code: public String execute() {
      String		result;
  
      initialize();
  
      result = check();
  
      if (result == null)
        result = determine();
  
      if (result == null) {
        m_Dependencies = new ArrayList<>();
        m_Dependencies.addAll(m_Classes);
        for (String cls: m_DependentClasses) {
          if (!m_Dependencies.contains(cls))
  	  m_Dependencies.add(cls);
        }
        for (String cls: m_Resources) {
          if (!m_Dependencies.contains(cls))
  	  m_Dependencies.add(cls);
        }
        Collections.sort(m_Dependencies);
      }
  
      return result;
    }
docs: Determines the dependencies.
  
  @return		null if successful, otherwise error message