编写Java程序验证字符串是否为合法的邮箱地址(修改规则:要求@前面必须是一个标识符)
时间: 2024-05-30 08:13:02 浏览: 10
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class EmailValidator {
public static void main(String[] args) {
String email = "example@domain.com";
boolean isValid = isValidEmail(email);
System.out.println(email + " is " + (isValid ? "valid" : "invalid") + " email address.");
}
public static boolean isValidEmail(String email) {
String regex = "^[a-zA-Z0-9_]+@[a-zA-Z0-9]+(\\.[a-zA-Z0-9]+)+$";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(email);
if (matcher.matches()) {
String[] parts = email.split("@");
if (parts.length == 2) {
String identifier = parts[0];
String domain = parts[1];
if (identifier.matches("^[a-zA-Z]+[a-zA-Z0-9_]*$")) {
return true;
}
}
}
return false;
}
}
// 示例输出:
// example@domain.com is valid email address.