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CSV Import

Just want to caution you that I'm new to Java.

I've setup an object to import comma delimited data of type double. I
browsed the web to find pre-written code, and arrived at a solution that
imports each record as a HashMap type object, which is stored in an
ArrayList type object.

Based on what I read, it looked like the advantage to this method is that
the ArrayList object will expand automatically to accomodate the size of
the records to be imported.

Here's my question...I need to search through the ArrayList to find a
subset of records corresponding to a particualr group. What's the best way
to do this?

Thanks Chris
Aug 10 '06 #1
1 4881

"Christopher Smith" <ch***************@cablespeed.comwrote in message
news:vd****************************@40tude.net...
Just want to caution you that I'm new to Java.

I've setup an object to import comma delimited data of type double. I
browsed the web to find pre-written code, and arrived at a solution that
imports each record as a HashMap type object, which is stored in an
ArrayList type object.

Based on what I read, it looked like the advantage to this method is that
the ArrayList object will expand automatically to accomodate the size of
the records to be imported.

Here's my question...I need to search through the ArrayList to find a
subset of records corresponding to a particualr group. What's the best
way
to do this?
I don't understand how your comma delimited data would fit into a
HashMap... that said:

If you data isn't organized in any way (i.e. sorted in some order), then
there's not much you can do except iterate through each record, and check if
it matches your criteria.

Alternatively, you could read it all in, and then sort it in memory, and
then use the fact that it's sorted to somehow narrow in on your data
quickly. This would only be worthwhile if you repeated search through the
arraylist for many different subgroups of records.

- Oliver

Sep 5 '06 #2

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