线程“main”java中出现异常。util。NoSuchElementException:未找到行3[重复]

在此代码中,引发以下异常:

Exception in thread "main" java.util.NoSuchElementException: No line found
    at java.util.Scanner.nextLine(Scanner.java:1540)
    at com.cristianvalero.filetransfers.main.client.Client.askToDo(Client.java:98)
    at com.cristianvalero.filetransfers.main.client.Client.run(Client.java:64)
    at com.cristianvalero.filetransfers.main.client.Client.main(Client.java:36)   

引发错误的方法:

private String askToDo()
{
    Scanner teclado = new Scanner(System.in);
    System.out.print("What would you like to do? [help]: ");
    String a = teclado.nextLine().toLowerCase();
    teclado.close();
    return a;
}

但在这段比其他代码先执行的代码中,没有抛出任何错误。

private void setConnection() //Type of bookmarks "servers":["casa:1.1.1.1:3306", "trabajo:1.1.1.1:7809"]
{
    Scanner teclado = new Scanner(System.in);

    System.out.print("New server [N] or Connect previous server [P]: ");
    final String typed = teclado.nextLine().toLowerCase();

    if (typed.equals("n"))
        noHaveServers(teclado);
    else if (typed.equals("p"))
    {
        if (ServerList.getAllServers(CONFG).size() == 0)
            noHaveServers(teclado);
        else
            haveServers(teclado);
    }
    else
    {
        System.out.println("Sorry, I can't understand you.");
        teclado.close();
        setConnection();
    }

    teclado.close();
}

PD:此方法位于对Thread进行扩展的客户端类中,并从run()方法调用。