How to use stringReturningMethod method of org.mockitousage.MethodsImpl class

You are using mockito anyString() while calling the test method, it should be used only for verifying a mock object to ensure a certain method is called with any string parameter inside the test, but not to invoke the test itself. For your test use empty string "" instead to anyString().

You could refactor MyClass so that it uses dependency injection. Instead of having it create an AnythingPerformerClass instance you could pass in an instance of the class to the constructor of MyClass like so :

class MyClass {

   private final AnythingPerformerClass clazz;

   MyClass(AnythingPerformerClass clazz) {
      this.clazz = clazz;
   }

   public boolean performAnything() {         
     return clazz.doSomething();        
   }
}

You can then pass in the mock implementation in the unit test

@Test
public void testPerformAnything() throws Exception {
   AnythingPerformerClass mockedPerformer = Mockito.mock(AnythingPerformerClass.class);
   MyClass clazz = new MyClass(mockedPerformer);
   ...
}

Alternatively, if your AnythingPerformerClass contains state then you could pass a AnythingPerformerClassBuilder to the constructor.

Don't mock the InputStream. Instead, transform the String to an array of bytes using the getBytes() method. Then create a ByteArrayInputStream with the array as input, so that it returns the String when consumed, each byte at a time. Next, create a ServletInputStream that wraps a regular InputStream like the one from Spring:

public class DelegatingServletInputStream extends ServletInputStream {

    private final InputStream sourceStream;


    /**
     * Create a DelegatingServletInputStream for the given source stream.
     * @param sourceStream the source stream (never <code>null</code>)
     */
    public DelegatingServletInputStream(InputStream sourceStream) {
        Assert.notNull(sourceStream, "Source InputStream must not be null");
        this.sourceStream = sourceStream;
    }

    /**
     * Return the underlying source stream (never <code>null</code>).
     */
    public final InputStream getSourceStream() {
        return this.sourceStream;
    }


    public int read() throws IOException {
        return this.sourceStream.read();
    }

    public void close() throws IOException {
        super.close();
        this.sourceStream.close();
    }

}

and finally, the HttpServletRequest mock would return this DelegatingServletInputStream object.

The two syntaxes for stubbing are roughly equivalent. However, you can always use doReturn/when for stubbing; but there are cases where you can't use when/thenReturn. Stubbing void methods is one such. Others include use with Mockito spies, and stubbing the same method more than once.

One thing that when/thenReturn gives you, that doReturn/when doesn't, is type-checking of the value that you're returning, at compile time. However, I believe this is of almost no value - if you've got the type wrong, you'll find out as soon as you run your test.

I strongly recommend only using doReturn/when. There is no point in learning two syntaxes when one will do.

You may wish to refer to my answer at Forming Mockito "grammars" - a more detailed answer to a very closely related question.

My solution was to update my global ~/.gradle/gradle.properties file with the correct proxy settings:

org.gradle.daemon=true
systemProp.https.proxyHost=proxy.company.net
systemProp.https.proxyPort=8181
systemProp.http.proxyHost=proxy.company.net
systemProp.http.proxyPort=8181
systemProp.https.nonProxyHosts=*.company.com|localhost

this is in effect, the same as passing these as command line args to gradlew (./gradlew -Dhttp.proxyHost=xxx -Dhttp.proxyPort=xxx -Dhttps.proxyHost=xxx -Dhttps.proxyPort=xxx

One way is to use a Captor

ArgumentCaptor<List> captor = ArgumentCaptor.forClass(List.class);
verify(mock).createButtons(captor.capture());
assertEquals(x, captor.getValue().size()); // if expecting single list
assertEquals(x, captor.getValues().size()); // if expecting multiple lists

See #15 for the documentation.

You could also use a custom argument matcher. The documentation shows an example that does exactly what you want:

 class IsListOfTwoElements extends ArgumentMatcher<List> {
     public boolean matches(Object list) {
         return ((List) list).size() == 2;
     }
 }
 
 List mock = mock(List.class);
 when(mock.addAll(argThat(new IsListOfTwoElements()))).thenReturn(true);
 mock.addAll(Arrays.asList("one", "two"));
 verify(mock).addAll(argThat(new IsListOfTwoElements()));

You could, for instance, also add a constructor so you can specify list size desired, etc.

The code you posted works for me with the latest version of Mockito and Powermockito. Maybe you haven't prepared A? Try this:

A.java

public class A {
     private final String test;

    public A(String test) {
        this.test = test;
    }

    public String check() {
        return "checked " + this.test;
    }
}

MockA.java

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.equalTo;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest(A.class)
public class MockA {
    @Test
    public void test_not_mocked() throws Throwable {
        assertThat(new A("random string").check(), equalTo("checked random string"));
    }
    @Test
    public void test_mocked() throws Throwable {
         A a = mock(A.class); 
         when(a.check()).thenReturn("test");
         PowerMockito.whenNew(A.class).withArguments(Mockito.anyString()).thenReturn(a);
         assertThat(new A("random string").check(), equalTo("test"));
    }
}

Both tests should pass with mockito 1.9.0, powermockito 1.4.12 and junit 4.8.2

Use MockitoAnnotations.initMocks to initiate the @Mock and @InjectMocks objects. Your test would look something like:

@Mock
FastPowering fastPower;

@InjectMocks
Controller controller;

@Before
public void setup() {
    MockitoAnnotations.initMocks(this);
}

@Test
public void test() {
    ....
}

Since verifyNoMoreInteractions take an array of object we have to find a way to get all the created mocks.

You can create this class

public class MocksCollector {
    private final List<Object> createdMocks;

    public MocksCollector() {
        createdMocks = new LinkedList<Object>();
        final MockingProgress progress = new ThreadSafeMockingProgress();
        progress.setListener(new CollectCreatedMocks(createdMocks));
    }

    public Object[] getMocks() {
        return createdMocks.toArray();
    }
}

and then use it in your test :

    public class ATest {
    private final MocksCollector mocksCollector = new MocksCollector();

    @Test
    public void test() throws Exception {
        A a1 = mock(A.class);
        A a2 = mock(A.class);
        A a3 = mock(A.class);
        assertEquals("wrong amount of mocks", 3, mocksCollector.getMocks().length);
        verifyNoMoreInteractions(mocksCollector.getMocks());
        a3.doSomething();
        verifyNoMoreInteractions(mocksCollector.getMocks()); // fail
    }
}

or with annotations :

@RunWith(MockitoJUnitRunner.class)
public class A2Test {
    private final MocksCollector mocksCollector = new MocksCollector();

    @Mock
    private A a1;
    @Mock
    private A a2;
    @Mock
    private A a3;

    @Test
    public void test() throws Exception {
        assertEquals("wrong amount of mocks", 3, mocksCollector.getMocks().length);
        verifyNoMoreInteractions(mocksCollector.getMocks());
        a2.doSomething();
        verifyNoMoreInteractions(mocksCollector.getMocks()); // fail
    }
}

It works but it adds a dependency on mockito internal.