Set focus on particular cell in a JTable when using TableModel.

Question

I want to implement validation in my table cells. I the value does not satisfy certain condition then the focus should remain on the same cell and the user should be asked to enter valid value.
I am using TableModel and i have tried implementing validation in the setValueAt() method some thing like this.
setValueAt method of my table model.
public void setValueAt(Object value, int row, int col){
if(datalist.size()>row){
OutboundFieldMappingObj obj=(OutboundFieldMappingObj)datalist.get(row);
String str=null;
switch (col){
case 0:
str=Validator.getValidNumber((String)value,1,999999999L);
obj.setFiledName(str);
break;
case 1:
str=Validator.getValidString((String)value,128,false);
obj.setFiledClass(str);
break;
case 2:
obj.setSource((String)value);
break;
fireTableCellUpdated(row, col);
But this doesn't solve the issue. In this case after entering the value when i click on some other cell then it shows me a message stating that the value is invalid but it doesn't takes the focus back to same cell. The focus is shifted to the cell where i have clicked.
Please help me out in resolving the issue.
I have added the code of my validator class at the bottom if any one needs to have a look at it.
Thanks
Validator class
public class Validator {
public Validator() {
public static String getValidString(String val, int max, boolean upper) {
if (val == null || val.equals("")) {
showErrorMsg("The cell can not be left blank");
return " ";
if (val.length() > max) {
val = val.substring(0, max);
showErrorMsg("String value to long. Truncated to " + max +" characters.");
if (upper) {
val = val.toUpperCase();
return val;
public static String getValidNullableString(String val, int max, boolean upper) {
if (val == null) {
return null;
if (val.length() > max) {
val = val.substring(0, max);
showErrorMsg("String value to long. Truncated to " + max +" characters.");
if (upper) {
val = val.toUpperCase();
return val;
public static String getValidNumber(String number, int min, long max) {
try {
long num = Long.parseLong(number);
if (num < min) {
showErrorMsg("Number less than mininum value of " + min + ".");
return "" + min;
if (num > max) {
showErrorMsg("Number greater than maximum value of " + max +".");
return "" + max;
return number;
} catch (Exception x) {
showErrorMsg("Invalid Entry. Number Expected.");
return "0";
// return "";
public static boolean getValidNumber(String number) {
try {
Integer.parseInt(number);
return true;
} catch (Exception x) {
showErrorMsg("Invalid Entry. Number Expected.");
return false;
// return "";
public static void showErrorMsg(String message) {
JOptionPane.showMessageDialog(new java.awt.Frame(), message,
"Invalid Value!",
JOptionPane.ERROR_MESSAGE);
public static boolean validString(String str) {
if (str != null && str.length() > 0) {
return true;
return false;
}

Answer 1

You need to create a custom editor. Something like this:
http://forums.sun.com/thread.jspa?forumID=57&threadID=642364
If you need further help then you need to create a [Short, Self Contained, Compilable and Executable, Example Program (SSCCE)|http://homepage1.nifty.com/algafield/sscce.html], that demonstrates the incorrect behaviour.
Don't forget to use the Code Formatting Tags so the posted code retains its original formatting. That is done by selecting the code and then clicking on the "Code" button above the question input area.