Adding keystore

/**
* Adding ssl socket factory to okhttp builder with trusted cert
*
* @param builder OkHttpClient.Builder
*/
private void configureTrustingCertificates(OkHttpClient.Builder builder) {
        TrustManager[] trustManagers;
        TLSSocketFactory sslSocketFactory;
        try {
            trustManagers = getTrustManagers(readKeyStore());
            sslSocketFactory = new TLSSocketFactory(trustManagers);

            builder.sslSocketFactory(sslSocketFactory, (X509TrustManager) trustManagers[0]);
        } catch (GeneralSecurityException e) {
            throw new RuntimeException(e);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

  /**
    * Returns TrustManger[] initiated with keystore 
    * @param keyStore for TrustManager
    * @return  TrustManger[]
    * @throws GeneralSecurityException if no configured trust managers
    */
    private TrustManager[] getTrustManagers(KeyStore keyStore) throws GeneralSecurityException {
        // Use it to build an X509 trust manager.
        KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(
                KeyManagerFactory.getDefaultAlgorithm());
        keyManagerFactory.init(keyStore, PASSWORD.toCharArray());
        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(
                TrustManagerFactory.getDefaultAlgorithm());
        trustManagerFactory.init(keyStore);
        TrustManager[] trustManagers = trustManagerFactory.getTrustManagers();
        if (trustManagers.length != 1 || !(trustManagers[0] instanceof X509TrustManager)) {
            throw new IllegalStateException("Unexpected default trust managers:"
                    + Arrays.toString(trustManagers));
        }
        return trustManagers;
    }
    
   /**
     * Returns keystore read from raw folder
     * @return read keystore
     * @throws KeyStoreException if something goes wrong with reading
     * @throws CertificateException if something goes wrong with loading
     * @throws NoSuchAlgorithmException if something goes wrong with loading
     * @throws IOException if something goes wrong with loading
     */
    private KeyStore readKeyStore() throws KeyStoreException, CertificateException, NoSuchAlgorithmException, IOException {

        KeyStore ks = KeyStore.getInstance("BKS");

        InputStream is = null;
        try {
            is = context.getResources().openRawResource(R.raw.keystore);
            ks.load(is, PASSWORD.toCharArray());
        } finally {
            if (is != null) {
                is.close();
            }
        }
        return ks;
     }