基于OKHttp实现对Https的支持

OKHttp版本：OKHttp3.6.0

准备工作：

Module的build.gradle文件中，添加依赖

dependencies {
compile 'com.squareup.okhttp3:okhttp:3.6.0'

}

实现步骤：



第一步：在Module的src ---> main下新建一个assets的文件夹，然后将证书文件放入（证书文件一般由后台人员通过jdk命令制作，然后部署在服务器上，我们需要的是后缀名为.cer的文件），如图：



第二步：提供一个构造方法，将证书解析成流以参数形式传入，如下：

private static OkHttpClient okHttpClient;

/**
* 获取oKHttpClient
* certificates 证书信息 没有就传null
* @return
*/
public static OkHttpClient getOkHttpClient(Application appContext，InputStream... certificates) {
if (okHttpClient == null) {

File sdcache = appContext.getExternalCacheDir();
int cacheSize = 10 * 1024 * 1024;
OkHttpClient.Builder builder = new OkHttpClient.Builder()
.connectTimeout(20, TimeUnit.SECONDS)
.writeTimeout(20, TimeUnit.SECONDS)
.readTimeout(20, TimeUnit.SECONDS)
.cache(new Cache(sdcache.getAbsoluteFile(), cacheSize));
if (certificates != null){
builder.sslSocketFactory(getSSLSocketFactory(certificates));
}
okHttpClient = builder.build();
}
return okHttpClient;
}

/**
* 获取SSLSocketFactory
*
* @param certificates 证书流文件
* @return
*/
private static SSLSocketFactory getSSLSocketFactory(InputStream... certificates) {
try {
CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
keyStore.load(null);
int index = 0;
for (InputStream certificate : certificates) {
String certificateAlias = Integer.toString(index++);
keyStore.setCertificateEntry(certificateAlias, certificateFactory.generateCertificate(certificate));

try {
if (certificate != null)
certificate.close();
} catch (IOException e) {
}
}
SSLContext sslContext = SSLContext.getInstance("TLS");
TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
trustManagerFactory.init(keyStore);
sslContext.init(null, trustManagerFactory.getTrustManagers(), new SecureRandom());
return sslContext.getSocketFactory();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

第三步：调用第二步提供的构造方法，传入第一步的证书信息，如下：

xxxUtil.getOkHttpClient(context.getAssets().open("xxx.cer"));

这里的xxx.cer和assets下的证书文件名要一致，否则找不到证书文件。