This week's book giveaway is in the Jython/Python forum.
We're giving away four copies of Murach's Python Programming and have Michael Urban and Joel Murach on-line!
See this thread for details.
Win a copy of Murach's Python Programming this week in the Jython/Python forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic

Sorting Collection of ArrayList  RSS feed

 
Deepak Kumar
Ranch Hand
Posts: 62
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi All,

How to sort a Collection of ArrayList based on the first(date)element of the ArrayList?

For example,(date is in YYYY/MM/DD format)
I have a Collection as: [[2002/02/01,12,34],[2005/02/08,45,67],[2001/02/11,78,91],[2006/01/27,78,34],[2006/01/28,88,45]]

where [2002/02/01,12,34],[2005/02/08,45,67],[2001/02/11,78,91][2006/01/27,78,34],[2006/01/28,88,45] are ArrayLists.

Now I want to sort the above collection on date by desc order as
[[2006/01/28,88,45],[2006/01/27,78,34],[2005/02/08,45,67],[2002/02/01,12,34],[2001/02/11,78,91]]

Please give me some clear idea on this?

Thanks& Regards,
Deepak
 
Jeremy Wilson
Ranch Hand
Posts: 166
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Wrap the arrays in their own object and implement the comparator interface. Then you can use Collections.sort to sort the array based on the method provided in the comparator implementation
 
Deepak Kumar
Ranch Hand
Posts: 62
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Thanks Jeremy Wilson
 
Rob Spoor
Sheriff
Posts: 20893
81
Chrome Eclipse IDE Java Windows
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Or use the Collections.sort method that takes a Comparator. That way you can keep using Strings.
 
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!