Mockito and PowerMockito Error

Question

The following code works with PowerMockito version 1.7.3 and Mockito version 2.9.0

import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;

import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

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({FileUtils.class, Paths.class, Files.class})
public class FileUtilsTest {

    @Test
    public void testGetFileContents_Success() throws Exception {
        String filePath = "c:\\temp\\file.txt";

        Path mockPath = PowerMockito.mock(Path.class);
        PowerMockito.mockStatic(Paths.class);
        PowerMockito.mockStatic(Files.class);

        Mockito.when(Paths.get(Mockito.anyString())).thenReturn(mockPath);
        Mockito.when(Files.readAllBytes(Mockito.isA(Path.class))).thenReturn("hello".getBytes());

        String fileContents = FileUtils.getFileContents(filePath);
        assertNotNull(fileContents);
        assertTrue(fileContents.length() > 0);

        PowerMockito.verifyStatic(Paths.class);
        Paths.get(Mockito.anyString());
        PowerMockito.verifyStatic(Files.class);
        Files.readAllBytes(Mockito.isA(Path.class));
    }

}

However - when I go to the following versions - PowerMockito version 2.0.0-beta.5 and Mockito version 2.12.0 - I get the following error

    org.mockito.exceptions.base.MockitoException: 
Cannot mock/spy class java.nio.file.Paths
Mockito cannot mock/spy because :
 - final class

Any ideas what could be causing this issue or what I need to change?

Thank you Damien

Answer 1

I think you'll have to downgrade / postpone your upgrade to PowerMock v2.x.

See PowerMockito not compatible Mockito2 since their v2.0.55-beta release.

All PowerMock v2.x / Mockito v2.x integration work is covered by these two issues:

• PowerMock: https://github.com/powermock/powermock/issues/726
• Mockito: https://github.com/mockito/mockito/issues/1110

It looks like the goal is to have this working in the PowerMock v2.0.0 (and some Mockito 2.x version) but there's no clear statement of when that will be available.