java - storing data from jtable into array -

i'm using jtable in application.i want store jtable data array.while i'm entering data table , when press delete button delete data in cell , click button store data array, shows error numberformatexception because of pressing delete button.how can solve this? code is

        int source = 0;         int temp = integer.max_value;         int dist = 0;         adjacencymatrix = new int[nodes][nodes];         (int row = 0; row < dtm.getrowcount(); row++) {             (int col = 1; col < dtm.getcolumncount(); col++) {                  if (dtm.getvalueat(row, col) == null || (dtm.getvalueat(row, col) == "") || (dtm.getvalueat(row, col) == " ")) {                     adjacencymatrix[row][col - 1] = integer.max_value;                 } else {                      adjacencymatrix[row][col - 1] = integer.parseint((string) dtm.getvalueat(row, col));                     // system.out.println("row ----" + row + "------" + (col - 1) + "------" + adjacencymatrix[row][col - 1]);                 }             }         }     } catch (exception ex) {         system.out.println(ex);         ex.printstacktrace();     } 

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