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Arrays with files

prerna boja
Ranch Hand

Joined: Aug 19, 2004
Posts: 67
Hi all,

I have a program to display the array data n find the largest n smallest values.

I am getting an exception in the main program as java.lang.NumberFormatException :For input String :"2 3 4".

Please tell me where I am wrong. I feel my getTable method is the problem.
Please help me out it is really tough I always get stuck at using indexOf n substring.

debug.dat :
4 4
1 2 3 4
5 6 7 8
9 8 7 6
1 3 3 5

Aly Gilani

Joined: Jul 20, 2004
Posts: 7
Hi Prerna,

Instead of using substring you can try using:

String [] strArray = line.split(" ");

and then just loop through the values in the row.

Hope that helps,

D Burks

Joined: Jul 14, 2012
Posts: 1
Having your constructor take the dimensions of your array requires you to know what is inside your file. However, since the program is going to open the file and read these dimensions anyway, just let the program figure it out. All you need to know then is the filepath to the file and your program will do the rest. Thus I modified the code to take advantage of this. Also, as Aly had said using the split method from the String class is much simpler.

Then you can call your printTable(), smallest() and largest() methods. Here's how I called it :

and the output:

The first four lines are from the println() on line 28. I was using that to debug and forgot to remove it. That should be removed
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46367
Welcome to the Ranch D Burks
I agree. Here's the link:
subject: Arrays with files
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