@Override
  public double getDouble(PropertyKey key) {
    checkArgument(key.getType() == PropertyKey.PropertyType.DOUBLE);
    return (double) get(key);
  }
@Test
  public void getDouble() {
    mConfiguration.set(PropertyKey.USER_CLIENT_CACHE_EVICTOR_LFU_LOGBASE, 1.1);
    assertEquals(1.1, mConfiguration.getDouble(PropertyKey.USER_CLIENT_CACHE_EVICTOR_LFU_LOGBASE),
        /*tolerance=*/0.0001);
  }