### Question:
CachedCurrentInstallationController implements ParseCurrentInstallationController { @Override public void clearFromMemory() { synchronized (mutex) { currentInstallation = null; } } CachedCurrentInstallationController(
      ParseObjectStore<ParseInstallation> store, InstallationId installationId); @Override Task<Void> setAsync(final ParseInstallation installation); @Override Task<ParseInstallation> getAsync(); @Override Task<Boolean> existsAsync(); @Override void clearFromMemory(); @Override void clearFromDisk(); @Override boolean isCurrent(ParseInstallation installation);  }### Answer:
@Test public void testClearFromMemory() throws Exception { CachedCurrentInstallationController controller = new CachedCurrentInstallationController(null, null); controller.currentInstallation = mock(ParseInstallation.class); controller.clearFromMemory(); assertNull(controller.currentInstallation); }