Template Method Design
Hi, I have a requirement. Anybody has created an abstract action class that extends Action. It makes the perform method as final. And creates an abstract method satPerform that has to implemented by the classes extending thus providing sort of a base class. The intention behind is to take care of exception handling in the abstract class and rest in the child classes. Action perform() Abstract Class extends Action final perform(), abstract satPerform() SatAction extends Abstract - satPerform(). The pattern is Template Method Design. If anybody has used such approach, please share the details. If somebody could shed some light in this topic i would be grateful. Vijay K. Hegde Software Engineer Infosys Technologies Limited, Hyderabad * (040) 2300 5222 extn 23239 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Template Method Design
Take a look at Chapter 10 - Exception Handling in Programming Jakarta Struts by chuck cavaness.. i think you'll find this very helpful. I've implement this with Action but ill soon need to do the same for Dispatch Action too... has anyone done likewise for Dispatch and other such actions? From: Vijay K Hegde [EMAIL PROTECTED] Reply-To: Struts Users Mailing List [EMAIL PROTECTED] To: Struts Users Mailing List [EMAIL PROTECTED] Subject: Template Method Design Date: Thu, 18 Sep 2003 15:01:59 +0530 Hi, I have a requirement. Anybody has created an abstract action class that extends Action. It makes the perform method as final. And creates an abstract method satPerform that has to implemented by the classes extending thus providing sort of a base class. The intention behind is to take care of exception handling in the abstract class and rest in the child classes. Action perform() Abstract Class extends Action final perform(), abstract satPerform() SatAction extends Abstract - satPerform(). The pattern is Template Method Design. If anybody has used such approach, please share the details. If somebody could shed some light in this topic i would be grateful. Vijay K. Hegde Software Engineer Infosys Technologies Limited, Hyderabad * (040) 2300 5222 extn 23239 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] _ Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Template Method Design
I use the technique of finalising execute (1.1 equivelent of perform) and having it do the lions share of the work for things. For example in a crud action most of the work is occuring in execute and the subclasses just do those things that are specific to the record type in question... I find it works *very* well, and indeed I would suggest that for all but the most trivial apps your wasting a lot of your own time by having any concrete action class do ALL the work when you could be using inheritance and an abstract superclass 'template' to take care of the generic stuff. (Incidentally one thing Ive found useful when doing things this way is to have the superclass execute method create an 'ActionContext' bean that encapsulates the four parameters that get passed to execute, and then you pass that to your subclasses. Saves a lot of time, and gives you a spot you can add extra stuff to later instead of having to change lots of method signatures.) In terms of exception handling though, you may be better off using the struts ExceptionHandler feature for dealing with exceptions thrown by actions. -Original Message- From: Vijay K Hegde [mailto:[EMAIL PROTECTED] Sent: Thursday, 18 September 2003 17:32 To: Struts Users Mailing List Subject: Template Method Design Hi, I have a requirement. Anybody has created an abstract action class that extends Action. It makes the perform method as final. And creates an abstract method satPerform that has to implemented by the classes extending thus providing sort of a base class. The intention behind is to take care of exception handling in the abstract class and rest in the child classes. Action perform() Abstract Class extends Action final perform(), abstract satPerform() SatAction extends Abstract - satPerform(). The pattern is Template Method Design. If anybody has used such approach, please share the details. If somebody could shed some light in this topic i would be grateful. Vijay K. Hegde Software Engineer Infosys Technologies Limited, Hyderabad * (040) 2300 5222 extn 23239 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
