### Question:
DockerClient { public static boolean isDockerInstalled(Path dockerExecutable) { try { new ProcessBuilder(dockerExecutable.toString()).start(); return true; } catch (IOException ex) { return false; } } DockerClient(Path dockerExecutable, Map<String, String> dockerEnvironment); @VisibleForTesting  DockerClient(Function<List<String>, ProcessBuilder> processBuilderFactory); static boolean isDefaultDockerInstalled(); static boolean isDockerInstalled(Path dockerExecutable); String load(ImageTarball imageTarball, Consumer<Long> writtenByteCountListener); void save(
      ImageReference imageReference, Path outputPath, Consumer<Long> writtenByteCountListener); DockerImageDetails inspect(ImageReference imageReference); static final Path DEFAULT_DOCKER_CLIENT; }### Answer:
@Test public void testIsDockerInstalled_fail() { Assert.assertFalse(DockerClient.isDockerInstalled(Paths.get("path/to/nonexistent/file"))); }