other methods on this spy, those calls are remembered * for verifications, and they can be effectively stubbed. *
  • *
  • * The mock that delegates simply delegates all methods to the delegate. * The delegate is used all the time as methods are delegated onto it. * If you call a method on a mock that delegates and it internally calls other methods on this mock, * those calls are not remembered for verifications, stubbing does not have effect on them, too. * Mock that delegates is less powerful than the regular spy but it is useful when the regular spy cannot be created. *
  • *
* *

* See more information in docs for {@link AdditionalAnswers#delegatesTo(Object)}. * * * * *

28. MockMaker API (Since 1.9.5)

*

Driven by requirements and patches from Google Android guys Mockito now offers an extension point * that allows replacing the proxy generation engine. By default, Mockito uses cglib to create dynamic proxies. *

The extension point is for advanced users that want to extend Mockito. For example, it is now possible * to use Mockito for Android testing with a help of dexmaker. *

For more details, motivations and examples please refer to * the docs for {@link org.mockito.plugins.MockMaker}. * * * * *

29. (new) BDD style verification (Since 1.10.0)

* * Enables Behavior Driven Development (BDD) style verification by starting verification with the BDD then keyword. * *

 *   then(person).should(times(2)).ride(bike);
 * 
* * For more information and an example see {@link BDDMockito#then(Object)}} * *

30. (new) Spying or mocking abstract classes (Since 1.10.12)

* * It is now possible to conveniently spy on abstract classes. Note that overusing spies hints at code design smells (see {@link #spy(Object)}). *

* Previously, spying was only possible on instances of objects. * New API makes it possible to use constructor when creating an instance of the mock. * This is particularly useful for mocking abstract classes because the user is no longer required to provide an instance of the abstract class. * At the moment, only parameter-less constructor is supported, let us know if it is not enough. * *


 *   //convenience API, new overloaded spy() method:
 *   SomeAbstract spy = spy(SomeAbstract.class);
 *
 *   //Robust API, via settings builder:
 *   OtherAbstract spy = mock(OtherAbstract.class, withSettings()
 *      .useConstructor().defaultAnswer(CALLS_REAL_METHODS));
 *
 *   //Mocking a non-static inner abstract class:
 *   InnerAbstract spy = mock(InnerAbstract.class, withSettings()
 *      .useConstructor().outerInstance(outerInstance).defaultAnswer(CALLS_REAL_METHODS));
 * 
* * For more information please see {@link MockSettings#useConstructor()}. */ @SuppressWarnings("unchecked") public class Mockito extends Matchers { static final MockitoCore MOCKITO_CORE = new MockitoCore(); /** * The default Answer of every mock if the mock was not stubbed. * Typically it just returns some empty value. *

* {@link Answer} can be used to define the return values of unstubbed invocations. *

* This implementation first tries the global configuration. * If there is no global configuration then it uses {@link ReturnsEmptyValues} (returns zeros, empty collections, nulls, etc.) */ public static final Answer RETURNS_DEFAULTS = Answers.RETURNS_DEFAULTS.get(); /** * Optional Answer to be used with {@link Mockito#mock(Class, Answer)}. *

* {@link Answer} can be used to define the return values of unstubbed invocations. *

* This implementation can be helpful when working with legacy code. * Unstubbed methods often return null. If your code uses the object returned by an unstubbed call you get a NullPointerException. * This implementation of Answer returns SmartNull instead of null. * SmartNull gives nicer exception message than NPE because it points out the line where unstubbed method was called. You just click on the stack trace. *

* ReturnsSmartNulls first tries to return ordinary return values (see {@link ReturnsMoreEmptyValues}) * then it tries to return SmartNull. If the return type is final then plain null is returned. *

* ReturnsSmartNulls will be probably the default return values strategy in Mockito 2.0. *

* Example: *


     *   Foo mock = (Foo.class, RETURNS_SMART_NULLS);
     *
     *   //calling unstubbed method here:
     *   Stuff stuff = mock.getStuff();
     *
     *   //using object returned by unstubbed call:
     *   stuff.doSomething();
     *
     *   //Above doesn't yield NullPointerException this time!
     *   //Instead, SmartNullPointerException is thrown.
     *   //Exception's cause links to unstubbed mock.getStuff() - just click on the stack trace.
     * 
*/ public static final Answer RETURNS_SMART_NULLS = Answers.RETURNS_SMART_NULLS.get(); /** * Optional Answer to be used with {@link Mockito#mock(Class, Answer)} *

* {@link Answer} can be used to define the return values of unstubbed invocations. *

* This implementation can be helpful when working with legacy code. *

* ReturnsMocks first tries to return ordinary return values (see {@link ReturnsMoreEmptyValues}) * then it tries to return mocks. If the return type cannot be mocked (e.g. is final) then plain null is returned. *

*/ public static final Answer RETURNS_MOCKS = Answers.RETURNS_MOCKS.get(); /** * Optional Answer to be used with {@link Mockito#mock(Class, Answer)}. *

* Example that shows how deep stub works: *


     *   Foo mock = mock(Foo.class, RETURNS_DEEP_STUBS);
     *
     *   // note that we're stubbing a chain of methods here: getBar().getName()
     *   when(mock.getBar().getName()).thenReturn("deep");
     *
     *   // note that we're chaining method calls: getBar().getName()
     *   assertEquals("deep", mock.getBar().getName());
     * 
*

* *

* WARNING: * This feature should rarely be required for regular clean code! Leave it for legacy code. * Mocking a mock to return a mock, to return a mock, (...), to return something meaningful * hints at violation of Law of Demeter or mocking a value object (a well known anti-pattern). *

* *

* Good quote I've seen one day on the web: every time a mock returns a mock a fairy dies. *

* *

* Please note that this answer will return existing mocks that matches the stub. This * behavior is ok with deep stubs and allows verification to work on the last mock of the chain. *


