docs: @Requires("name != null")
    @Ensures({
      "result != null",
      "result == methodHandles.get(name)"
    })
    protected List<MethodContractHandle> internMethod(String name) {
      ArrayList<MethodContractHandle> handles = methodHandles.get(name);
      if (handles == null) {
        handles = new ArrayList<MethodContractHandle>();
        methodHandles.put(name, handles);
      }
      return handles;
    }