public class StaticVerifyTestClass {
	public Path doPathFileStuff(Path path) {
		try {
			return Files.createDirectories(path);
		} catch (IOException e) {
			throw new RuntimeException("It broke", e);
		}
	}
}

@PrepareForTest({ Files.class, StaticVerifyTestClass.class })
public class PowerMockitoStaticVerify {

	@Rule
	public PowerMockRule rule = new PowerMockRule();

        @Test
	public void createLogDumpDirectoriesFileExists() throws Exception {
		Path mockPath = mock(Path.class);
		mockStatic(Files.class);
		when(Files.createDirectories(eq(mockPath))).thenReturn(mockPath);

		new StaticVerifyTestClass().doPathFileStuff(mockPath);

		verifyStatic(Files.class);
		Files.createDirectories(eq(mockPath));
	}

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.thoughtworks.xstream.core.util.Fields (file:/C:/Users/david.birch/.gradle/caches/modules-2/files-2.1/com.thoughtworks.xstream/xstream/1.4.10/dfecae23647abc9d9fd0416629a4213a3882b101/xstream-1.4.10.jar) to field java.util.TreeMap.comparator
WARNING: Please consider reporting this to the maintainers of com.thoughtworks.xstream.core.util.Fields
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
Security framework of XStream not initialized, XStream is probably vulnerable.

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