Java service classes...I have two service classes one for 'store'(save) data, another service for 'load' to display content.It was implemented , now new requirement - depends on user input for load (for ex version) if it is not latest one do some logic to upgrade(based on some xslt transfomation) and save(store) the content. In this scenario for upgrade ,'save' logic is same as in actual 'store' service. I should reuse the code for 'save' which is for load service also. One restriction is shouldn't call storeservice from load service.I need to put common logic/code in some helper/util class?. Is it good design creating a helper/util class ??.In that case almost 90% code for store service need to move into util/helper class!!!!any other thought for the solution 
Design pattern for java service class
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