All posts by ajohnson

Java accessor visibility

Java accessor visibility: When to make accessors public, and when to keep them private

“So how do you determine the proper visibility of an accessor method? My experience is that you should always strive to make accessors protected, so only subclasses can access the attributes. You should try to make accessors private if subclasses don’t need access to the attribute. Only when an external class or object needs to access an attribute should you make the appropriate getter or setter public. It is quite common for the visibility of corresponding getter and setter methods to be different: in the class Seminar, you see the getTitle() method has public visibility, yet setTitle() has private visibility.”

Wafer

Wafer is a research project which compares the many open source web application frameworks which are available using a common example application. This research project is designed to compare the application frameworks on a level field by specifying an example application so that the application features become irrelevent and the merits of each framework becomes the focus.

Instant Messaging in Java

I got way too many books for Christmas which leads to perpetual grazing: reading 10 pages of that book and 15 of that one and ultimately nowhere because you can’t concentrate on a single topic.

So a couple days ago I was reading Instant Messaging in Java, a book about Jabber. I read the introduction and the first couple chapters and was surprised to find out that Jabber isn’t really about jabberd (the compiled server written in C) but is much broader: “Jabber is an open XML protocol for the real-time exchange of messages and presence between any two points on the Internet.”[source] So Jabber is NOT a product you buy (although you can products), nor is it software (although you can download it in various forms). It’s a protocol, no different than HTTP. Anyone can write an HTTP server in any language and anyone can write a Jabber server in any language, as long as it abides by the spec.