Why is it not running

Question

According to my knowledge i did everything right,yet it is not running.import javax.swing.JOptionPane;
import java.io.*;
public class file1 {
static int[][] number=new int[1000][1000];
static int row,column;
    public static void main(String[] args) {
   readFile();
   /*for(int i=0;i<row;i++)
        for(int j=0;j<column;j++)
             System.out.println(number[i][j]);
     String result="";
     for(int i=0;i<row;i++)
          result+="Row "+(i+1)+" Minimum value: "+findMinimum(i)+"\n";
     JOptionPane.showMessageDialog(null, result);
     JOptionPane.showMessageDialog(null, "Even numbers in array are: "+displayEven());
     JOptionPane.showMessageDialog(null, "Sum of all number is: "+getSum());
     //prints the box with dialogue minimum vale, even numbers in array
     //and sum of all number is: 
for(int i=0;i<row;i++)
     sortRow(i);
JOptionPane.showMessageDialog(null, "After sorting each row:\n"+Print());
    // prints the box with dialogue after sorting each row
private static void readFile(){
     String ver,hor,temp;
     String[] copy= new String[1000];
     int i=0,j,len=1,beg=0,end=0;
     try{
     FileReader fr = new FileReader("test.txt");
     BufferedReader br = new BufferedReader(fr);
     if(copy[0]==null) System.out.println();
          while((copy[i++] = br.readLine()) != null);
               fr.close();          
               i--;     
     }catch(IOException e){}
     if(copy[0]==null) System.out.println();
          while(copy[0].charAt(end)!=',');
               end++;
          ver=copy[0].substring(beg,end);
          row=Integer.parseInt(ver);
          beg=end;
          while(end<copy[0].length())
               end++;
          hor=copy[0].substring(beg+1,end);
          column=Integer.parseInt(hor);
          i=0; j=0;     
          while(i<row){
               end=0;beg=0;j=0;
               while(end<copy[i+1].length())
                    try{
                              while(copy[i+1].charAt(end)!=','  &&  end<copy[i+1].length())
                                   end++;
                              }catch(StringIndexOutOfBoundsException e){}
                         temp=copy[i+1].substring(beg,end);
                         number[i][j]=Integer.parseInt(temp);
                         System.out.println(number[i][j]);
                         beg=++end;
                         j++;
                    //JOptionPane.showMessageDialog(null,"The sum is"+integers,"Samir",JOptionPane.WARNING_MESSAGE);     
               i++;
private static int findMinimum(int row)
int min=0,max=0;
for(int i=0;i<column;i++)
if(number[row][i]>max)
max=number[row][i];
min=max;
for(int i=0;i<column;i++)
if(number[row][i]<min)
min=number[row][i];
return min;
private static String displayEven()
String result="";
for(int i=0;i<row;i++)
for(int j=0;j<column;j++)
if(number[i][j]%2==0)
result+=number[i][j]+" ";
return result;
private static int getSum()
int result=0;
for(int i=0;i<row;i++)
for(int j=0;j<column;j++)
result+=number[i][j];
return result;
private static void sortRow(int inrow)
int tempo;
for(int j=0;j<column;j++)
for(int i=1;i<column;i++)
if(number[inrow][i]<number[inrow][i-1])
tempo=number[inrow][i];
number[inrow][i]=number[inrow][i-1];
number[inrow][i-1]=tempo;
private static String Print()
String result="";
for(int i=0;i<row;i++){
for(int j=0;j<column;j++)
result+=number[i][j]+" ";
     result+="\n";
return result;

Answer 1

i did not go thro the full code.. but line 56 is the while condition.
if(copy[0]==null) System.out.println();
while(copy[0].charAt(end)!=',');
               end++;you are doing a sys out if copy[0] is null.. but the while condition says copy[0].xxx()! if copy[0] (whatever it may be) is null, you will get a new line printed and after that it will thro NPE.. may be there is an else clause?? just wondering what could be the reason behind such a code flow.. if (null) sys out; null.doStuff(); what else do you expect to happen if the IF condition succeeds?