HttpClient自定义SSL上下文

使用安全套接字层，可以在客户端和服务器之间建立安全连接。它有助于保护敏感信息，如信用卡号，用户名，密码，别针等。

可以使用HttpClient库创建自己的SSL上下文，从而使连接更安全。按照下面给出的步骤使用HttpClient库自定义SSLContext -

第1步 - 创建SSLContextBuilder对象
SSLContextBuilder是SSLContext对象的构建器。使用SSLContexts类的custom()方法创建对象。

//Creating SSLContextBuilder object
SSLContextBuilder SSLBuilder = SSLContexts.custom();

第2步 - 加载密钥库
在路径Java_home_directory/jre/lib/security/中，可以找到名为cacerts的文件。将其保存为密钥库文件(扩展名为.jks)。使用SSLContextBuilder类的loadTrustMaterial()方法加载密钥库文件及其密码(默认为changeit)。

//Loading the Keystore file
File file = new File("mykeystore.jks");
SSLBuilder = SSLBuilder.loadTrustMaterial(file, "changeit".toCharArray());

第3步 - 构建SSLContext对象
SSLContext对象表示安全套接字协议实现。使用build()方法构建SSLContext。

//Building the SSLContext
SSLContext sslContext = SSLBuilder.build();

第4步 - 创建SSLConnectionSocketFactory对象

SSLConnectionSocketFactory是用于TSL和SSL连接的分层套接字工厂。使用此方法，可以使用受信任证书列表验证https服务器并验证给定的https服务器。

可以通过多种方式创建它。根据创建SSLConnectionSocketFactory对象的方式可允许所有主机，仅允许自签名证书，仅允许特定协议等。

要仅允许特定协议，请通过传递SSLContext对象，表示需要支持的协议的字符串数组，表示需要支持的密码套件的字符串数组以及表示其构造函数的HostnameVerifier对象来创建SSLConnectionSocketFactory对象。

new SSLConnectionSocketFactory(sslcontext, new String[]{"TLSv1"}, null,    
   SSLConnectionSocketFactory.getDefaultHostnameVerifier());

要允许所有主机，请通过传递SSLContext对象和NoopHostnameVerifier对象来创建SSLConnectionSocketFactory对象。

//Creating SSLConnectionSocketFactory SSLConnectionSocketFactory object
SSLConnectionSocketFactory sslConSocFactory = new SSLConnectionSocketFactory(sslcontext, new NoopHostnameVerifier());

第5步 - 创建一个HttpClientBuilder对象
使用HttpClients类的custom()方法创建HttpClientBuilder对象。

//Creating HttpClientBuilder
HttpClientBuilder clientbuilder = HttpClients.custom();

第6步 - 设置SSLConnectionSocketFactory对象
使用setSSLSocketFactory()方法将SSLConnectionSocketFactory对象设置为HttpClientBuilder。

//Setting the SSLConnectionSocketFactory
clientbuilder = clientbuilder.setSSLSocketFactory(sslConSocFactory);

第7步 - 构建CloseableHttpClient对象
通过调用build()方法构建CloseableHttpClient对象。

//Building the CloseableHttpClient
CloseableHttpClient httpclient = clientbuilder.build();

第8步 - 创建一个HttpGet对象
HttpGet类表示HTTP GET请求，该请求使用URI检索给定服务器的信息。

通过传递表示URI的字符串来实例化HttpGet类来创建HTTP GET请求。

//Creating the HttpGet request
HttpGet httpget = new HttpGet("https://zyiz.net/");

第9步 - 执行请求
使用execute()方法执行请求。

//Executing the request
HttpResponse httpresponse = httpclient.execute(httpget);

示例

以下示例演示了SSLContrext的自定义 -

import java.io.File;
import javax.net.ssl.SSLContext;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.SSLContexts;
import org.apache.http.util.EntityUtils;

public class ClientCustomSSL {

   public final static void main(String[] args) throws Exception {

      //Creating SSLContextBuilder object
      SSLContextBuilder SSLBuilder = SSLContexts.custom();

      //Loading the Keystore file
      File file = new File("mykeystore.jks");
      SSLBuilder = SSLBuilder.loadTrustMaterial(file,
         "changeit".toCharArray());

      //Building the SSLContext usiong the build() method
      SSLContext sslcontext = SSLBuilder.build();

      //Creating SSLConnectionSocketFactory object
      SSLConnectionSocketFactory sslConSocFactory = new SSLConnectionSocketFactory(sslcontext, new NoopHostnameVerifier());

      //Creating HttpClientBuilder
      HttpClientBuilder clientbuilder = HttpClients.custom();

      //Setting the SSLConnectionSocketFactory
      clientbuilder = clientbuilder.setSSLSocketFactory(sslConSocFactory);

      //Building the CloseableHttpClient
      CloseableHttpClient httpclient = clientbuilder.build();

      //Creating the HttpGet request
      HttpGet httpget = new HttpGet("https://zyiz.net/");

      //Executing the request
      HttpResponse httpresponse = httpclient.execute(httpget);

      //printing the status line
      System.out.println(httpresponse.getStatusLine());

      //Retrieving the HttpEntity and displaying the no.of bytes read
      HttpEntity entity = httpresponse.getEntity();
      if (entity != null) {
         System.out.println(EntityUtils.toByteArray(entity).length);
      } 
   }
}

执行上面示例代码，得到以下结果：

HTTP/1.1 200 OK
1270