Monday May 29, 2006
Refactoring with Jackpot in Glassfish
Jackpot is a Java
source code reengineering tool from NetBeans. Intrigued by all
the buzz around it in JavaOne, I decided to try Jackpot beta on Glassfish. By
following the short
instruction and was able to get it up and running in my NetBeans
5.0 in a few minutes. It comes with 14 built-in rules, grouped
into 2 rule sets: default and Effective Java:
I first tried to let Jackpot query several modules in Glassfish at
once, including appserv-commons, appserv-core, appserv-webtier,
appserv-http-engines, etc, which turned out to be too ambitious in my
machine. I had several OutOfMemoryError. Then I tried only
appserv-core module with only one query -- unnecessary cast. The
query completed in less than 1 minute, and found 65 matching
nodes. I randomly checked a few and these casts are really
unnecessary casts. Double-click on one item will open up two
side-by-side diff windows, showing the suggested fix. If I click
Do Refactoring button, all these 65 unnecessary casts will be fixed
automatically. IMO, they are pretty low-risk fixes and will not
only clean up code, but also boost the server performance.
If I'm assigned the task of fixing them, I wouldn't do as well as
Jackpot does. I will need much more time than one-click, and I'm
sure I will mess something up along the way. Jackpot strikes me
as a dangerous tool, cause it can put us out of job.
Fixing some types of anti-patterns needs human intervention, for
instance, bad-finally-blocks anti-pattern. There are no suggested
fix for these types of query results. Jackpot found 15 such
issues in appserv-core module, some of them are actually false alarm,
for instance, it interprets the return statement inside anonymous
inner-class as a bad return statement that will be executed inside the
finally block:
} finally {
java.security.AccessController.doPrivileged(
new
java.security.PrivilegedAction() {
public java.lang.Object run() {
// do something
return null;
}
});
}
There are still some rough edges, given that it's still at beta.
I'd like to see a better query result console, adding buttons like
sort, filter, select all, deselect all on all matching items.
Since there may be hundreds of matching nodes for one query, as I've
seen in Glassfish, I hate to select/deselect them one by one, or
customize rules.
PS: I entered a bug for the above issue in NetBeans | Jackpot
[Issue 77082] New - return statement in anonymous innerclass reported as bad finally block
Posted at 06:07PM May 29, 2006 by chengfang in Glassfish | Comments[0]
