WebSphere Application Server Best Practices
1 WebSphere Application Server Best Practices – Overview
这个文档描述了在开发基于servlets、JSP、JDBC、EJB等技术的WEB Application的过程中的最佳实践。下表列出了这些最佳时间，并以从1到5的等级来标识这些实践对性能的影响程度和发生的频率等。
Category
Best Practice Number and Description
Importance
Servlets
1. Do not store large object graphs in HttpSession
2
Servlets
2. Release HttpSessions when finished
3
JSP Files
3. Do not create HttpSessions in JSPs by default
4
Servlets
4. Minimize synchronization in Servlets
2
Servlets
5. Do not use SingleThreadModel
5
All web and enterprise application components
6. Use JDBC connection pooling
3
All web and enterprise application components
7. Reuse datasources for JDBC connections
1
All web and enterprise application components
8. Release JDBC resources when done
3
Servlets
9. Use the HttpServlet Init method to perform expensive
operations that need only be done once
4
All web and enterprise application components
10. Minimize use of System.out.println
2
All web and enterprise application components
11. Avoid String concatenation “+=”
1
Enterprise beans
12. Access entity beans from session beans
3
Enterprise beans
13. Reuse EJB homes
1
Enterprise beans
14. Use “Read-Only” methods where appropriate
3
Enterprise beans
15. Reduce the transaction isolation level where appropriate
5
Enterprise beans
16. EJBs and Servlets - same JVM - “No local copies”
2
Enterprise beans
17. Remove stateful session beans when finished
2
Servlets
18. Don’t use Beans.instantiate() to create new bean
instances
3
对于每个实践，本文档提供了以下的内容：
1、描述和简要的背景介绍。
2、一段需要避免的代码片断。
3、一段最佳时间的实例代码片断。
4、通过列举最佳实践的益处来对其性能作比较。
对于开发者而言，要想开发出高性能的WEB Application的话除了上面列出的最佳实践之外还要掌握良好的Java语言构建技巧，在Bibliography – Additional References 部分可以到找到相应的参考。