- 學位論文
以輕量級框架為基礎簡化傳統分散式元件複雜度之研究
In The Way of Simplify Development for Java Object Using POJO
摘要
分散式元件（Enterprise JavaBean，EJB）是一種以分散式物件為基礎的軟體元件，透過開發EJB可以簡化以Java建立企業級分散式元件應用系統的開發過程，讓開發人員專心於商業邏輯部分，而元件本身已俱備結合分散式計算、企業邏輯封裝、資料庫存取、交易處理等機制，因為功能面講求強大、穏定，開發時的複雜度也就提高，就現階段而言，開發EJB所面臨的問題包括：（1）必需寫很多的Classes及Interfaces，（2）複雜且多的XML定義檔，（3）與EJB Container過度結合導致測試不易，（4）Entities效能不好與EJBQL語法複雜。 輕量級框架（Plain Old Java Object，POJO）的本質，是希望讓開發人員容易進行程式撰寫、功能測試、維護及需求變更等工作，使整個開發流程趨於簡單快速，避免因為技術複雜度過高，引發太多的不確定風險，進而有效提高生產力。EJB3是以POJO為核心設計的輕量級框架，主要是為了改善傳統分散式架構下開發EJB時的複雜性。 本研究主要目的是希望應用目前新的資訊技術輕量級框架「EJB3」，藉由輕量級框架的特性簡化傳統分散式元件開發時的複雜度，建置分散式元件應用系統，並探討驗證以輕量級框架來改善元件開發複雜度的效益與可行性。
並列摘要
Distributed Component is a software object based on EJB（Enterprise JavaBean、EJB. By developing Distributed Component on EJB can simplify the EJB system developing process built on Java, and allow developers to concentrate on business logic. The object itself has several mechanisms such as distributed computing、enterprise logic packaging、database storage, transaction, etc. Because EJB requires powerful and stable functions, the complexity of development increases as well. Currently, problems of developing EJB systems include: (1) requiring huge amounts of classes and interfaces, (2) need a lot of complex XML definition files, (3) EJB and Container are over integrated and cause great difficulty on testing, (4) inefficient Entities and complicated EJBQL language. The essence of Plain Old Jave Object (POJO) is that developers can easily write, test, maintain and change program, therefore the developing process will be fast and easy. POJO can also avoid excess risks arisen from complicated techniques, therefore increase productivity. The EJB3 uses POJO as its core design mainly to improve the complexity of developing EJB by using old distributed architecture. The purpose of this research is to apply the latest EJB3 to build EJB system and to simplify the complexity of developing process using old EJB. This research also studies the validity and benefit of using POJO to improve the productivity of developing process.