Хранить SSLSocketFactory как статическое поле

Question

Я использую следующий фрагмент кода в моем проекте Android для подключения к серверу tomcat в нескольких действиях, и я хочу переместить его в другой класс - инкапсулируйте этот фрагмент кода. По инкапсуляции мне не нужно загружать и создавать сертификаты, хранилища ключей и доверенные все соединения, как раньше.

 URL url; 
     HttpsURLConnection connection = null; 
     try { 
      // Load CAs from an InputStream 
      CertificateFactory cf = CertificateFactory.getInstance("X.509"); 
      InputStream caInput = new BufferedInputStream(getAssets().open("my_certificate.crt")); 
      Certificate ca = cf.generateCertificate(caInput); 

      // Create a KeyStore containing our trusted CAs 
      String keyStoreType = KeyStore.getDefaultType(); 
      KeyStore keyStore = KeyStore.getInstance(keyStoreType); 
      keyStore.load(null, null); 
      keyStore.setCertificateEntry("ca", ca); 

      // Create a TrustManager that trusts the CAs in our KeyStore 
      String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm(); 
      TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm); 
      tmf.init(keyStore); 

      // Create an SSLContext that uses our TrustManager 
      SSLContext context = SSLContext.getInstance("TLS"); 
      context.init(null, tmf.getTrustManagers(), null); 

      String urlParameters = SOME_PARAMETERS; 
      url = new URL(SOME_URL); 
      connection = (HttpsURLConnection) url.openConnection(); 
      connection.setSSLSocketFactory(context.getSocketFactory()); 

      connection.setUseCaches(false); 
      connection.setDoInput(true); 
      connection.setDoOutput(true); 

      connection.setRequestMethod("POST"); 
      connection.setFixedLengthStreamingMode(urlParameters.getBytes().length); 
      connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 

      PrintWriter out = new PrintWriter(connection.getOutputStream()); 
      out.print(urlParameters); 
      out.close(); 

Это нормально Венна я двигаюсь первые 4 подпункты к способу нового класса и сохранить результат первого вызова в качестве статического поля? Пример

public class ConnectionPreparer { 
    private static SSLSocketFactory sslSocketFactory; 
    private Context context; 
    public ConnectionPreparer (Context context){ 
     this.context = context; 
    } 
    private SSLSocketFactory getSSLSocketFactory(){ 
     if(sslSocketFactory==null){ 
      CertificateFactory cf = CertificateFactory.getInstance("X.509"); 
      InputStream caInput = new BufferedInputStream(context.getAssets().open("my_certificate.crt")); 
      Certificate ca = cf.generateCertificate(caInput); 

      // Create a KeyStore containing our trusted CAs 
      String keyStoreType = KeyStore.getDefaultType(); 
      KeyStore keyStore = KeyStore.getInstance(keyStoreType); 
      keyStore.load(null, null); 
      keyStore.setCertificateEntry("ca", ca); 

      // Create a TrustManager that trusts the CAs in our KeyStore 
      String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm(); 
      TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm); 
      tmf.init(keyStore); 

      // Create an SSLContext that uses our TrustManager 
      SSLContext context = SSLContext.getInstance("TLS"); 
      context.init(null, tmf.getTrustManagers(), null); 

      sslSocketFactory = context.getSocketFactory(); 
     } 
     return sslSocketFactory; 
    } 
    public HttpsURLConnection prepareConnection(){ 
     URL url = SOME_URL;    
     HttpsURLConnection connection = (HttpsURLConnection) url.openConnection(); 
     connection.setSSLSocketFactory(getSSLSocketFactory()); 
     // and so on 
    } 
} 

Если это нехорошо, чем почему? Если это нормально, я счастлив.

Благодарим за внимание!

