structs2与ajax结合，无论采用$.post还是$.ajax都捕获不到服务器产生的错误，这是structs2内部设计的不是很好,
但是$.ajax捕获错误在servlet能做到。因为
public void serviceAction(HttpServletRequest request,HttpServletResponse response,ServletContext context,
ActionMapping mapping) throws ServletException {
Map<String,Object> extraContext = createContextMap(request,response,mapping,context);
// If there was a prevIoUs value stack,then create a new copy and pass it in to be used by the new Action
ValueStack stack = (ValueStack) request.getAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY);
boolean nullStack = stack == null;
if (nullStack) {
ActionContext ctx = ActionContext.getContext();
if (ctx != null) {
stack = ctx.getValueStack();
}
}
if (stack != null) {
extraContext.put(ActionContext.VALUE_STACK,valueStackFactory.createValueStack(stack));
}
String timerKey = "Handling request from Dispatcher";
try {
UtilTimerStack.push(timerKey);
String namespace = mapping.getNamespace();
String name = mapping.getName();
String method = mapping.getMethod();
Configuration config = configurationManager.getConfiguration();
ActionProxy proxy = config.getContainer().getInstance(ActionProxyFactory.class).createActionProxy(
namespace,name,method,extraContext,true,false);
request.setAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY,proxy.getInvocation().getStack());
// if the ActionMapping says to go straight to a result,do it!
if (mapping.getResult() != null) {
Result result = mapping.getResult();
result.execute(proxy.getInvocation());
} else {
proxy.execute();
}
// If there was a prevIoUs value stack then set it back onto the request
if (!nullStack) {
request.setAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY,stack);
}
} catch (ConfigurationException e) {
// WW-2874 Only log error if in devMode
if(devMode) {
String reqStr = request.getRequestURI();
if (request.getQueryString() != null) {
reqStr = reqStr + "?" + request.getQueryString();
}
LOG.error("Could not find action or result\n" + reqStr,e);
}
else {
if (LOG.isWarnEnabled()) {
LOG.warn("Could not find action or result",e);
}
}
sendError(request,context,HttpServletResponse.SC_NOT_FOUND,e);//产生错误的模板页面，并返回到客户端
} catch (Exception e) {
sendError(request,HttpServletResponse.SC_INTERNAL_SERVER_ERROR,e);//产生错误的模板页面，并返回到客户端
} finally {
UtilTimerStack.pop(timerKey);
}
}
