Java，

Java，

Action在采用PrintWriter向前端返回内容的时候，出现如下异常：
[color=red]java.lang.IllegalStateException: getWriter() has already been called for this response
java.lang.IllegalStateException:getOutputStream() has already been called for this response[/color]
经检查，Action中的方法既有返回值又有PrintWriter输出，将方法返回值改为void就好了。