验证qq合法性

package 验证qq正确性;
import java.util.Scanner;
public class 验证qq正确性 {

public static void main(String[] args)
{
String regex ="[1-9][0-9]{4,14}";
System.out.println("请输入你的qq号");
String w=null;
String d=System(w);
boolean flag=checkqq(d,regex);
if(flag==true)
System.out.println("该qq合法");
else
System.out.println("该qq不合法");
}
public static boolean checkqq(String email,String emailregex)//这是验证是否正确函数
{
return email.matches(emailregex);
}
public static String System(String i)//这是输入函数
{
Scanner sc=new Scanner(System.in);
i=sc.next();
return i;
}
}