汉中市网站建设,爱墙 网站怎么做,免费网站报价单怎么做,网站建设费用的财务核算权限太多#xff0c;想用简单自定义标签来控制#xff0c;但遇到一个头疼的问题#xff0c;不能用autowird自动注入spring管理的bean#xff0c;让人恼火#xff1b;
经过周折#xff0c;终于解决问题#xff0c;与大家一起分享#xff0c;可能不是最好的方法#xf…权限太多想用简单自定义标签来控制但遇到一个头疼的问题不能用autowird自动注入spring管理的bean让人恼火
经过周折终于解决问题与大家一起分享可能不是最好的方法希望有更好方法的人能推荐给我谢谢
下面这样出现空指针异常
package com.bookstore.utils;import com.bookstore.client.user.handler.UserHandler;
import com.bookstore.commons.beans.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.SimpleTagSupport;
import java.io.IOException;Component
public class LoginTag extends SimpleTagSupport {Autowiredprivate UserHandler userHandler;public void doTag() throws JspException, IOException {PageContext context (PageContext) this.getJspContext();HttpServletResponse response (HttpServletResponse) context.getResponse();HttpServletRequest request (HttpServletRequest) context.getRequest();User user (User) context.getSession().getAttribute(login_user);System.out.println(userHandler);if(usernull){System.out.println(aaaaaaaaaaaaaaaaaaaa);User user1 userHandler.autologin(request);System.out.println(user1);if(user1null){System.out.println(BBBBBBBBBBbbbbb);response.sendRedirect(request.getContextPath()/client/error/privilege.jsp);}}}
}而且显示注入成功点击还能跳转 换一种解决方法使用下面这样可以解决 PageContext pageContext (PageContext) this.getJspContext();ServletContext servletContext pageContext.getServletContext();WebApplicationContext wac WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext);UserHandler userHandler (UserHandler) wac.getBean(userHandler);
不明白前边的方法为什么不行希望有答案的推荐给我万分感谢
