为什么执行这个数据库连接程序没有反应？（没有报错，就单纯没反应）

Question

package com.java.util;

import java.sql.Connection;
import java.sql.DriverManager;

public class DbUtil {

public Connection getCon() throws Exception {
    Class.forName(PropertiesUtil.getValue("jdbcName"));
    Connection con = DriverManager.getConnection(PropertiesUtil.getValue("dbUrl"), PropertiesUtil.getValue("dbUserName"), PropertiesUtil.getValue("dbPassword"));
    return con;
}

public void closeCon(Connection con) throws Exception {
    if(con!=null) {
        con.close();
    }
}

public static void main(String[] args) {
    DbUtil dbUtil = new DbUtil();
    try {
        dbUtil.getCon();
        System.out.println("数据库连接成功");
    } catch (Exception e) {
        // TODO Auto-generated catch block
        System.out.println("no");
        e.printStackTrace();
    }
}

}