Answer 1

Yap, это сработало. Вот результат класса.

import android.content.Context; 
import android.util.Log; 

import java.io.BufferedInputStream; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.PrintWriter; 
import java.io.UnsupportedEncodingException; 
import java.net.MalformedURLException; 
import java.net.URL; 
import java.net.URLEncoder; 
import java.security.KeyStore; 
import java.security.cert.Certificate; 
import java.security.cert.CertificateFactory; 
import java.util.Scanner; 

import javax.net.ssl.HttpsURLConnection; 
import javax.net.ssl.SSLContext; 
import javax.net.ssl.SSLSocketFactory; 
import javax.net.ssl.TrustManagerFactory; 

/** 
* Created by Rinomancer on 20.08.2015. 
*/ 
public class ConnectionBuilder { 
    private static SSLSocketFactory sslSocketFactory; 
    private Context context; 
    private URL url; 
    private String parameters = ""; 
    private String response; 
    private HttpsURLConnection connection; 

    public ConnectionBuilder() { 

    } 

    public ConnectionBuilder(Context context, URL url) { 
     this.context = context; 
     this.url = url; 
    } 

    private SSLSocketFactory getSSLSocketFactory() throws Exception { 
     if (sslSocketFactory == null) { 
      CertificateFactory cf = CertificateFactory.getInstance("X.509"); 
      InputStream caInput = new BufferedInputStream(context.getAssets().open("my_certificate.crt")); 
      Certificate ca = cf.generateCertificate(caInput); 

      // Create a KeyStore containing our trusted CAs 
      String keyStoreType = KeyStore.getDefaultType(); 
      KeyStore keyStore = KeyStore.getInstance(keyStoreType); 
      keyStore.load(null, null); 
      keyStore.setCertificateEntry("ca", ca); 

      // Create a TrustManager that trusts the CAs in our KeyStore 
      String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm(); 
      TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm); 
      tmf.init(keyStore); 

      // Create an SSLContext that uses our TrustManager 
      SSLContext context = SSLContext.getInstance("TLS"); 
      context.init(null, tmf.getTrustManagers(), null); 

      sslSocketFactory = context.getSocketFactory(); 
     } 
     return sslSocketFactory; 
    } 

    public ConnectionBuilder connect() throws Exception { 
     connection = null; 
     try { 
      connection = (HttpsURLConnection) url.openConnection(); 
      connection.setSSLSocketFactory(getSSLSocketFactory()); 
      connection.setConnectTimeout(5000); 

      connection.setUseCaches(false); 
      connection.setDoInput(true); 
      connection.setDoOutput(true); 

      connection.setRequestMethod("POST"); 
      connection.setFixedLengthStreamingMode(parameters.getBytes().length); 
      connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
      if (sessionId != null && !sessionId.isEmpty()) { 
       connection.setRequestProperty("Session-Id", sessionId); 
      } 

      PrintWriter out = new PrintWriter(connection.getOutputStream()); 
      out.print(parameters); 
      out.close(); 

      String response = ""; 
      Scanner inStream = new Scanner(connection.getInputStream()); 
      while (inStream.hasNextLine()) { 
       response += inStream.nextLine(); 
      } 
      this.response = response; 

      return this; 
     } finally { 
      if (connection != null) { 
       connection.disconnect(); 
      } 
     } 
    } 

    public ConnectionBuilder context(Context context) { 
     this.context = context; 
     return this; 
    } 

    public ConnectionBuilder url(URL url) { 
     this.url = url; 
     return this; 
    } 

    public ConnectionBuilder url(String url) throws MalformedURLException { 
     this.url = new URL(url); 
     return this; 
    } 

    public ConnectionBuilder parameter(String parameter, String value) throws UnsupportedEncodingException { 
     if (parameters.isEmpty()) { 
      parameters = parameter + "=" + URLEncoder.encode(value, "UTF-8"); 
     } else { 
      parameters += "&" + parameter + "=" + URLEncoder.encode(value, "UTF-8"); 
     } 
     return this; 
    } 

    public String getResponse() { 
     return response; 
    } 

    public String getHeader(String headerName) { 
     return connection.getHeaderField(headerName); 
    } 

    public int getStatusCode() throws IOException{ 
     return connection.getResponseCode(); 
    } 
} 

И использование этого класса в андроиде активности:

try { 
    ConnectionBuilder cb = new ConnectionBuilder().context(getApplicationContext()).url(YOUR_URL).parameter("parameterName",parameterValue).parameter("anotherParameter",itsValue).connect(); 
    result = cb.getResponse(); 
    } catch (Exception e){ 
     e.printStackTrace(); 
    } 

Конечно, вы можете расширить этот класс, добавив SetHeader (функциональность). Но по моему сценарию это было нецелесообразно.