数据库查询Util

public class DBUtils {

    private static Dao dao;
    public static String dbUrl;
    public static String dbUserName;
    public static String dbPassword;

    public static void setPassword(String password){
        dbPassword=password;
    }
    public static void  setDbUrl(String dburl){
        dbUrl = dburl;
    }
    public static void setDbUserName(String dbusername){
        dbUserName = dbusername;
    }
    public static Dao getSqlDao() {
        //if(dao==null) {  如果同时查询多个数据库，这里不能为null
            SimpleDataSource dataSource = new SimpleDataSource();
            dataSource.setJdbcUrl(dbUrl);
            dataSource.setUsername(dbUserName);
            dataSource.setPassword(dbPassword);
            dao = new NutDao(dataSource);
       // }

        return dao;
    }
    /*
    *返回查询结果
    * */
    public static List