我想从数据库中select出一个int型的“sumMark”的字段的值,然后判断它是否为0.因为要将rs的值换为int型,所以通过这个语句int temp=rs.getInt("sumMark");但是有这句就报错了,各位前辈这是为什么呀?……
String sql2="select * from tb_movie where id='1'";
ResultSet rs=con.executeQuery(sql2);
int temp=rs.getInt("sumMark");
if (temp==0) {……
报错是:
org.apache.jasper.JasperException: An exception occurred processing JSP page /soap/2.jsp at line 25
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:398)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause
String sql2="select * from tb_movie where id='1'";
ResultSet rs=con.executeQuery(sql2);
int temp=rs.getInt("sumMark");
if (temp==0) {……
报错是:
org.apache.jasper.JasperException: An exception occurred processing JSP page /soap/2.jsp at line 25
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:398)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause
试试
改为
int temp=rs.getString("sumMark");
ResultSet rs=con.executeQuery(sql2);
rs.next();
int temp=rs.getInt("sumMark");
if (temp==0) {…… 要先 next 一下,确保数据库有记录啊
rs.next();
最好判断一下rs
做好NullPoiontException,的发生。。