Strategy pattern and the Servlet API

[Dan Drillich]

Good Day,

The book "Sun Certified Enterprise Architect for J2EE, Study Guide" by Paul Allen and Joseph Bambara says the following on page #268:

Applicable Scenarios (for the Strategy pattern)

- Multiple classes differ only in their behaviors. The servlet API is a classic example of this.

I think the pattern is used in the init() and service() methods.
init() gets as a parameter an instance that implements the ServletConfig interface and service() gets instances which implement the ServletRequest and ServletResponse interfaces.

Any thoughts?

Thanks,
Dan

[Ramon Gill]

I think you're right Dan. All servlets extend the same httpservlet, but have their own strategy for methods init/service/doget/dopost). This seems like a good explanation of 'strategy' to me.

Ray

[James Clinton]

Ramon

I not sure I quite agree with you that doGet() and doPost() are part of the statergy pattern, because they're not part of the Servlet interface.

Where as init() and service() are.

Or have I miss-understood the pattern which is all about programming to Interfaces?

James

[James Clinton]

A link to JavaWorld with a good example using this pattern for interested Ranchers.

Strategy for Success