public Builder cacheFrom(String cacheFrom, String ...more) {
            if (more == null || more.length == 0) {
                return cacheFrom(Collections.singletonList(cacheFrom));
            }

            List<String> list = new ArrayList<>();
            list.add(cacheFrom);
            list.addAll(Arrays.asList(more));
            return cacheFrom(list);
        }
Use {@link #getAllAssemblyConfigurations()} unless you specifically want the configuration defined only by <code>assemblies</code>.
src/main/java/io/fabric8/maven/docker/config/BuildImageConfiguration.java