code: @Nullable
    public static <T> T getFirstSPIImplementation (@Nonnull final Class <T> aSPIClass)
    {
      return getFirstSPIImplementation (aSPIClass, ClassLoaderHelper.getDefaultClassLoader (), null);
    }
docs: Uses the {@link ServiceLoader} to load all SPI implementations of the
  passed class and return only the first instance.
  
  @param <T>
  The implementation type to be loaded
  @param aSPIClass
  The SPI interface class. May not be <code>null</code>.
  @return A collection of all currently available plugins. Never
  <code>null</code>.