Java Web（9）struts 2 validation result设置

1. 使用action.validate后，如果有addFieldError后，struts会自动返回一个result为“input”，在官方的文档中是这样子的解释的Validation

Validation also depends on both the validation and workflow interceptors (both are included in the default interceptor stack). The validation interceptor does the validation itself and creates a list of field-specific errors. Theworkflow interceptor checks for the presence of validation errors: if any are found, it returns the "input" result (by default), taking the user back to the form which contained the validation errors.

2. 如果想设定另外一个resultName的话，可我们可以看一下struts是如何设定的，其中执行这一部分功能的拦截器是 DefaultWorkflowInterceptor 其中关键代码如下

protected String doIntercept(ActionInvocation invocation) throws Exception {
Object action = invocation.getAction();
if (action instanceof ValidationAware) {
ValidationAware validationAwareAction = (ValidationAware) action;
if (validationAwareAction.hasErrors()) {
if (LOG.isDebugEnabled()) {
LOG.debug("Errors on action " + validationAwareAction + ", returning result name 'input'");
}
String resultName = inputResultName;
//如何校验的当前action有实现这个类，
//则可以使用其接口的方法getInputResultName()来返回指定的resultName
if (action instanceof ValidationWorkflowAware) {
resultName = ((ValidationWorkflowAware) action).getInputResultName();
}
//使用注解来指定
InputConfig annotation = action.getClass().getMethod(invocation.getProxy().getMethod(), EMPTY_CLASS_ARRAY).getAnnotation(InputConfig.class);
if (annotation != null) {
if (!annotation.methodName().equals("")) {
Method method = action.getClass().getMethod(annotation.methodName());
resultName = (String) method.invoke(action);
} else {
resultName = annotation.resultName();
}
}
return resultName;
}
}
return invocation.invoke();
}