import java.sql.*; import java.io.*; import java.util.regex.*;
public class test{ public static void main(String[] args){ try{ String s = ""; while(!s.equals("q")){ System.out.print("input:"); DataInputStream in = new DataInputStream(new BufferedInputStream(System.in)); s = in.readLine(); System.out.println("your input is :"+s); String check = "^([a-z0-9A-Z]+[-|\\.]?)+[a-z0-9A-Z]@([a-z0-9A-Z]+(-[a-z0-9A-Z]+)?\\.)+[a-zA-Z]{2,}$"; Pattern regex = Pattern.compile(check); Matcher matcher = regex.matcher(s); boolean isMatched = matcher.matches(); if(isMatched){ System.out.println("it's a email"); }else{ System.out.println("it's not a email"); } } }catch(Exception e){ System.out.println("error"+e.getMessage()); } } } 
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