jsp+JavaBean使用list查询信息无法获得结果

Question

JavaBean中的方法：
public List queryAllStu() {
List stus = new ArrayList();
try {
pstmt = conn.prepareStatement("select * from studentinfo");
ResultSet rs = pstmt.executeQuery();
while (rs.next()) {
stuInfo stu = new stuInfo();
stu.setId(rs.getInt(1));
stu.setNicheng(rs.getString(2));
stu.setTruename(rs.getString(3));
stu.setXb(rs.getByte(4));
if (rs.getDate(5) != null) {
stu.setCsrq(rs.getDate(5).toString());
}
stu.setZy(rs.getString(6));
if (rs.getString(7) != null) {
stu.setKc(rs.getString(7).split("&"));
}
if (rs.getString(8) != null) {
stu.setXq(rs.getString(8).split("&"));
}
stu.setBz(rs.getString(9));
stus.add(stu);
}
return stus;
} catch (SQLException e) {
e.printStackTrace();
return null;
}
}
jsp页面：

/jsp:useBean
<%
List stus=stuInfoService.queryAllStu();
if(stus==null)
out.print("null");
else
out.print(stus.size());
%>

数据库中有信息但每次都返回null怎么回事

Answer 1

你看下控制台，，，截图发上来，，，八成是异常了，，然后

  e.printStackTrace();
            return null;