An example of something I saw.

gistfile1.txt

  public class BaseServiceClass
  {
    
    protected static DictionaryType AllTheDataInTheWorld;
    
    public BaseServiceClass()
    {
      BaseServiceClass.AllTheDataInTheWorld = new DictionaryType();
    }
    
    protected void StoreData(Object literallyAnything)
    {
      BaseServiceClass.AllTheDataInTheWorld.add(literallyAnything);
    }

    public DictionaryType GetAllTheDataInTheWorld()
    {
      return BaseServiceClass.AllTheDataInTheWorld;
    }
    
  }
  
  public class Service extends BaseServiceClass
  {
    public Service(AnotherService dependency)
    {
      this.dependency = dependency;
      super();
    }

    public MyData DoSomethingINeedDone(OtherData usingThis)
    {
      
      // This method obtained by BaseServiceClass.
      this.StoreData(this.dependency.doSomethingElse(usingThis));
      
      return this;
      
    }
 
  }