Question

jdbc Operation not allowed after ResultSet closed 出现这个错误

main函数
ResultSet rs=st.executeQuery("select * from form_url where save is NULL");
while(rs.next()){
url1=rs.getString("url");
id=getInt("id");
test.downloadFile(url1,st,id);

}

downloadfile函数中
st.executeUpdate("update form_url set save_path = 12 where id = id");

具体错误如下

Operation not allowed after ResultSet closed
java.sql.SQLException: Operation not allowed after ResultSet closed
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:910)
at com.mysql.jdbc.ResultSet.checkClosed(ResultSet.java:666)
at com.mysql.jdbc.ResultSet.next(ResultSet.java:7274)
at liuyi.test.main(test.java:86)

Answer 1

错误上说你ResultSet 已经关了，不能操作了。你应该是换了执行语句所以ResultSet 关了，我记得ResultSet 的实现是基于游标的，换了查询游标就更新了吧。
你可以试试建个st2，来传到downloadFile里面。

Answer 2

main函数
ResultSet rs=st.executeQuery("select * from form_url where save is NULL");
while(rs.next()){
url1=rs.getString("url");
id=getInt("id");
test.downloadFile(url1,st,id);

}

rs.rs.close();