我的问题

package db;

import java.sql.*;
import java.util.*;
import vo.*;

public class DBManager {

private static final String driver = "org.gjt.mm.mysql.Driver";
private static final String url = "jdbc:mysql://localhost:3306/dreamshop";
private static final String cmdsql = "select * from shop_member_info";
private static final String lable = "account,address,age,date_time,email,pwd";
private static DBManager dbManager = null;
private Connection conn = null;

private DBManager() {
try {
Class.forName(driver).newInstance();
conn = DriverManager.getConnection(url);
}
catch (Exception ex) {
ex.printStackTrace();
}
}

public static synchronized DBManager getInitialization() {
if (dbManager == null) {
dbManager = new DBManager();
}
return dbManager;
}
public ArrayList getLable(){
ArrayList lableList = new ArrayList();
lableList.add("account");
lableList.add("address");
lableList.add("age");
lableList.add("date_time");
lableList.add("email");
lableList.add("pwd");
return lableList;
}

/**
* 获得表中的数据
* @return
*/
public ArrayList getValueInfo() throws SQLException {
UserVO userVO = null ;
ArrayList valueList = new ArrayList();
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(cmdsql);
while(rs.next()){
ArrayList list=new ArrayList();
Iterator it=this.getLable().iterator();
while (it.hasNext()){
String value=rs.getString(it.next().toString());
list.add(value);
}
valueList.add(list);
}
return valueList;
}

public static void main(String[] args) throws SQLException {
DBManager db = DBManager.getInitialization();
ArrayList valueList=db.getValueInfo();
Iterator it=valueList.iterator();
while(it.hasNext()){
ArrayList list=(ArrayList)it.next();
Iterator row=list.iterator();
System.out.println(list.size());
while(row.hasNext()){
System.out.print(" "+row.next());
}
System.out.println();
}
}

}