过滤出21岁的员工

import java.util.List;
import java.util.Optional;
import java.util.stream.Stream;
public class FindFirstDemo {
public static void main(String[] args) {
// 获取公共类的测试数据
List<Employee> list = Employee.getEmpList();
Stream<Employee> stream = list.stream(); // 获取集合流对象
// 过滤出21岁的员工
stream = stream.filter(people -> people.getAge() == 21);
Optional<Employee> young = stream.findFirst(); // 获取第一个元素
Employee emp = young.get(); // 获取员工对象
System.out.println(emp); // 输出结果
}
}