     *   when(mock.getBar(anyString()).getThingy().getName()).thenReturn("deep");
     *
     *   mock.getBar("candy bar").getThingy().getName();
     *
     *   assertSame(mock.getBar(anyString()).getThingy().getName(), mock.getBar(anyString()).getThingy().getName());
     *   verify(mock.getBar("candy bar").getThingy()).getName();
     *   verify(mock.getBar(anyString()).getThingy()).getName();
     * 
*

* *

* Verification only works with the last mock in the chain. You can use verification modes. *


     *   when(person.getAddress(anyString()).getStreet().getName()).thenReturn("deep");
     *   when(person.getAddress(anyString()).getStreet(Locale.ITALIAN).getName()).thenReturn("deep");
     *   when(person.getAddress(anyString()).getStreet(Locale.CHINESE).getName()).thenReturn("deep");
     *
     *   person.getAddress("the docks").getStreet().getName();
     *   person.getAddress("the docks").getStreet().getLongName();
     *   person.getAddress("the docks").getStreet(Locale.ITALIAN).getName();
     *   person.getAddress("the docks").getStreet(Locale.CHINESE).getName();
     *
     *   // note that we are actually referring to the very last mock in the stubbing chain.
     *   InOrder inOrder = inOrder(
     *       person.getAddress("the docks").getStreet(),
     *       person.getAddress("the docks").getStreet(Locale.CHINESE),
     *       person.getAddress("the docks").getStreet(Locale.ITALIAN)
     *   );
     *   inOrder.verify(person.getAddress("the docks").getStreet(), times(1)).getName();
     *   inOrder.verify(person.getAddress("the docks").getStreet()).getLongName();
     *   inOrder.verify(person.getAddress("the docks").getStreet(Locale.ITALIAN), atLeast(1)).getName();
     *   inOrder.verify(person.getAddress("the docks").getStreet(Locale.CHINESE)).getName();
     * 
*

* *

* How deep stub work internally? *


     *   //this:
     *   Foo mock = mock(Foo.class, RETURNS_DEEP_STUBS);
     *   when(mock.getBar().getName(), "deep");
     *
     *   //is equivalent of
     *   Foo foo = mock(Foo.class);
     *   Bar bar = mock(Bar.class);
     *   when(foo.getBar()).thenReturn(bar);
     *   when(bar.getName()).thenReturn("deep");
     * 
*

* *

* This feature will not work when any return type of methods included in the chain cannot be mocked * (for example: is a primitive or a final class). This is because of java type system. *

*/ public static final Answer RETURNS_DEEP_STUBS = Answers.RETURNS_DEEP_STUBS.get(); /** * Optional Answer to be used with {@link Mockito#mock(Class, Answer)} *

* {@link Answer} can be used to define the return values of unstubbed invocations. *

* This implementation can be helpful when working with legacy code. * When this implementation is used, unstubbed methods will delegate to the real implementation. * This is a way to create a partial mock object that calls real methods by default. *

* As usual you are going to read the partial mock warning: * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects. * How does partial mock fit into this paradigm? Well, it just doesn't... * Partial mock usually means that the complexity has been moved to a different method on the same object. * In most cases, this is not the way you want to design your application. *

* However, there are rare cases when partial mocks come handy: * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.) * However, I wouldn't use partial mocks for new, test-driven & well-designed code. *

* Example: *


     * Foo mock = mock(Foo.class, CALLS_REAL_METHODS);
     *
     * // this calls the real implementation of Foo.getSomething()
     * value = mock.getSomething();
     *
     * when(mock.getSomething()).thenReturn(fakeValue);
     *
     * // now fakeValue is returned
     * value = mock.getSomething();
     * 
*/ public static final Answer CALLS_REAL_METHODS = Answers.CALLS_REAL_METHODS.get(); /** * Creates mock object of given class or interface. *

* See examples in javadoc for {@link Mockito} class * * @param classToMock class or interface to mock * @return mock object */ public static T mock(Class classToMock) { return mock(classToMock, withSettings().defaultAnswer(RETURNS_DEFAULTS)); } /** * Specifies mock name. Naming mocks can be helpful for debugging - the name is used in all verification errors. *

* Beware that naming mocks is not a solution for complex code which uses too many mocks or collaborators. * If you have too many mocks then refactor the code so that it's easy to test/debug without necessity of naming mocks. *

* If you use @Mock annotation then you've got naming mocks for free! @Mock uses field name as mock name. {@link Mock Read more.} *

* * See examples in javadoc for {@link Mockito} class * * @param classToMock class or interface to mock * @param name of the mock * @return mock object */ public static T mock(Class classToMock, String name) { return mock(classToMock, withSettings() .name(name) .defaultAnswer(RETURNS_DEFAULTS)); } /** * Returns a MockingDetails instance that enables inspecting a particular object for Mockito related information. * Can be used to find out if given object is a Mockito mock * or to find out if a given mock is a spy or mock. *

* In future Mockito versions MockingDetails may grow and provide other useful information about the mock, * e.g. invocations, stubbing info, etc. * * @param toInspect - object to inspect. null input is allowed. * @return A {@link org.mockito.MockingDetails} instance. * @since 1.9.5 */ public static MockingDetails mockingDetails(Object toInspect) { return MOCKITO_CORE.mockingDetails(toInspect); } /** * Deprecated : Please use mock(Foo.class, defaultAnswer); *

* See {@link Mockito#mock(Class, Answer)} *

* Why it is deprecated? ReturnValues is being replaced by Answer * for better consistency & interoperability of the framework. * Answer interface has been in Mockito for a while and it has the same responsibility as ReturnValues. * There's no point in mainting exactly the same interfaces. *

* Creates mock with a specified strategy for its return values. * It's quite advanced feature and typically you don't need it to write decent tests. * However it can be helpful when working with legacy systems. *

