java - How to replace the value of '0' in a given pattern? -

i new in java, , trying replace value of "0's" "x" @ index "0,1,7,13,20,21,22, , 23" in below given sequence of 0 , 1's. , code far given. problem due can not obtain desired result.

001111
101110
100010
110000

public class task {     public static void main (string args[]) {         file file = new file("c:\\netbeansprojects\\task\\src\\file.txt");         bufferedreader reader = null;          try {             reader = new bufferedreader(new filereader(file));             string text = null;              //array lis declaration             arraylist<string> list = new arraylist<>();              while( (text = reader.readline()) != null){                 list.add(text);                 }             //printing array list.             system.out.println("print array list\n");             for(string d:list){                // system.out.println(d);             }             //convert arraylist 2darray             int nooflines = 0;             string[][] array = new string[list.size()][];             for(int i=0; < list.size(); i++){                 string row = list.get(i);                 nooflines++;                 array[i] = row.split("\0");             }              system.out.println("befor");             print(array);              int row=0,column=0;             for(int count=0; count<array.length; count++){                 if(row<nooflines-1 && array[row+1][column]=="0"){                     row++;                 }                 else                     if(column<array[row].length-1 && array[row][column+1]=="0"){                         column++;                     }                         array[row][column] = "x";             }        //     array[0][0] = "x";            system.out.println("after");            print(array);               //end try block         } catch (filenotfoundexception e) {             e.printstacktrace();         } catch (ioexception e) {             e.printstacktrace();         } //end catch block     } //end main       public static void print(string[][] array){          for(int i=0; i<array.length; i++){             for(int j=0; j<array[i].length; j++){                 system.out.print(array[i][j]);             }             system.out.println("");         }      } //end function print.  } //end class 

one problem in line:

array[i] = row.split("\0"); 

the backslash means row split @ character value zero, which not character occurs in text.

if meant split row @ "0", use row.split("0"). if meant split row characters, use row.split("").

then, using == compare strings. netbeans should warn not work, , suggest replace .equals (eg., array[row+1][column].equals("0"))