Java Mysql Integrity Constraint Violation Exception

问题

My Swing applications throws few exceptions. I tried to catch Integrity Constraint Violation Exception and display message "Duplicate ID". But when that happened, without catching it here: catch(MySQLIntegrityConstraintViolationException ex) it goes to catch (SQLException ex). What I want to do is, catch Integrity Violation exception and display user friendly message instead of technical message comes from ex.getMessage(). How do I do this?

              ShippmentTransfer shipTrns = new ShippmentTransfer(shipID, GIN, issueDate, ToStore, itemName, Qty, Driver, Vehicle);
                    int res = ShipmentTansController.addShipGIN(shipTrns);
                    if (res > 0) {
                          JOptionPane.showMessageDialog(null, "Record Added");
                          resetAll();
                    }
              } catch (DataIntegrityViolationException ex) {
                    JOptionPane.showMessageDialog(null, "Duplicate ID");

              } catch (ClassNotFoundException ex) {
                    JOptionPane.showMessageDialog(null, ex.getMessage());
              } 
              catch (SQLException ex) {
                    JOptionPane.showMessageDialog(null, ex.gets);
              }
        }

回答1:

In order to catch specific SQLException, need to compare against SQl State using getSQLState() method. Ex: SQl State 23 for Data Integrity violation.

 catch (SQLException ex) {
                    if (ex.getSQLState().startsWith("23")) {
                          JOptionPane.showMessageDialog(null, "Duplicate");
                    } 
              }

Found from here

回答2:

you can not use

MySQLIntegrityConstraintViolationException  directly.

Because no exception available in java with that name.

try this

try {

}
catch (DataIntegrityViolationException ex) {
    .....
}

and then get the error code using ex.Then compare it

回答3:

For those checking later, you might either choose to check instance type as:

try {
...
} catch (Exception e) {

    if (e instanceof SQLIntegrityConstraintViolationException) {
          // duplicate record or alike problem
    }
}

来源：https://stackoverflow.com/questions/15894455/java-mysql-integrity-constraint-violation-exception