Exception declaration for methods in a Controller

Question

Hi all enthusiasts of WD,
me again :-). I just noticed that one cannot declare exceptions thrown by a public method in a controller. Is it on purpose to shut down exception handling?
Maybe it makes sense to forbid this for the component interface controller, since the interface controller is accessible outside the component, it's not a good idea to ask other components to handle the exceptions specific to one component (after all, a component should be a self-contained unit); but for other controllers like component controller, it's convenient and safe to allow exception declaration --- it can only be accessed inside the component anyway.
Will this be supported in the future? Thanks.
Best regards,
Ge

Answer 1

Ge,
You misinterpreted my answer a bit.
1. Create own subclass of RuntimeException so you may distinguish your exceptions and standard ones like NullPointerException, ArrayIndexOutOfBoundsException:
public class GeRuntimeException extends RuntimeException {
  public GeRuntimeException(final String message) { super(message); }
  public GeRuntimeException(final Throwable cause) { super(cause); }
  public GeRuntimeException(final String message, final Throwable cause) { super(message, cause); }
2. Next create concrete sublcasses of your superclass:
public class GeSecurityException extends GeRuntimeException {
public class GeDatabaseException extends GeRuntimeException {
  public GeDatabaseException(final java.sql.Exception cause) { super(cause); }
3. Typical code pattern that throws your exception:
final PreparedStatement pstmt = ...;
try {
  pstmt.setInt(1, 0);
  pstmt.setString(2, "String param");
  pstmt.executeUpdate();
} catch (final SQLException ex) {
  throw new GeDatabaseException(ex);
4. Typical code pattern that handle exception:
try {
  wdThis.wdGetOtherController().makeDatabaseCall();
} catch (final GeDatabaseException ex) {
  wdComponentAPI.getMessageManager().reportException(
    new WDNonFatalException( ex.getCause() ), false
  return;
} catch (final GeRuntimeException ex) {
  wdComponentAPI.getMessageManager().reportError("Unexpected failure");
  return;
/* Some other code if no exception */
Notice that code above does not catch generic RuntimeException, only your sublcasses.
Valery Silaev
SaM Solutions
http://www.sam-solutions.net