OkHttp_Certificate_Pinner

/*
* OkHttp lib provide a CertificatePinner class to be added to an OkHttpClient instance. 
* The easiest way to pin a host is turn on pinning with a broken configuration and 
* read the expected configuration when the connection fails.
*/
CertificatePinner certificatePinner = new CertificatePinner.Builder()
         .add("mydomain.com", "sha256/AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=")
         .build();
     OkHttpClient client = OkHttpClient.Builder()
         .certificatePinner(certificatePinner)
         .build();
         
         
/* After a request is executed, you’ll see this message on the console: */
javax.net.ssl.SSLPeerUnverifiedException: Certificate pinning failure!
   Peer certificate chain:
     sha256/afwiKY3RxoMmLkuRW1l7QsPZTJPwDS2pdDROQjXw8ig=: CN=mydomain.com, OU=PositiveSSL
     sha256/klO23nT2ehFDXCfx3eHTDRESMz3asj1muO+4aIdjiuY=: CN=COMODO RSA Secure Server CA
     sha256/grX4Ta9HpZx6tSHkmCrvpApTQGo67CYDnvprLg5yRME=: CN=COMODO RSA Certification Authority
     sha256/lCppFqbkrlJ3EcVFAkeip0+44VaoJUymbnOaEUk7tEU=: CN=AddTrust External CA Root
   Pinned certificates for mydomain.com:
     sha256/AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
   at okhttp3.CertificatePinner.check(CertificatePinner.java)
   at okhttp3.Connection.upgradeToTls(Connection.java)
   at okhttp3.Connection.connect(Connection.java)
   at okhttp3.Connection.connectAndSetOwner(Connection.java)
   
   
/* The exception will provide you the server’s certificate public key hashes. Paste them on the CertifinatePinner and done! ✔ */
CertificatePinner certificatePinner = new CertificatePinner.Builder()
       .add("mydomain.com", "sha256/afwiKY3RxoMmLkuRW1l7QsPZTJPwDS2pdDROQjXw8ig=")
       .add("mydomain.com", "sha256/klO23nT2ehFDXCfx3eHTDRESMz3asj1muO+4aIdjiuY=")
       .add("mydomain.com", "sha256/grX4Ta9HpZx6tSHkmCrvpApTQGo67CYDnvprLg5yRME=")
       .add("mydomain.com", "sha256/lCppFqbkrlJ3EcVFAkeip0+44VaoJUymbnOaEUk7tEU=")
       .build();