/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
	    String email = "foo@bar.com";
	    int pos = email.indexOf("@"); // Se retornar -1 é um email invalido
 
	    if (pos != -1) {
	        String provedor = email.substring(pos + 1);
 
	        System.out.println(provedor);
	    } else {
	        System.err.println("Email inválido");
	    }
	}
}

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