RFE: Performance of JComboBox with DefaultComboBoxModel (re-open 4138101?)

Name: yyT116575 Date: 10/25/2000


orig synopsis: "Horrible performance of JComboBox with DefaultComboBoxModel"
see also # 4173836

java version "1.2.2"
Solaris VM (build Solaris_JDK_1.2.2_05a, native threads, sunwjit)


I'm sorry to resubmit a bug which is already in your database, but
I seriously think you should look at this one again. It would take a
sun developer all of five minutes to fix, and it would improve performance
of JComboBox by SECONDS not just milliseconds.

Considering the bang for the buck, I simply can't believe this has gone
so long without being fixed.

Please reexamine bug 4138101. The problem is that with a
DefaultComboBoxModel, there's no way to add a large group of items to
the model. If you add them one at a time, with addElement(Object val),
then fireIntervalAdded() is called for each and every element you add,
which is VERY VERY slow.

I had a frame that contained a table. Two of the columns in the table
had cell editors that were JComboBoxes, each with about 100 items in them.
Initially, I added the items to the JComboBoxes one at a time. It took
my frame a whopping 15 - 17 seconds to come up!!!! Almost unbelievable.
Then I simply changed the constructors of the JComboBoxes to take a vector
of the values, and the frame came up in about 3 seconds.

The problem I face is in a different part of the code where I MUST change the
list of values in the combo box after the combo box is constructed. I
simply can't do it in a quick way.

PLEASE FIX THIS! It's SOOOO easy to fix on your end and will improve
performance for lots and lots of your users.
(Review ID: 110650)
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