下面这个空指针问题怎么解决？感谢

[moxiu0514]

org.apache.jasper.JasperException: An exception occurred processing JSP page /iframe/head.jsp at line 9

6: <%
7: String path = request.getContextPath();
8: String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
9: List sysList=sys.getSiteInfo();
10: List affList=abc.getAllAffiche();
11: List newsList=news.getIndexNews();
12: List AllnewsList=news.getAllNews(); 


Stacktrace:
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:584)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:481)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

根源

java.lang.NullPointerException
	com.util.DBO.close(DBO.java:55)
	com.bean.SystemBean.getSiteInfo(SystemBean.java:91)
	org.apache.jsp.index_jsp._jspService(index_jsp.java:160)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

[zsyqqcom]

https://ask.csdn.net/questions/7462683?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522170686502616800188598111%2522%252C%2522scm%2522%253A%252220140713.130102334.pc%255Fall.%2522%257D&request_id=170686502616800188598111&biz_id=4&utm_medium=distribute.pc_search_result.none-task-ask_topic-2~all~first_rank_ecpm_v1~rank_v31_ecpm-2-7462683-null-null.142%5Ev99%5Econtrol&utm_term=sys.getSiteInfo&spm=1018.2226.3001.4187

[阿沐沐，]

sys 对象不一定会有值，你可以选择在sys对象接收的时候去判断值为 null 的话直接返回，或者是跳过一段逻辑