@Override
public HttpClient create() {
  HttpClient client = new HttpClient();
  if (soTimeout >= 0) {
    client.getParams().setSoTimeout(soTimeout);
  }

  ClassAliasResolver<HttpMethodRetryHandler> aliasResolver = new ClassAliasResolver<>(HttpMethodRetryHandler.class);
  HttpMethodRetryHandler httpMethodRetryHandler;
  try {
    httpMethodRetryHandler = GobblinConstructorUtils.invokeLongestConstructor(aliasResolver.resolveClass(httpMethodRetryHandlerClass), httpMethodRetryCount, httpRequestSentRetryEnabled);
  } catch (ReflectiveOperationException e) {
    throw new RuntimeException(e);
  }
  client.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, httpMethodRetryHandler);

  if (connTimeout >= 0) {
    client.getHttpConnectionManager().getParams().setConnectionTimeout(connTimeout);
  }

  return client;
}
 

private HttpMethodRetryHandler createRetryTwiceHandler() {
    return new HttpMethodRetryHandler() {
        @Override
        public boolean retryMethod(final HttpMethod method, final IOException exception, int executionCount) {
            if (executionCount >= 2) {
                // Do not retry if over max retry count
                return false;
            }
            if (exception instanceof NoHttpResponseException) {
                // Retry if the server dropped connection on us
                return true;
            }
            if (!method.isRequestSent()) {
                // Retry if the request has not been sent fully or
                // if it's OK to retry methods that have been sent
                return true;
            }
            // otherwise do not retry
            return false;
        }
    };
}
 

protected HttpMethodRetryHandler createRetryTwiceHandler() {
    return new HttpMethodRetryHandler() {
        @Override
        public boolean retryMethod(final HttpMethod method, final IOException exception, int executionCount) {
            if (executionCount >= 2) {
                // Do not retry if over max retry count
                return false;
            }
            if (exception instanceof NoHttpResponseException) {
                // Retry if the server dropped connection on us
                return true;
            }
            if (!method.isRequestSent()) {
                // Retry if the request has not been sent fully or
                // if it's OK to retry methods that have been sent
                return true;
            }
            // otherwise do not retry
            return false;
        }
    };
}
 

/**
 * @return A HttpMethodRetryHandler with given number of retries.
 */
public static HttpMethodRetryHandler getHttpMethodRetryHandler(final int retryCount) {

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("Initializing new HttpMethodRetryHandler with retry count " + retryCount);
    }

    return new HttpMethodRetryHandler() {
        @Override
        public boolean retryMethod(final HttpMethod method, final IOException exception, final int executionCount) {
            if (executionCount >= retryCount) {
                // Do not retry if over max retry count
                return false;
            }
            if (exception instanceof NoHttpResponseException) {
                // Retry if the server dropped connection on us
                return true;
            }
            if (!method.isRequestSent()) {
                // Retry if the request has not been sent fully or
                // if it's OK to retry methods that have been sent
                return true;
            }
            // otherwise do not retry
            return false;
        }
    };
}
 

/**
 * @return A HttpMethodRetryHandler with given number of retries.
 */
public static HttpMethodRetryHandler getHttpMethodRetryHandler(final int retryCount) {

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("Initializing new HttpMethodRetryHandler with retry count " + retryCount);
    }

    return new HttpMethodRetryHandler() {
        @Override
        public boolean retryMethod(final HttpMethod method, final IOException exception, int executionCount) {
            if (executionCount >= retryCount) {
                // Do not retry if over max retry count
                return false;
            }
            if (exception instanceof NoHttpResponseException) {
                // Retry if the server dropped connection on us
                return true;
            }
            if (!method.isRequestSent()) {
                // Retry if the request has not been sent fully or
                // if it's OK to retry methods that have been sent
                return true;
            }
            // otherwise do not retry
            return false;
        }
    };
}
 

/**
 * Execute a request
 *
 * @param httpMethodProxyRequest
 * @param httpServletRequest
 * @param httpServletResponse
 * @param history
 * @throws Exception
 */
private void executeRequest(HttpMethod httpMethodProxyRequest,
                            HttpServletRequest httpServletRequest,
                            PluginResponse httpServletResponse,
                            History history) throws Exception {
    int intProxyResponseCode = 999;
    // Create a default HttpClient
    HttpClient httpClient = new HttpClient();
    HttpState state = new HttpState();

    try {
        httpMethodProxyRequest.setFollowRedirects(false);
        ArrayList<String> headersToRemove = getRemoveHeaders();

        httpClient.getParams().setSoTimeout(60000);

        httpServletRequest.setAttribute("com.groupon.odo.removeHeaders", headersToRemove);

        // exception handling for httpclient
        HttpMethodRetryHandler noretryhandler = new HttpMethodRetryHandler() {
            public boolean retryMethod(
                final HttpMethod method,
                final IOException exception,
                int executionCount) {
                return false;
            }
        };

        httpMethodProxyRequest.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, noretryhandler);

        intProxyResponseCode = httpClient.executeMethod(httpMethodProxyRequest.getHostConfiguration(), httpMethodProxyRequest, state);
    } catch (Exception e) {
        // Return a gateway timeout
        httpServletResponse.setStatus(504);
        httpServletResponse.setHeader(Constants.HEADER_STATUS, "504");
        httpServletResponse.flushBuffer();
        return;
    }
    logger.info("Response code: {}, {}", intProxyResponseCode,
                HttpUtilities.getURL(httpMethodProxyRequest.getURI().toString()));

    // Pass the response code back to the client
    httpServletResponse.setStatus(intProxyResponseCode);

    // Pass response headers back to the client
    Header[] headerArrayResponse = httpMethodProxyRequest.getResponseHeaders();
    for (Header header : headerArrayResponse) {
        // remove transfer-encoding header.  The http libraries will handle this encoding
        if (header.getName().toLowerCase().equals("transfer-encoding")) {
            continue;
        }

        httpServletResponse.setHeader(header.getName(), header.getValue());
    }

    // there is no data for a HTTP 304 or 204
    if (intProxyResponseCode != HttpServletResponse.SC_NOT_MODIFIED &&
        intProxyResponseCode != HttpServletResponse.SC_NO_CONTENT) {
        // Send the content to the client
        httpServletResponse.resetBuffer();
        httpServletResponse.getOutputStream().write(httpMethodProxyRequest.getResponseBody());
    }

    // copy cookies to servlet response
    for (Cookie cookie : state.getCookies()) {
        javax.servlet.http.Cookie servletCookie = new javax.servlet.http.Cookie(cookie.getName(), cookie.getValue());

        if (cookie.getPath() != null) {
            servletCookie.setPath(cookie.getPath());
        }

        if (cookie.getDomain() != null) {
            servletCookie.setDomain(cookie.getDomain());
        }

        // convert expiry date to max age
        if (cookie.getExpiryDate() != null) {
            servletCookie.setMaxAge((int) ((cookie.getExpiryDate().getTime() - System.currentTimeMillis()) / 1000));
        }

        servletCookie.setSecure(cookie.getSecure());

        servletCookie.setVersion(cookie.getVersion());

        if (cookie.getComment() != null) {
            servletCookie.setComment(cookie.getComment());
        }

        httpServletResponse.addCookie(servletCookie);
    }
}
 

public synchronized void setRetryHandler(final HttpMethodRetryHandler handler) {
    httpClientParams.setParameter(HttpMethodParams.RETRY_HANDLER, handler);
}