public Sdk getSdk(int apiLevel) {
    Sdk sdk = knownSdks.get(apiLevel);
    return sdk == null ? new UnknownSdk(apiLevel) : sdk;
  }
@Test
  public void shouldCacheSdks() throws Exception {
    assertThat(sdkCollection.getSdk(1234)).isSameInstanceAs(fakeSdk1234);
    assertThat(sdkCollection.getSdk(1234)).isSameInstanceAs(fakeSdk1234);

    verify(mockSdkProvider, times(1)).getSdks();
  }