关于连接数据库的问题

Question

各位大侠，最近学习安卓，用Strust2写了个服务器来访问SQL sever 2008数据库，本机测试没问题，app安装到手机然后用局域网，也没问题，但是放到服务器之后，就提示

 The TCP/IP connection to the host localhost, port 1433 has failed. Error: Connection refused: connect. Please verify the connection properties and check that a SQL Server instance is running on the host and accepting TCP/IP connections at the port, and that no firewall is blocking TCP connections to the port.

SQL的TCP/IP我已经开启了，JDBC包也放到tomcat的lib里了，防火墙也已经关闭了，但就是获取不了连接，请问这是什么原因？下面是连接数据库的代码：

 public class DBConnect {
    private static  String driver="com.microsoft.sqlserver.jdbc.SQLServerDriver";
    private static  String url="jdbc:sqlserver://localhost:1433;DatabaseName=WanShang";
    static Connection con;

    public static Connection getCon(){
       try{
           Class.forName(driver);
           con = DriverManager.getConnection(url,"no2","123");
       }catch(Exception e){
           e.printStackTrace();
       }
       return con;
    }

    public static void  closeCon(Connection con){
       try{
           if(con!=null || !con.isClosed()){
               con.close();
           }
       }catch(Exception e){
           e.printStackTrace();
       }
    }
}

Answer 1

是在外网访问内网数据库吗，如果是的话，你的交换机或路由可能阻止你访问内网