* Obviously return values are used only when you don't stub the method call. * *


     *   Foo mock = mock(Foo.class, Mockito.RETURNS_SMART_NULLS);
     *   Foo mockTwo = mock(Foo.class, new YourOwnReturnValues());
     * 
* *

See examples in javadoc for {@link Mockito} class

* * @param classToMock class or interface to mock * @param returnValues default return values for unstubbed methods * * @return mock object * * @deprecated Please use mock(Foo.class, defaultAnswer); */ @Deprecated public static T mock(Class classToMock, ReturnValues returnValues) { return mock(classToMock, withSettings().defaultAnswer(new AnswerReturnValuesAdapter(returnValues))); } /** * Creates mock with a specified strategy for its answers to interactions. * It's quite advanced feature and typically you don't need it to write decent tests. * However it can be helpful when working with legacy systems. *

* It is the default answer so it will be used only when you don't stub the method call. * *


     *   Foo mock = mock(Foo.class, RETURNS_SMART_NULLS);
     *   Foo mockTwo = mock(Foo.class, new YourOwnAnswer());
     * 
* *

See examples in javadoc for {@link Mockito} class

* * @param classToMock class or interface to mock * @param defaultAnswer default answer for unstubbed methods * * @return mock object */ public static T mock(Class classToMock, Answer defaultAnswer) { return mock(classToMock, withSettings().defaultAnswer(defaultAnswer)); } /** * Creates a mock with some non-standard settings. *

* The number of configuration points for a mock grows * so we need a fluent way to introduce new configuration without adding more and more overloaded Mockito.mock() methods. * Hence {@link MockSettings}. *


     *   Listener mock = mock(Listener.class, withSettings()
     *     .name("firstListner").defaultBehavior(RETURNS_SMART_NULLS));
     *   );
     * 
* Use it carefully and occasionally. What might be reason your test needs non-standard mocks? * Is the code under test so complicated that it requires non-standard mocks? * Wouldn't you prefer to refactor the code under test so it is testable in a simple way? *

* See also {@link Mockito#withSettings()} *

* See examples in javadoc for {@link Mockito} class * * @param classToMock class or interface to mock * @param mockSettings additional mock settings * @return mock object */ public static T mock(Class classToMock, MockSettings mockSettings) { return MOCKITO_CORE.mock(classToMock, mockSettings); } /** * Creates a spy of the real object. The spy calls real methods unless they are stubbed. *

* Real spies should be used carefully and occasionally, for example when dealing with legacy code. *

* As usual you are going to read the partial mock warning: * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects. * How does partial mock fit into this paradigm? Well, it just doesn't... * Partial mock usually means that the complexity has been moved to a different method on the same object. * In most cases, this is not the way you want to design your application. *

* However, there are rare cases when partial mocks come handy: * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.) * However, I wouldn't use partial mocks for new, test-driven & well-designed code. *

* Example: * *


     *   List list = new LinkedList();
     *   List spy = spy(list);
     *
     *   //optionally, you can stub out some methods:
     *   when(spy.size()).thenReturn(100);
     *
     *   //using the spy calls real methods
     *   spy.add("one");
     *   spy.add("two");
     *
     *   //prints "one" - the first element of a list
     *   System.out.println(spy.get(0));
     *
     *   //size() method was stubbed - 100 is printed
     *   System.out.println(spy.size());
     *
     *   //optionally, you can verify
     *   verify(spy).add("one");
     *   verify(spy).add("two");
     * 
* *

Important gotcha on spying real objects!

*
    *
  1. Sometimes it's impossible or impractical to use {@link Mockito#when(Object)} for stubbing spies. * Therefore for spies it is recommended to always use doReturn|Answer|Throw()|CallRealMethod * family of methods for stubbing. Example: * *
    
         *   List list = new LinkedList();
         *   List spy = spy(list);
         *
         *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
         *   when(spy.get(0)).thenReturn("foo");
         *
         *   //You have to use doReturn() for stubbing
         *   doReturn("foo").when(spy).get(0);
         * 
    *
  2. * *
  3. Mockito *does not* delegate calls to the passed real instance, instead it actually creates a copy of it. * So if you keep the real instance and interact with it, don't expect the spied to be aware of those interaction * and their effect on real instance state. * The corollary is that when an *unstubbed* method is called *on the spy* but *not on the real instance*, * you won't see any effects on the real instance.
  4. * *
  5. Watch out for final methods. * Mockito doesn't mock final methods so the bottom line is: when you spy on real objects + you try to stub a final method = trouble. * Also you won't be able to verify those method as well. *
  6. *
*

* See examples in javadoc for {@link Mockito} class * *

Note that the spy won't have any annotations of the spied type, because CGLIB won't rewrite them. * It may troublesome for code that rely on the spy to have these annotations.

* * * @param object * to spy on * @return a spy of the real object */ public static T spy(T object) { return MOCKITO_CORE.mock((Class) object.getClass(), withSettings() .spiedInstance(object) .defaultAnswer(CALLS_REAL_METHODS)); } /** * Please refer to the documentation of {@link #spy(Object)}. * Overusing spies hints at code design smells. *

* This method, in contrast to the original {@link #spy(Object)}, creates a spy based on class instead of an object. * Sometimes it is more convenient to create spy based on the class and avoid providing an instance of a spied object. * This is particularly useful for spying on abstract classes because they cannot be instantiated. * See also {@link MockSettings#useConstructor()}. *

* Examples: *


     *   SomeAbstract spy = spy(SomeAbstract.class);
     *
     *   //Robust API, via settings builder:
     *   OtherAbstract spy = mock(OtherAbstract.class, withSettings()
     *      .useConstructor().defaultAnswer(CALLS_REAL_METHODS));
     *
     *   //Mocking a non-static inner abstract class:
     *   InnerAbstract spy = mock(InnerAbstract.class, withSettings()
     *      .useConstructor().outerInstance(outerInstance).defaultAnswer(CALLS_REAL_METHODS));
     * 
* * @param classToSpy the class to spy * @param type of the spy * @return a spy of the provided class * @since 1.10.12 */ @Incubating public static T spy(Class classToSpy) { return MOCKITO_CORE.mock(classToSpy, withSettings() .useConstructor() .defaultAnswer(CALLS_REAL_METHODS)); } /** * Stubs a method call with return value or an exception. E.g: * *

