java - 如何修改数组列表中的元素

Question

我创建了下面的 arrayLIST 。我想修改djohn@gmail.com 的电话号码。你能告诉我如何修改它吗？提前致谢

 private static List<Customer> customers;
{
    customers = new ArrayList();
    customers.add(new Customer(101, "John", "Doe", "djohn@gmail.com", "121-232-3435"));
    customers.add(new Customer(201, "Russ", "Smith", "sruss@gmail.com", "343-545-2345"));
    customers.add(new Customer(301, "Kate", "Williams", "kwilliams@gmail.com", "876-237-2987"));

}

Answer 1

使用 Java 8 流，使用谓词查找客户，并使用 Optional.ifPresent() 更新值。

customers.stream()
         .filter(customer -> "djohn@gmail.com".equals(customer.getEmail()))
         .findFirst()
         .ifPresent(customer -> customer.setPhoneNumber(2222222));