????2???Щ???????????

public class Chanage {
 //int to String
 public static String IntToString(int i){
  String s = Integer.toString(i);
  return s;
 }
 
 //String to int
 public static int StringToInt(String s){
  int i = Integer.parseInt(s);
  return i;
 }
}

????3???????????

import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import com.mysql.jdbc.Connection;

class ConnMySQL {
 Connection conn;
 Statement stmt;
 ResultSet rs1;
 int rs2;

 public void connection() throws Exception{
  String db = "meeting";
  String driver = "com.mysql.jdbc.Driver";
  String url = "jdbc:mysql://172.16.3.9:3306/"+db;
  String uname = "admin";
  String pwd = "itserver";
 
  //????????
  Class.forName(driver);
  //?????????
  conn = (Connection) DriverManager.getConnection(url?? uname?? pwd);
 
  if(!conn.isClosed()){
   //System.out.println("??????!");
  }
 }
 
 
 //??в??????????ResultSet????
 public void  executeSql0(String sql) throws SQLException{
 
  //?????????????????sql???
  stmt = conn.createStatement();
  //???sql
  rs1 = stmt.executeQuery(sql);

  while(rs1.next()){
   String name = rs1.getString("meetingId");
   String subject = rs1.getString("e164");
   String regionName = rs1.getString("state");
   System.out.println(name+" "+subject+" "+regionName);
  }
  rs1.close();
 }
 
 //??в??????????ResultSet????
 public void  executeSql1(String sql) throws SQLException{
 
  //?????????????????sql???
  stmt = conn.createStatement();
  //???sql
  rs1 = stmt.executeQuery(sql);
 
  while(rs1.next()){
   String id = rs1.getString("id");
   String subject = rs1.getString("subject");
   String startTime = rs1.getString("startTime");
   String endTime = rs1.getString("endTime");
   String organiger = rs1.getString("organiger");
   String status = rs1.getString("status");
   System.out.println(id+" "+subject+" "+startTime+" "+endTime+" "+organiger+" "+status);
  }
  rs1.close();
  conn.close();
 }
 
 
 //???????????????int????
 public void executeSql2(String sql) throws SQLException{
  stmt = conn.createStatement();
  rs2 = stmt.executeUpdate(sql);
 
  stmt.close();
  conn.close();
 }
}