This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
Sege Stephen wrote: I reckon I need to use a nexted for loop, but I am not getting the desired result.
your guess is right! by the way : what problem you are facing?
Sege Stephen wrote: how do I convert to it Object  data
do you mean converting List of List into Array of Arrays? you need to loop the outer List and the convert to Array and add this array element into another array. hence Array of Arrays. If you only need insertion of List element/List, then this operation/looping is unnecessary.
Sege Stephen wrote:Following the response that I should make it an Array of object,
i changed my code to
I think you're missing the point. Right now, you have the contained Lists holding data that almost definitely should be held in Objects representing whatever that data is. Say I had a List of animals, each with a name, an age, and a sound they make. Your way would be doing something like:
Then, to access a particular attribute, you'd have to remember which index of the contained list represented that data. That's not the way to do it. Instead, create another class that contains the data. We say create a List of Objects because every class you write will extend Object. We don't mean literally use references to instances of Objects. So my example would be:
Now, to get a particular attibute, you would call the getter function of whatever data you're looking for. Or, you could put it all in a toString() method as mentioned above. That just depends on your requirements.