Apples and Orangesby Daniel H. Steinberg
ONJava Newsletter for 01/09/2004
People have been thinking about units in Java for a long time. Instead of storing a particular length as 30, it would be nice to specify 30 inches, or, meters or miles. In "Apples and Oranges" Ori Kushnir looks at the Java units specification described in JSR 108, as well as various implementations. Some of the features include "Checking unit compatibility, Numeric value conversion, Scaling and other arithmetic operations on units, Implementation of standard units (e.g., units that are part of SI), and Unit parsers for standard specification formats."
In "Effective Use of Joins in SQL Statements", Satya Komatineni assumes that you know a thing or two about joins and need to think about the finer points. He provides 11 principles including suggestions on "how to use the join construct to solve practical issues in retrieving data from relational databases." Other principles "deal with the general question of patternizing a select statement."
In our java.net article this week we share the first in our "(Not so) Stupid Questions" series. This time you can join the discussion on where it is appropriate to declare methods to be static. There have been arguments on both sides. Agree or disagree with one, and feel free to contribute your opinion.
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From Macworld in San Francisco,
Daniel H Steinberg, editor
ONJava.com and java.net