     * stub(mock.someMethod()).toReturn(10);
     *
     * //you can use flexible argument matchers, e.g:
     * stub(mock.someMethod(anyString())).toReturn(10);
     *
     * //setting exception to be thrown:
     * stub(mock.someMethod("some arg")).toThrow(new RuntimeException());
     *
     * //you can stub with different behavior for consecutive method calls.
     * //Last stubbing (e.g: toReturn("foo")) determines the behavior for further consecutive calls.
     * stub(mock.someMethod("some arg"))
     *  .toThrow(new RuntimeException())
     *  .toReturn("foo");
     * 
*

* Some users find stub() confusing therefore {@link Mockito#when(Object)} is recommended over stub() *


     *   //Instead of:
     *   stub(mock.count()).toReturn(10);
     *
     *   //You can do:
     *   when(mock.count()).thenReturn(10);
     * 
* For stubbing void methods with throwables see: {@link Mockito#doThrow(Throwable)} *

* Stubbing can be overridden: for example common stubbing can go to fixture * setup but the test methods can override it. * Please note that overridding stubbing is a potential code smell that points out too much stubbing. *

* Once stubbed, the method will always return stubbed value regardless * of how many times it is called. *

* Last stubbing is more important - when you stubbed the same method with * the same arguments many times. *

* Although it is possible to verify a stubbed invocation, usually it's just redundant. * Let's say you've stubbed foo.bar(). * If your code cares what foo.bar() returns then something else breaks(often before even verify() gets executed). * If your code doesn't care what get(0) returns then it should not be stubbed. * Not convinced? See here. * * @param methodCall * method call * @return DeprecatedOngoingStubbing object to set stubbed value/exception */ public static DeprecatedOngoingStubbing stub(T methodCall) { return MOCKITO_CORE.stub(methodCall); } /** * Enables stubbing methods. Use it when you want the mock to return particular value when particular method is called. *

* Simply put: "When the x method is called then return y". *

* when() is a successor of deprecated {@link Mockito#stub(Object)} *

* Examples: * *


     * when(mock.someMethod()).thenReturn(10);
     *
     * //you can use flexible argument matchers, e.g:
     * when(mock.someMethod(anyString())).thenReturn(10);
     *
     * //setting exception to be thrown:
     * when(mock.someMethod("some arg")).thenThrow(new RuntimeException());
     *
     * //you can set different behavior for consecutive method calls.
     * //Last stubbing (e.g: thenReturn("foo")) determines the behavior of further consecutive calls.
     * when(mock.someMethod("some arg"))
     *  .thenThrow(new RuntimeException())
     *  .thenReturn("foo");
     *
     * //Alternative, shorter version for consecutive stubbing:
     * when(mock.someMethod("some arg"))
     *  .thenReturn("one", "two");
     * //is the same as:
     * when(mock.someMethod("some arg"))
     *  .thenReturn("one")
     *  .thenReturn("two");
     *
     * //shorter version for consecutive method calls throwing exceptions:
     * when(mock.someMethod("some arg"))
     *  .thenThrow(new RuntimeException(), new NullPointerException();
     *
     * 
* * For stubbing void methods with throwables see: {@link Mockito#doThrow(Throwable)} *

* Stubbing can be overridden: for example common stubbing can go to fixture * setup but the test methods can override it. * Please note that overridding stubbing is a potential code smell that points out too much stubbing. *

* Once stubbed, the method will always return stubbed value regardless * of how many times it is called. *

* Last stubbing is more important - when you stubbed the same method with * the same arguments many times. *

* Although it is possible to verify a stubbed invocation, usually it's just redundant. * Let's say you've stubbed foo.bar(). * If your code cares what foo.bar() returns then something else breaks(often before even verify() gets executed). * If your code doesn't care what get(0) returns then it should not be stubbed. * Not convinced? See here. * *

* See examples in javadoc for {@link Mockito} class * @param methodCall method to be stubbed * @return OngoingStubbing object used to stub fluently. * Do not create a reference to this returned object. */ public static OngoingStubbing when(T methodCall) { return MOCKITO_CORE.when(methodCall); } /** * Verifies certain behavior happened once. *

* Alias to verify(mock, times(1)) E.g: *


     *   verify(mock).someMethod("some arg");
     * 
* Above is equivalent to: *

     *   verify(mock, times(1)).someMethod("some arg");
     * 
*

* Arguments passed are compared using equals() method. * Read about {@link ArgumentCaptor} or {@link ArgumentMatcher} to find out other ways of matching / asserting arguments passed. *

* Although it is possible to verify a stubbed invocation, usually it's just redundant. * Let's say you've stubbed foo.bar(). * If your code cares what foo.bar() returns then something else breaks(often before even verify() gets executed). * If your code doesn't care what get(0) returns then it should not be stubbed. * Not convinced? See here. * *

* See examples in javadoc for {@link Mockito} class * * @param mock to be verified * @return mock object itself */ public static T verify(T mock) { return MOCKITO_CORE.verify(mock, times(1)); } /** * Verifies certain behavior happened at least once / exact number of times / never. E.g: *


     *   verify(mock, times(5)).someMethod("was called five times");
     *
     *   verify(mock, atLeast(2)).someMethod("was called at least two times");
     *
     *   //you can use flexible argument matchers, e.g:
     *   verify(mock, atLeastOnce()).someMethod(anyString());
     * 
* * times(1) is the default and can be omitted *

* Arguments passed are compared using equals() method. * Read about {@link ArgumentCaptor} or {@link ArgumentMatcher} to find out other ways of matching / asserting arguments passed. *

