Question

我正在做一个由客户端 - 服务器游戏组成的学校项目。

可以像示例1 和示例2 中所示编写Java代码：

在示例2 中，我看到通过创建3个私有方法并在构造函数中调用它们来缩短构造函数的可能性（IMHO看起来更整洁）。

哪个示例是Java中的最佳实践/推荐？

示例1 ：

public ServerConnection()
{
    private Socket serverSocket = null;
    private SSLSocket sslServerSocket = null;

    private DataOutputStream dos;
    private DataInputStream dis;
    private ObjectOutputStream oos;
    private ObjectInputStream ois;

    private DataOutputStream ssldos;
    private DataInputStream ssldis;
    private ObjectOutputStream ssloos;
    private ObjectInputStream sslois;

    try
    {
        serverSocket = new Socket("localhost", 9000);

        String password = "password";

        KeyStore trustStore = KeyStore.getInstance("JKS");
        trustStore.load(ClassLoader.getSystemResourceAsStream("SSL/mykey.jks"), password.toCharArray());
        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance("SunX509");
        trustManagerFactory.init(trustStore);

        SSLContext context = SSLContext.getInstance("TLS");
        context.init(null, trustManagerFactory.getTrustManagers(), new SecureRandom());

        SSLSocketFactory sslSocketFactory = (SSLSocketFactory)context.getSocketFactory();
        sslServerSocket = (SSLSocket) sslSocketFactory.createSocket("localhost", 9001);

        sslServerSocket.startHandshake();


        dos = new DataOutputStream(serverSocket.getOutputStream());
        dis = new DataInputStream(serverSocket.getInputStream()); 
        oos = new ObjectOutputStream(serverSocket.getOutputStream());
        ois = new ObjectInputStream(serverSocket.getInputStream()); 

        ssldos = new DataOutputStream(sslServerSocket.getOutputStream()); 
        ssldis = new DataInputStream(sslServerSocket.getInputStream()); 
        ssloos = new ObjectOutputStream(sslServerSocket.getOutputStream()); 
        sslois = new ObjectInputStream(sslServerSocket.getInputStream()); 

    }
    catch (IOException | KeyStoreException | NoSuchAlgorithmException | CertificateException | KeyManagementException e)
    {
        System.out.println("ServerConnection 2 " + e.getMessage());
    }
}

示例2 ：

public ServerConnection()
{
    private Socket serverSocket = null;
    private SSLSocket sslServerSocket = null;

    private DataOutputStream dos;
    private DataInputStream dis;
    private ObjectOutputStream oos;
    private ObjectInputStream ois;

    private DataOutputStream ssldos;
    private DataInputStream ssldis;
    private ObjectOutputStream ssloos;
    private ObjectInputStream sslois;

    try
    {
        serverSocket = new Socket("localhost", 9000);

        keyMethod();           

        SSLContext context = SSLContext.getInstance("TLS");
        context.init(null, trustManagerFactory.getTrustManagers(), new SecureRandom());           
        SSLSocketFactory sslSocketFactory = (SSLSocketFactory)context.getSocketFactory();
        sslServerSocket = (SSLSocket) sslSocketFactory.createSocket("localhost", 9001);  
        sslServerSocket.startHandshake();

        setStreams();

        setSSLStreams();            
    }
    catch (IOException | KeyStoreException | NoSuchAlgorithmException | CertificateException | KeyManagementException e)
    {
        System.out.println("ServerConnection 2 " + e.getMessage());
    }

    private void keyMethod()
    {
        String password = "password";
        KeyStore trustStore = KeyStore.getInstance("JKS");
        trustStore.load(ClassLoader.getSystemResourceAsStream("SSL/mykey.jks"), password.toCharArray());
        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance("SunX509");
        trustManagerFactory.init(trustStore);
    }

    private void setStreams()
    {
        dos = new DataOutputStream(serverSocket.getOutputStream());
        dis = new DataInputStream(serverSocket.getInputStream()); 
        oos = new ObjectOutputStream(serverSocket.getOutputStream());
        ois = new ObjectInputStream(serverSocket.getInputStream()); 
    }

    private void setSSLStreams()
    {
        ssldos = new DataOutputStream(sslServerSocket.getOutputStream()); 
        ssldis = new DataInputStream(sslServerSocket.getInputStream()); 
        ssloos = new ObjectOutputStream(sslServerSocket.getOutputStream()); 
        sslois = new ObjectInputStream(sslServerSocket.getInputStream());  
    }
}

Answer 1

示例2是您最好的选择，因为它遵循最佳实践指南，更易于阅读，反过来又使您的代码更清晰。将代码片段转换为名称解释方法目的的方法也是理想的。有几个原因可以让你想要简短明了的方法：

首先，它增加了其他方法在方法细粒度时可以使用方法的机会。
其次，它允许更高级别的方法更像是一系列注释。当方法细化时，覆盖也会更容易。

以Martin Fowler在博客上提供的例子为例：

碎片代码：

void printOwing() {
  printBanner();

  //print details
  System.out.println ("name:  " + _name);
  System.out.println ("amount " + getOutstanding());
}

重构代码：

void printOwing() {
  printBanner();
  printDetails(getOutstanding());
}

void printDetails (double outstanding) {
  System.out.println ("name:  " + _name);
  System.out.println ("amount " + outstanding);
}

这也有助于其他可能查看您的代码的人快速了解正在发生的事情。

您可以在Refactoring了解更多福勒先生的博客。另请参阅SourceMaking博客，了解您应该提取方法的原因。

Answer 2

通常，除非有正当理由，否则指南是尝试拆分任何超过100 LOC的功能。有理由的案例包括

此功能的性能要求非常高
分裂导致大量参数传递并且看起来多余
该功能在逻辑上是单件操作

等

多种方法或单一（但长）方法

2 个答案: