public boolean execute(ActionContext actionCtx) throws Exception 
{
        // Is there a form bean for this request?
        ActionForm actionForm = actionCtx.getActionForm();
        if (actionForm == null) {
            return (false);
        }
        // Reset the form bean property values
        ActionConfig actionConfig = actionCtx.getActionConfig();
        reset(actionCtx, actionConfig, actionForm);
        populate(actionCtx, actionConfig, actionForm);
        handleCancel(actionCtx, actionConfig, actionForm);
        return (false);
}

Populate the form bean (if any) for this request.

 protected  void handleCancel(ActionContext context,
    ActionConfig actionConfig,
    ActionForm actionForm) throws Exception 
{
        Map paramValues = context.getParameterMap();
        // Set the cancellation attribute if appropriate
        if ((paramValues.get(Globals.CANCEL_PROPERTY) != null)
            || (paramValues.get(Globals.CANCEL_PROPERTY_X) != null)) {
            context.setCancelled(Boolean.TRUE);
        } else {
            context.setCancelled(Boolean.FALSE);
        }
}

Take into account whether the request includes any defined value for the global "cancel" parameter.

An issue was raised (but I don't think a Bugzilla ticket created) about the security implications of using a well-known cancel property which skips form validation, as you may not write your actions to deal with the cancellation case.

 abstract protected  void populate(ActionContext context,
    ActionConfig actionConfig,
    ActionForm actionForm) throws Exception
 Populate the given ActionForm with request parameter
values, taking into account any prefix/suffix values configured on the
given ActionConfig. 

 abstract protected  void reset(ActionContext context,
    ActionConfig actionConfig,
    ActionForm actionForm)
Call the reset() method on the specified form
bean.

 protected String trimParameterName(ActionConfig actionConfig,
    String name) 
{
        String stripped = name;
        String prefix = actionConfig.getPrefix();
        String suffix = actionConfig.getSuffix();
        if (prefix != null) {
            if (!stripped.startsWith(prefix)) {
                return null;
            }
            stripped = stripped.substring(prefix.length());
        }
        if (suffix != null) {
            if (!stripped.endsWith(suffix)) {
                return null;
            }
            stripped =
                stripped.substring(0, stripped.length() - suffix.length());
        }
        return stripped;
}

For a given request parameter name, trim off any prefix and/or suffix which are defined in actionConfig and return what remains. If either prefix or suffix is defined, then return null for name values which do not begin or end accordingly.