* * @param mock to be verified * @param mode times(x), atLeastOnce() or never() * * @return mock object itself */ public static T verify(T mock, VerificationMode mode) { return MOCKITO_CORE.verify(mock, mode); } /** * Smart Mockito users hardly use this feature because they know it could be a sign of poor tests. * Normally, you don't need to reset your mocks, just create new mocks for each test method. *

* Instead of #reset() please consider writing simple, small and focused test methods over lengthy, over-specified tests. * First potential code smell is reset() in the middle of the test method. This probably means you're testing too much. * Follow the whisper of your test methods: "Please keep us small & focused on single behavior". * There are several threads about it on mockito mailing list. *

* The only reason we added reset() method is to * make it possible to work with container-injected mocks. * See issue 55 (here) * or FAQ (here). *

* Don't harm yourself. reset() in the middle of the test method is a code smell (you're probably testing too much). *


     *   List mock = mock(List.class);
     *   when(mock.size()).thenReturn(10);
     *   mock.add(1);
     *
     *   reset(mock);
     *   //at this point the mock forgot any interactions & stubbing
     * 
* * @param The Type of the mocks * @param mocks to be reset */ public static void reset(T ... mocks) { MOCKITO_CORE.reset(mocks); } /** * Checks if any of given mocks has any unverified interaction. *

* You can use this method after you verified your mocks - to make sure that nothing * else was invoked on your mocks. *

* See also {@link Mockito#never()} - it is more explicit and communicates the intent well. *

* Stubbed invocations (if called) are also treated as interactions. *

* A word of warning: * Some users who did a lot of classic, expect-run-verify mocking tend to use verifyNoMoreInteractions() very often, even in every test method. * verifyNoMoreInteractions() is not recommended to use in every test method. * verifyNoMoreInteractions() is a handy assertion from the interaction testing toolkit. Use it only when it's relevant. * Abusing it leads to overspecified, less maintainable tests. You can find further reading * here. *

* This method will also detect unverified invocations that occurred before the test method, * for example: in setUp(), @Before method or in constructor. * Consider writing nice code that makes interactions only in test methods. * *

* Example: * *


     * //interactions
     * mock.doSomething();
     * mock.doSomethingUnexpected();
     *
     * //verification
     * verify(mock).doSomething();
     *
     * //following will fail because 'doSomethingUnexpected()' is unexpected
     * verifyNoMoreInteractions(mock);
     *
     * 
* * See examples in javadoc for {@link Mockito} class * * @param mocks to be verified */ public static void verifyNoMoreInteractions(Object... mocks) { MOCKITO_CORE.verifyNoMoreInteractions(mocks); } /** * Verifies that no interactions happened on given mocks. *

     *   verifyZeroInteractions(mockOne, mockTwo);
     * 
* This method will also detect invocations * that occurred before the test method, for example: in setUp(), @Before method or in constructor. * Consider writing nice code that makes interactions only in test methods. *

* See also {@link Mockito#never()} - it is more explicit and communicates the intent well. *

* See examples in javadoc for {@link Mockito} class * * @param mocks to be verified */ public static void verifyZeroInteractions(Object... mocks) { MOCKITO_CORE.verifyNoMoreInteractions(mocks); } /** *


     *   //Instead of:
     *   stubVoid(mock).toThrow(e).on().someVoidMethod();
     *
     *   //Please do:
     *   doThrow(e).when(mock).someVoidMethod();
     * 
* * doThrow() replaces stubVoid() because of improved readability and consistency with the family of doAnswer() methods. *

* Originally, stubVoid() was used for stubbing void methods with exceptions. E.g: * *


     * stubVoid(mock).toThrow(new RuntimeException()).on().someMethod();
     *
     * //you can stub with different behavior for consecutive calls.
     * //Last stubbing (e.g. toReturn()) determines the behavior for further consecutive calls.
     * stubVoid(mock)
     *   .toThrow(new RuntimeException())
     *   .toReturn()
     *   .on().someMethod();
     * 
* * See examples in javadoc for {@link Mockito} class * * @deprecated Use {@link Mockito#doThrow(Throwable)} method for stubbing voids * * @param mock * to stub * @return stubbable object that allows stubbing with throwable */ public static VoidMethodStubbable stubVoid(T mock) { return MOCKITO_CORE.stubVoid(mock); } /** * Use doThrow() when you want to stub the void method with an exception. *

* Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler does not like void methods inside brackets... *

* Example: * *


     *   doThrow(new RuntimeException()).when(mock).someVoidMethod();
     * 
* * @param toBeThrown to be thrown when the stubbed method is called * @return stubber - to select a method for stubbing */ public static Stubber doThrow(Throwable toBeThrown) { return MOCKITO_CORE.doAnswer(new ThrowsException(toBeThrown)); } /** * Use doThrow() when you want to stub the void method to throw exception of specified class. *

* A new exception instance will be created for each method invocation. *

* Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler does not like void methods inside brackets... *

* Example: * *


     *   doThrow(RuntimeException.class).when(mock).someVoidMethod();
     * 
* * @param toBeThrown to be thrown when the stubbed method is called * @return stubber - to select a method for stubbing * @since 1.9.0 */ public static Stubber doThrow(Class toBeThrown) { return MOCKITO_CORE.doAnswer(new ThrowsExceptionClass(toBeThrown)); } /** * Use doCallRealMethod() when you want to call the real implementation of a method. *

* As usual you are going to read the partial mock warning: * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects. * How does partial mock fit into this paradigm? Well, it just doesn't... * Partial mock usually means that the complexity has been moved to a different method on the same object. * In most cases, this is not the way you want to design your application. *

* However, there are rare cases when partial mocks come handy: * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.) * However, I wouldn't use partial mocks for new, test-driven & well-designed code. *

* See also javadoc {@link Mockito#spy(Object)} to find out more about partial mocks. * Mockito.spy() is a recommended way of creating partial mocks. * The reason is it guarantees real methods are called against correctly constructed object because you're responsible for constructing the object passed to spy() method. *

* Example: *


     *   Foo mock = mock(Foo.class);
     *   doCallRealMethod().when(mock).someVoidMethod();
     *
     *   // this will call the real implementation of Foo.someVoidMethod()
     *   mock.someVoidMethod();
     * 
*

* See examples in javadoc for {@link Mockito} class * * @return stubber - to select a method for stubbing * @since 1.9.5 */ public static Stubber doCallRealMethod() { return MOCKITO_CORE.doAnswer(new CallsRealMethods()); } /** * Use doAnswer() when you want to stub a void method with generic {@link Answer}. *

* Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler does not like void methods inside brackets... *

* Example: * *


     *  doAnswer(new Answer() {
     *      public Object answer(InvocationOnMock invocation) {
     *          Object[] args = invocation.getArguments();
     *          Mock mock = invocation.getMock();
     *          return null;
     *      }})
     *  .when(mock).someMethod();
     * 
*

* See examples in javadoc for {@link Mockito} class * * @param answer to answer when the stubbed method is called * @return stubber - to select a method for stubbing */ public static Stubber doAnswer(Answer answer) { return MOCKITO_CORE.doAnswer(answer); } /** * Use doNothing() for setting void methods to do nothing. Beware that void methods on mocks do nothing by default! * However, there are rare situations when doNothing() comes handy: *

*

    *
  1. Stubbing consecutive calls on a void method: *
    
         *   doNothing().
         *   doThrow(new RuntimeException())
         *   .when(mock).someVoidMethod();
         *
         *   //does nothing the first time:
         *   mock.someVoidMethod();
         *
         *   //throws RuntimeException the next time:
         *   mock.someVoidMethod();
         * 
    *
  2. *
  3. When you spy real objects and you want the void method to do nothing: *
    
         *   List list = new LinkedList();
         *   List spy = spy(list);
         *
         *   //let's make clear() do nothing
         *   doNothing().when(spy).clear();
         *
         *   spy.add("one");
         *
         *   //clear() does nothing, so the list still contains "one"
         *   spy.clear();
         * 
    *
  4. *
*

* See examples in javadoc for {@link Mockito} class * * @return stubber - to select a method for stubbing */ public static Stubber doNothing() { return MOCKITO_CORE.doAnswer(new DoesNothing()); } /** * Use doReturn() in those rare occasions when you cannot use {@link Mockito#when(Object)}. *

* Beware that {@link Mockito#when(Object)} is always recommended for stubbing because it is argument type-safe * and more readable (especially when stubbing consecutive calls). *

* Here are those rare occasions when doReturn() comes handy: *

* *

    *
  1. When spying real objects and calling real methods on a spy brings side effects * *
    
         *   List list = new LinkedList();
         *   List spy = spy(list);
         *
         *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
         *   when(spy.get(0)).thenReturn("foo");
         *
         *   //You have to use doReturn() for stubbing:
         *   doReturn("foo").when(spy).get(0);
         * 
    *
  2. * *
  3. Overriding a previous exception-stubbing: *
    
         *   when(mock.foo()).thenThrow(new RuntimeException());
         *
         *   //Impossible: the exception-stubbed foo() method is called so RuntimeException is thrown.
         *   when(mock.foo()).thenReturn("bar");
         *
         *   //You have to use doReturn() for stubbing:
         *   doReturn("bar").when(mock).foo();
         * 
    *
  4. *
* * Above scenarios shows a tradeoff of Mockito's elegant syntax. Note that the scenarios are very rare, though. * Spying should be sporadic and overriding exception-stubbing is very rare. Not to mention that in general * overridding stubbing is a potential code smell that points out too much stubbing. *

* See examples in javadoc for {@link Mockito} class * * @param toBeReturned to be returned when the stubbed method is called * @return stubber - to select a method for stubbing */ public static Stubber doReturn(Object toBeReturned) { return MOCKITO_CORE.doAnswer(new Returns(toBeReturned)); } /** * Creates {@link org.mockito.InOrder} object that allows verifying mocks in order. * *


     *   InOrder inOrder = inOrder(firstMock, secondMock);
     *
     *   inOrder.verify(firstMock).add("was called first");
     *   inOrder.verify(secondMock).add("was called second");
     * 
* * Verification in order is flexible - you don't have to verify all interactions one-by-one * but only those that you are interested in testing in order. *

* Also, you can create InOrder object passing only mocks that are relevant for in-order verification. *

* InOrder verification is 'greedy'. You will hardly every notice it but * if you want to find out more search for 'greedy' on the Mockito * wiki pages. *

* As of Mockito 1.8.4 you can verifyNoMoreInvocations() in order-sensitive way. Read more: {@link InOrder#verifyNoMoreInteractions()} *

* See examples in javadoc for {@link Mockito} class * * @param mocks to be verified in order * * @return InOrder object to be used to verify in order */ public static InOrder inOrder(Object... mocks) { return MOCKITO_CORE.inOrder(mocks); } /** * Ignores stubbed methods of given mocks for the sake of verification. * Sometimes useful when coupled with verifyNoMoreInteractions() or verification inOrder(). * Helps avoiding redundant verification of stubbed calls - typically we're not interested in verifying stubs. *

* Warning, ignoreStubs() might lead to overuse of verifyNoMoreInteractions(ignoreStubs(...)); * Bear in mind that Mockito does not recommend bombarding every test with verifyNoMoreInteractions() * for the reasons outlined in javadoc for {@link Mockito#verifyNoMoreInteractions(Object...)} * Other words: all *stubbed* methods of given mocks are marked *verified* so that they don't get in a way during verifyNoMoreInteractions(). *

* This method changes the input mocks! This method returns input mocks just for convenience. *

* Ignored stubs will also be ignored for verification inOrder, including {@link org.mockito.InOrder#verifyNoMoreInteractions()}. * See the second example. *

