code: public <S, T> Converter<S, T> findConverter(Class<S> source, Class<T> target, Class<? extends Annotation> qualifier) {
  		return findConverter(new ConverterKey<S,T>(source, target, qualifier == null ? DefaultBinding.class : qualifier));
  	}
docs: Resolve a Converter with the given input and output classes. Instances of the input class can be converted into
  instances of the output class
  @param source The source class
  @param target The target class
  @param qualifier The qualifier for which the marshaller must be registered