JDBC中遍历结果集对象ResultSet

悠悠 2023-05-30 09:28 3阅读 0赞

主要步骤：

1.  游标向下移动
2.  判断是否有数据
3.  获取数据

主要遍历部分：

ResultSet rs = stmt.executeQuery(sql);
                while (rs.next()) { 
                    int id = rs.getInt(1);
                    String name = rs.getString("name");
                    double balance = rs.getDouble(3);
                    System.out.println(id + name + balance);
                }

package week01;
    
    import java.sql.*;
    /* * * */
    public class demo5 { 
        public static void main(String[] args) { 
            Connection conn = null;
            Statement stmt = null;
    
            try { 
                Class.forName("com.mysql.jdbc.Driver");
                conn = DriverManager.getConnection("jdbc:mysql:///db1", "root", "132580");
                stmt = conn.createStatement();
                String sql = "select * from acccount";
                ResultSet rs = stmt.executeQuery(sql);//先获取一次结果集对象
    //-------------------------------------------------------------
                while (rs.next()) { //循环判断下一个结果集是否为空
                    int id = rs.getInt(1);//如果不为空就获取数据
                    String name = rs.getString("name");
                    double balance = rs.getDouble(3);
                    System.out.println(id + name + balance);
                }
    //--------------------------------------------------------------- 
            } catch (ClassNotFoundException e) { 
                e.printStackTrace();
            } catch (SQLException e) { 
                e.printStackTrace();
            } finally { 
                if (conn != null) { 
                    try { 
                        conn.close();
                    } catch (SQLException e) { 
                        e.printStackTrace();
                    }
                }
                if (stmt != null) { 
                    try { 
                        stmt.close();
                    } catch (SQLException e) { 
                        e.printStackTrace();
                    }
                }
            }
        }
    }