public static void createKeyStore(String filename, String password, String keyPassword,
    String alias, Key privateKey, Certificate cert) throws GeneralSecurityException, IOException {
    createKeyStore(filename, password, keyPassword, alias, privateKey, cert, "JKS");
  }
Creates a keystore with a single key and saves it to a file. This method will always generate a
keystore file in JKS format.
@param filename    String file to save
@param password    String store password to set on keystore
@param keyPassword String key password to set on key
@param alias       String alias to use for the key
@param privateKey  Key to save in keystore
@param cert        Certificate to use as certificate chain associated to key
@throws GeneralSecurityException for any error with the security APIs
@throws IOException              if there is an I/O error saving the file
hbase-http/src/test/java/org/apache/hadoop/hbase/http/ssl/KeyStoreTestUtil.java