ResultSet遍历过程中修改自身数据，不会改变循环的过程

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class TestTbl {
    public static void main(String[] args) throws Exception {
        Connection tXdConn = Conn.getTXdConn();
        String sql1 = "select * from tbl ";
        
        PreparedStatement statement = tXdConn.prepareStatement(sql1);
        ResultSet resultSet = statement.executeQuery();
        while(resultSet.next()){
            String content1 = resultSet.getString("content1");
            if(content1.equals("b")){
                String sql2 = "update tbl set content1 = ‘c‘";
                PreparedStatement statement2 = tXdConn.prepareStatement(sql2);
                statement2.executeUpdate();
                statement2.close();
                String string = resultSet.getString("content1");
                
                System.out.println("update:" + string);
            }
            System.out.println(content1);
        }
        resultSet.close();
        statement.close();
        tXdConn.close();
    }
}