public ModelAndView FilecardAdd(HttpServletRequest request,Filecard filecard){
Integer id=new Integer(request.getParameter("id"));
if(id==null){
id=UUID.randomUUID().toString();
}
filecard.setId(id);
fs.addFilecard(filecard);
mv.setViewName("redirect:getFilecard.do");
return mv;
}
在id=UUID.randomUUID().toString();一直报错；
哪位大神能解释一下上段代码的意思和具体怎么改啊
jsp里报错HTTP Status 500 - Request processing failed; nested exception is java.lang.NumberFormatException: null
type Exception report
message Request processing failed; nested exception is java.lang.NumberFormatException: null
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NumberFormatException: null
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:560)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
com.record.filter.TestFilter.doFilter(TestFilter.java:45)
root cause
java.lang.NumberFormatException: null
id 定义为String 类型
UUID.randomUUID().toString() 使用uuid随机生成字符串
Integer id=new Integer(request.getParameter("id"));
id = UUID.randomUUID().toString();
你的id定义的是Int类型 接收的却是一个String类型的值 当然会报错 这里你需要将 UUID.randomUUID().toString()转换成int类型才可以
Intege UUID.randomUUID().toString().arseInt(s)
1.500错误 NumberFormatException是因为
对于这句request.getParameter("id") 做个是否为null判断，以及是否为整数型进行判断。然后再进行Integer转化，
2.报错的位置是因为id定义为Integer类型，也不可能被赋值为UUID