* Example: *


     *  //mocking lists for the sake of the example (if you mock List in real you will burn in hell)
     *  List mock1 = mock(List.class), mock2 = mock(List.class);
     *
     *  //stubbing mocks:
     *  when(mock1.get(0)).thenReturn(10);
     *  when(mock2.get(0)).thenReturn(20);
     *
     *  //using mocks by calling stubbed get(0) methods:
     *  System.out.println(mock1.get(0)); //prints 10
     *  System.out.println(mock2.get(0)); //prints 20
     *
     *  //using mocks by calling clear() methods:
     *  mock1.clear();
     *  mock2.clear();
     *
     *  //verification:
     *  verify(mock1).clear();
     *  verify(mock2).clear();
     *
     *  //verifyNoMoreInteractions() fails because get() methods were not accounted for.
     *  try { verifyNoMoreInteractions(mock1, mock2); } catch (NoInteractionsWanted e);
     *
     *  //However, if we ignore stubbed methods then we can verifyNoMoreInteractions()
     *  verifyNoMoreInteractions(ignoreStubs(mock1, mock2));
     *
     *  //Remember that ignoreStubs() *changes* the input mocks and returns them for convenience.
     * 
* Ignoring stubs can be used with verification in order: *

     *  List list = mock(List.class);
     *  when(mock.get(0)).thenReturn("foo");
     *
     *  list.add(0);
     *  System.out.println(list.get(0)); //we don't want to verify this
     *  list.clear();
     *
     *  InOrder inOrder = inOrder(ignoreStubs(list));
     *  inOrder.verify(list).add(0);
     *  inOrder.verify(list).clear();
     *  inOrder.verifyNoMoreInteractions();
     * 
* * @since 1.9.0 * @param mocks input mocks that will be changed * @return the same mocks that were passed in as parameters */ public static Object[] ignoreStubs(Object... mocks) { return MOCKITO_CORE.ignoreStubs(mocks); } /** * Allows verifying exact number of invocations. E.g: *

     *   verify(mock, times(2)).someMethod("some arg");
     * 
* * See examples in javadoc for {@link Mockito} class * * @param wantedNumberOfInvocations wanted number of invocations * * @return verification mode */ public static VerificationMode times(int wantedNumberOfInvocations) { return VerificationModeFactory.times(wantedNumberOfInvocations); } /** * Alias to times(0), see {@link Mockito#times(int)} *

* Verifies that interaction did not happen. E.g: *


     *   verify(mock, never()).someMethod();
     * 
* *

* If you want to verify there were NO interactions with the mock * check out {@link Mockito#verifyZeroInteractions(Object...)} * or {@link Mockito#verifyNoMoreInteractions(Object...)} *

* See examples in javadoc for {@link Mockito} class * * @return verification mode */ public static VerificationMode never() { return times(0); } /** * Allows at-least-once verification. E.g: *


     *   verify(mock, atLeastOnce()).someMethod("some arg");
     * 
* Alias to atLeast(1). *

* See examples in javadoc for {@link Mockito} class * * @return verification mode */ public static VerificationMode atLeastOnce() { return VerificationModeFactory.atLeastOnce(); } /** * Allows at-least-x verification. E.g: *


     *   verify(mock, atLeast(3)).someMethod("some arg");
     * 
* * See examples in javadoc for {@link Mockito} class * * @param minNumberOfInvocations minimum number of invocations * * @return verification mode */ public static VerificationMode atLeast(int minNumberOfInvocations) { return VerificationModeFactory.atLeast(minNumberOfInvocations); } /** * Allows at-most-x verification. E.g: *

     *   verify(mock, atMost(3)).someMethod("some arg");
     * 
* * See examples in javadoc for {@link Mockito} class * * @param maxNumberOfInvocations max number of invocations * * @return verification mode */ public static VerificationMode atMost(int maxNumberOfInvocations) { return VerificationModeFactory.atMost(maxNumberOfInvocations); } /** * Allows non-greedy verification in order. For example *

     *   inOrder.verify( mock, calls( 2 )).someMethod( "some arg" );
     * 
*
    *
  • will not fail if the method is called 3 times, unlike times( 2 )
  • *
  • will not mark the third invocation as verified, unlike atLeast( 2 )
  • *
* This verification mode can only be used with in order verification. * @param wantedNumberOfInvocations number of invocations to verify * @return verification mode */ public static VerificationMode calls( int wantedNumberOfInvocations ){ return VerificationModeFactory.calls( wantedNumberOfInvocations ); } /** * Allows checking if given method was the only one invoked. E.g: *

     *   verify(mock, only()).someMethod();
     *   //above is a shorthand for following 2 lines of code:
     *   verify(mock).someMethod();
     *   verifyNoMoreInvocations(mock);
     * 
* *

* See also {@link Mockito#verifyNoMoreInteractions(Object...)} *

* See examples in javadoc for {@link Mockito} class * * @return verification mode */ public static VerificationMode only() { return VerificationModeFactory.only(); } /** * Allows verifying with timeout. It causes a verify to wait for a specified period of time for a desired * interaction rather than fails immediately if has not already happened. May be useful for testing in concurrent * conditions. *

* This differs from {@link Mockito#after after()} in that after() will wait the full period, unless * the final test result is known early (e.g. if a never() fails), whereas timeout() will stop early as soon * as verification passes, producing different behaviour when used with times(2), for example, which can pass * and then later fail. In that case, timeout would pass as soon as times(2) passes, whereas after would run until * times(2) failed, and then fail. *

* It feels this feature should be used rarely - figure out a better way of testing your multi-threaded system *

