I'm not sure what you mean "... check/compare values in the table and with the values the user keyed into the textboxes." But I guess you need to get the value from the textbox and write your sql like so:
String myKey = myTextBox.getText(); // something like this to get the value from the textbox
Statement stmt = con.createStatement();
// change the PERSONNAME with an appropriate column from your table INCIDENTDATA.
ResultSet rs = stmt.executeQuery("SELECT INCIDENTID FROM INCIDENTDATA WHERE PERSONNAME = '" + myKey + "'");
// And the rest is the same...
-- Arman