jsp的问题

Question

int photoshu=0 ;
if (request.getAttribute("photoshu")!=null){ 
      
      photoshu = ((Integer) request.getAttribute("photoshu")).intValue(); 
      
          
        } <%=photoshu%>

Answer 1

报这个错the local variable photo may not have been initialized

Answer 2

变量没有初始化 
<%!  int photoshu=0; %>
<%
if (request.getAttribute("photoshu")!=null){
     
      photoshu = ((Integer) request.getAttribute("photoshu")).intValue();
     
         
        }
%><%=photoshu%>

Answer 3

当 photoshu==null时就要抛空值针啦

Answer 4

<c:if test="${requestScope.photoshu!=null}">
    ${requestScope.photoshu}
</c:if>