Write a java program to check whether a given number is a valid mobile number or not

import java.util.regex.*;
class RegexDemo6
{
	public static void main(String[] args)
	{
		Pattern p=Pattern.compile("(0/91)?[7-9][0-9]{9}");
		Matcher m=p.matcher(args[0]);
		if(m.find() && m.group().equals(args[0]))
		{
			System.out.println("valid mobile number");
		}
		else
		{
			System.out.println("invalid number");
		}
	}
}

Output:

1st run : java RegexDemo6 9439202111
valid mobile number
2nd run : java RegexDemo6 929292929292
invalid number

Java Regular expression program to check whether a given mail id is valid or invalid mail id.