CannotMockFinalClass
Mockito cannot mock final classes

Severity
WARNING
Has Fix?
NO_FIX

The problem

Mockito cannot mock final classes. See https://github.com/mockito/mockito/wiki/FAQ for details.

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("CannotMockFinalClass") to the enclosing element.


Positive examples

CannotMockFinalClassPositiveCases.java

/*
* Copyright 2014 The Error Prone Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/


import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import org.mockito.Mock;
import org.mockito.Mockito;

/** Test for CannotMockFinalClass. */
@RunWith(JUnit4.class)
public class CannotMockFinalClassPositiveCases {
static final class FinalClass {}

// BUG: Diagnostic contains: Mockito cannot mock
@Mock FinalClass impossible;

public void method() {
// BUG: Diagnostic contains: Mockito cannot mock
FinalClass local = Mockito.mock(FinalClass.class);
}
}

Negative examples

CannotMockFinalClassNegativeCases.java

/*
* Copyright 2014 The Error Prone Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/


import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import org.mockito.Mock;
import org.mockito.Mockito;

/** Test for CannotMockFinalClass. */
@RunWith(JUnit4.class)
public class CannotMockFinalClassNegativeCases {
static class NonFinalClass {}

@Mock NonFinalClass okToMock;

public void method() {
NonFinalClass local = Mockito.mock(NonFinalClass.class);
}
}

CannotMockFinalClassNegativeCases2.java

/*
* Copyright 2014 The Error Prone Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/


import org.mockito.Mock;
import org.mockito.Mockito;

/** Test for CannotMockFinalClass in the absence of @RunWith(JUnit4.class). */
public class CannotMockFinalClassNegativeCases2 {
static final class FinalClass {}

@Mock FinalClass impossible;

public void method() {
FinalClass local = Mockito.mock(FinalClass.class);
}
}