java - 结果集关闭后，我收到“操作不允许”消息

Question

我正在提取大约 10,000 个患者 ID，同时在执行加密后我想将它们插入到另一个表中，但出现此错误

java.sql.SQLException: Operation not allowed after ResultSet closed.

Connection conn=null;
PreparedStatement pst=null;
try{
    conn = DriverManager.getConnection(constring,username,password);
    System.out.println("connected");

    Statement stmt=(Statement) conn.createStatement();

    ResultSet srs = stmt.executeQuery(
    "select patient_id from patient");

    while (srs.next()) {
        patient_id = srs.getInt("patient_id");

        System.out.println(patient_id);
        JavaApplication5 o=new JavaApplication5(key);

        g=patient_id;
        o.c=main.g;
        s=o.encrypt(o.c,key);
        System.out.println(s);
        String insert = "Insert into fyp1 (patient_id) values ('"+s+"')";
        stmt.executeUpdate(insert);
        }
    }
catch(SQLException e){System.out.println(e);

Answer 1

您需要创建另一个语句，因为第一个 ResultSet srs 在 stmt.executeUpdate(insert); 处再次运行时已关闭。

请参阅 JavaDocs 中的 ResultSet

Note: A ResultSet object is automatically closed by the Statement object that generated it when that Statement object is closed, re-executed, or is used to retrieve the next result from a sequence of multiple results.

顺便说一句。请始终发布完整的堆栈跟踪，例如以及相应的行号。