import org.apache.http.client.methods.CloseableHttpResponse; //导入方法依赖的package包/类

/**

* Makes a HTTP request to the given URL using the given request body,

* parameters and HTTP headers. The parameters are used as URL parameters,

* but if there's a parameter "resourceId", it's added directly to the end

* of the URL. If there's no request body, the value can be null.

*

* @param url URL where the request is sent

* @param params request parameters

* @param requestBody request body

* @param headers HTTP headers to be added to the request

* @return response as string

*/

@Override

public ClientResponse send(String url, String requestBody, Map params, Map headers) {

// Build target URL

url = ClientUtil.buildTargetURL(url, params);

// Create HTTP client

CloseableHttpClient httpClient = HttpClients.createDefault();

// Build request

HttpUriRequest request = this.buildtHttpRequest(url, requestBody, headers);

LOGGER.info("Starting HTTP {} operation.", request.getMethod());

// Add headers

if (headers != null && !headers.isEmpty()) {

for (Map.Entry entry : headers.entrySet()) {

LOGGER.debug("Add header : \"{}\" = \"{}\"", entry.getKey(), entry.getValue());

request.setHeader(entry.getKey(), entry.getValue());

}

}

try {

//Send the request; It will immediately return the response in HttpResponse object

CloseableHttpResponse response = httpClient.execute(request);

// Get Content-Type header

Header[] contentTypeHeader = response.getHeaders("Content-Type");

String contentType = null;

// Check for null and empty

if (contentTypeHeader != null && contentTypeHeader.length > 0) {

contentType = contentTypeHeader[0].getValue();

}

// Get Status Code

int statusCode = response.getStatusLine().getStatusCode();

// Get reason phrase

String reasonPhrase = response.getStatusLine().getReasonPhrase();

// Get response payload

String responseStr = ClientUtil.getResponseString(response.getEntity());

response.close();

httpClient.close();

LOGGER.debug("REST response content type: \"{}\".", contentType);

LOGGER.debug("REST response status code: \"{}\".", statusCode);

LOGGER.debug("REST response reason phrase: \"{}\".", reasonPhrase);

LOGGER.debug("REST response : \"{}\".", responseStr);

LOGGER.info("HTTP {} operation completed.", request.getMethod());

return new ClientResponse(responseStr, contentType, statusCode, reasonPhrase);

} catch (IOException e) {

LOGGER.error(e.getMessage(), e);

LOGGER.warn("HTTP {} operation failed. An empty string is returned.", request.getMethod());

return null;

}

}