to.etc.domui.dom.errors
Class ErrorFenceHandler
java.lang.Object
to.etc.domui.dom.errors.ErrorFenceHandler
- All Implemented Interfaces:
- IErrorFence
- Direct Known Subclasses:
- PropagatingErrorFenceHandler
public class ErrorFenceHandler
- extends java.lang.Object
- implements IErrorFence
When controls or business logic encounters errors that need to be
reported back to the user they add an error to either a control (usually
for validation/conversion errors) or to the page itself (for errors where
there's no clear "location" where the problem has occured).
Making these errors visible is not the responsibility of a component, but
is delegated to one or more ErrorMessageListeners. These listeners get
called when an error is registered with a component (or when an error
is cleared).
The error listener is responsible for handling the actual reporting of the error,
and it usually does this by altering the output tree, for instance by adding
the error message to the page's defined "error box" and making that box visible. Other
listeners can change the CSS Class of the error node in question, causing it to be
displayed in a different color for instance.
If a page has no registered error handlers it "inherits" the default error handlers
from the current Application. By overriding that one you can easily alter the way
errors are reported in the entire application.
Special components that handle error messages also exist, and these components usually
register themselves as listeners when they are added to the tree. This is the best method
of handling error reporting because the page designer can easily determine where they are
shown.
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
ErrorFenceHandler
public ErrorFenceHandler(NodeContainer container)
getContainer
public NodeContainer getContainer()
addErrorListener
public void addErrorListener(IErrorMessageListener eml)
- Add a new error message listener to the page.
- Specified by:
addErrorListener
in interface IErrorFence
removeErrorListener
public void removeErrorListener(IErrorMessageListener eml)
- Discard an error message listener.
- Specified by:
removeErrorListener
in interface IErrorFence
- Parameters:
eml
-
addMessage
public void addMessage(NodeBase source,
UIMessage uim)
- Specified by:
addMessage
in interface IErrorFence
removeMessage
public void removeMessage(NodeBase source,
UIMessage uim)
- Specified by:
removeMessage
in interface IErrorFence
clearGlobalMessages
public void clearGlobalMessages(NodeBase source,
java.lang.String code)
- Specified by:
clearGlobalMessages
in interface IErrorFence