* Not yet implemented to work with InOrder verification. *


     *   //passes when someMethod() is called within given time span
     *   verify(mock, timeout(100)).someMethod();
     *   //above is an alias to:
     *   verify(mock, timeout(100).times(1)).someMethod();
     *
     *   //passes as soon as someMethod() has been called 2 times before the given timeout
     *   verify(mock, timeout(100).times(2)).someMethod();
     *
     *   //equivalent: this also passes as soon as someMethod() has been called 2 times before the given timeout
     *   verify(mock, timeout(100).atLeast(2)).someMethod();
     *
     *   //verifies someMethod() within given time span using given verification mode
     *   //useful only if you have your own custom verification modes.
     *   verify(mock, new Timeout(100, yourOwnVerificationMode)).someMethod();
     * 
* * See examples in javadoc for {@link Mockito} class * * @param millis - time span in milliseconds * * @return verification mode */ public static VerificationWithTimeout timeout(long millis) { return new Timeout(millis, VerificationModeFactory.times(1)); } /** * Allows verifying over a given period. It causes a verify to wait for a specified period of time for a desired * interaction rather than failing immediately if has not already happened. May be useful for testing in concurrent * conditions. *

* This differs from {@link Mockito#timeout timeout()} in that after() will wait the full period, whereas timeout() * will stop early as soon as verification passes, producing different behaviour when used with times(2), for example, * which can pass and then later fail. In that case, timeout would pass as soon as times(2) passes, whereas after would * run the full time, which point it will fail, as times(2) has failed. *

* It feels this feature should be used rarely - figure out a better way of testing your multi-threaded system *

* Not yet implemented to work with InOrder verification. *


     *   //passes after 100ms, if someMethod() has only been called once at that time.
     *   verify(mock, after(100)).someMethod();
     *   //above is an alias to:
     *   verify(mock, after(100).times(1)).someMethod();
     *
     *   //passes if someMethod() is called *exactly* 2 times after the given timespan
     *   verify(mock, after(100).times(2)).someMethod();
     *
     *   //passes if someMethod() has not been called after the given timespan
     *   verify(mock, after(100).never()).someMethod();
     *
     *   //verifies someMethod() after a given time span using given verification mode
     *   //useful only if you have your own custom verification modes.
     *   verify(mock, new After(100, yourOwnVerificationMode)).someMethod();
     * 
* * See examples in javadoc for {@link Mockito} class * * @param millis - time span in milliseconds * * @return verification mode */ public static VerificationAfterDelay after(int millis) { return new After(millis, VerificationModeFactory.times(1)); } /** * First of all, in case of any trouble, I encourage you to read the Mockito FAQ: http://code.google.com/p/mockito/wiki/FAQ *

* In case of questions you may also post to mockito mailing list: http://groups.google.com/group/mockito *

* validateMockitoUsage() explicitly validates the framework state to detect invalid use of Mockito. * However, this feature is optional because Mockito validates the usage all the time... but there is a gotcha so read on. *

* Examples of incorrect use: *


     * //Oops, thenReturn() part is missing:
     * when(mock.get());
     *
     * //Oops, verified method call is inside verify() where it should be on the outside:
     * verify(mock.execute());
     *
     * //Oops, missing method to verify:
     * verify(mock);
     * 
* * Mockito throws exceptions if you misuse it so that you know if your tests are written correctly. * The gotcha is that Mockito does the validation next time you use the framework (e.g. next time you verify, stub, call mock etc.). * But even though the exception might be thrown in the next test, * the exception message contains a navigable stack trace element with location of the defect. * Hence you can click and find the place where Mockito was misused. *

* Sometimes though, you might want to validate the framework usage explicitly. * For example, one of the users wanted to put validateMockitoUsage() in his @After method * so that he knows immediately when he misused Mockito. * Without it, he would have known about it not sooner than next time he used the framework. * One more benefit of having validateMockitoUsage() in @After is that jUnit runner and rule will always fail in the test method with defect * whereas ordinary 'next-time' validation might fail the next test method. * But even though JUnit might report next test as red, don't worry about it * and just click at navigable stack trace element in the exception message to instantly locate the place where you misused mockito. *

* Both built-in runner: {@link MockitoJUnitRunner} and rule: {@link MockitoJUnitRule} do validateMockitoUsage() after each test method. *

* Bear in mind that usually you don't have to validateMockitoUsage() * and framework validation triggered on next-time basis should be just enough, * mainly because of enhanced exception message with clickable location of defect. * However, I would recommend validateMockitoUsage() if you already have sufficient test infrastructure * (like your own runner or base class for all tests) because adding a special action to @After has zero cost. *

* See examples in javadoc for {@link Mockito} class */ public static void validateMockitoUsage() { MOCKITO_CORE.validateMockitoUsage(); } /** * Allows mock creation with additional mock settings. *

* Don't use it too often. * Consider writing simple tests that use simple mocks. * Repeat after me: simple tests push simple, KISSy, readable & maintainable code. * If you cannot write a test in a simple way - refactor the code under test. *

* Examples of mock settings: *


     *   //Creates mock with different default answer & name
     *   Foo mock = mock(Foo.class, withSettings()
     *       .defaultAnswer(RETURNS_SMART_NULLS)
     *       .name("cool mockie"));
     *
     *   //Creates mock with different default answer, descriptive name and extra interfaces
     *   Foo mock = mock(Foo.class, withSettings()
     *       .defaultAnswer(RETURNS_SMART_NULLS)
     *       .name("cool mockie")
     *       .extraInterfaces(Bar.class));
     * 
* {@link MockSettings} has been introduced for two reasons. * Firstly, to make it easy to add another mock settings when the demand comes. * Secondly, to enable combining different mock settings without introducing zillions of overloaded mock() methods. *

* See javadoc for {@link MockSettings} to learn about possible mock settings. *

* * @return mock settings instance with defaults. */ public static MockSettings withSettings() { return new MockSettingsImpl().defaultAnswer(RETURNS_DEFAULTS); } /** * Helps debugging failing tests. Experimental - use at your own risk. We're not sure if this method will stay in public api. */ @Deprecated static MockitoDebugger debug() { return new MockitoDebuggerImpl(); } }