import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); String str = scanner.next(); String emailMatcher="[a-zA-Z0-9]+@[a-zA-Z0-9]+\\.[a-zA-Z0-9]+"; //write your code here...... scanner.close(); //可以利用matches()方法进行正则匹配 System.out.println(str.matches(emailMatcher) ? "邮箱格式合法" : "邮箱格式不合法"); } }