Question

我觉得此方法签名太长。有没有更明智或更优雅的方式来重写此内容？

  private Email createMail(long actualFileSize, String from, String recipient, String title,
      String emailContent, MultipartFile attachment,
      File file) {
    Email mail = null;
    if (actualFileSize <= Long.parseLong(emailFileSizeLimit)) {
     mail = new Email(from, recipient, title,emailContent, null, file);
    } else mail = new Email(from, recipient, title,emailContent, null, null);
    return mail;
  }

Answer 1

tl; dr

if (actualFileSize <= Long.parseLong(emailFileSizeLimit)) {
    file = null;
}

return new Email(from, recipient, title,emailContent, null, file);

1）重构。如果您认为参数太多，可以将该方法划分为较小的，易于管理的方法。

if (actualFileSize <= Long.parseLong(emailFileSizeLimit)) {
    file = null;
}

createMail(from, recipient, title,emailContent, null, file);

******

private Email createMail(long actualFileSize, String from, String recipient, String 
    title, String emailContent, MultipartFile attachment, File file) {
   return new Email(from, recipient, title,emailContent, null, file);
}

2）DTO。您可以在dto中提供参数，并将其作为请求/响应传递到整个链中，并在需要时使用需要的元素。当需要创建时，可以添加更多属性。您可以通过设置员来提供它们，并在需要时通过

3）生成器。您在类中完成了逻辑，操作完成后将返回自身。您可以通过在同一类上调用不同的操作并返回结果来执行下一操作。

Mail mail = mailBuilder.addName(name).add(stuff).compile(); // will call constructor inside

4）工厂

具有包含所有方法的工厂，并让它决定调用什么方法。它可以是静态的或托管的

factory.createBasicMail(name);
factory.createFileMail(name, file);

ps：为了您的心理健康，请使用龙目岛

Answer 2

这似乎很适合Builder pattern，在这里您需要以精心的方式构造一个新对象：

public class EmailBuilder {
  private Email mail;
  private String from;
  private String recipient;
  // other properties

  public EmailBuilder withFrom(String from) {
    this.from = from;
    return this;
  }
  public EmailBuilder withRecipient(String recipient) {
    this.recipient = recipient;
    return this;
  }
  public Email send() {
    mail = new Email(from, recipient, title,emailContent, null, file);
    return mail;
  }
}

用法

Email mail = new EmailBuilder()
   .withFrom("John Doe")
   .withRecipient("Mary Doe")
   .with...
   .send();

避免/处理长方法签名的方法有哪些？

2 个答案: