This week's book giveaway is in the Big Data forum.
We're giving away four copies of Elasticsearch in Action and have Radu Gheorghe & Matthew Lee Hinman on-line!
See this thread for details.
The moose likes Java in General and the fly likes Need Help - Sorting an ArrayList of Strings Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login


Win a copy of Elasticsearch in Action this week in the Big Data forum!
JavaRanch » Java Forums » Java » Java in General
Bookmark "Need Help - Sorting an ArrayList of Strings" Watch "Need Help - Sorting an ArrayList of Strings" New topic
Author

Need Help - Sorting an ArrayList of Strings

K Bala
Greenhorn

Joined: Jul 14, 2005
Posts: 28
I have an ArrayList of Strings like this

"132 8"
"132 12"
"132 4"
"132 19"

When I sort it using Collections.sort() method, I get

132 12
132 19
132 4
132 8

I want the ArrayList to be sorted like this

132 4
132 8
132 12
132 19

How can I achieve this? Please help


Quitters never win; Winners NEVER QUIT!!!
Rob Spoor
Sheriff

Joined: Oct 27, 2005
Posts: 19908
    
  23

You'll need a custom comparator that, when comparing, splits the strings based on the space (hint: String.split), then converts the array elements to Integers (or Longs, depending on the length), and then compares these.

As for the comparing of the Integers, you'll need to compare the separate parts. Something like this:


SCJP 1.4 - SCJP 6 - SCWCD 5 - OCEEJBD 6
How To Ask Questions How To Answer Questions
 
rocket mass heater kickstarter
 
subject: Need Help - Sorting an ArrayList of Strings