模板
教程
環境
性能
功能
管理
HttpComponents組件特性探究(7)
return result;
}
/**
* @param uri
* @param nameValuePairs
* @return
*/
public static PostMethod createPostMethod(String uri, NameValuePair[] nameValuePairs) {
PostMethod method = new PostMethod(uri);
method.addParameters(nameValuePairs);
method.getParams().setContentCharset(charsetName);
return method;
}
/**
* @param uri
* @param nameValuePairs
* @return
*/
public static GetMethod createGetMethod(String uri, NameValuePair[] nameValuePairs) {
GetMethod method = new GetMethod(uri);
List list = Lists.newArrayList();
if (nameValuePairs != null) {
Collections.addAll(list, nameValuePairs);
method.setQueryString(list.toArray(new NameValuePair[nameValuePairs.length]));
}
method.getParams().setContentCharset(charsetName);
return method;
}
public static HttpClient createHttpClient() {
//1.
HttpClient httpClient = new HttpClient(new MultiThreadedHttpConnectionManager());
//2.
HttpConnectionManagerParams httpConnectionManagerParams = httpClient
.getHttpConnectionManager().getParams();
httpConnectionManagerParams.setConnectionTimeout(connectionTimeout);
httpConnectionManagerParams.setTcpNoDelay(true);//Nagle's algorithm
httpConnectionManagerParams.setSoTimeout(timeOut);
httpConnectionManagerParams.setDefaultMaxConnectionsPerHost(maxHostConnections);
httpConnectionManagerParams.setMaxTotalConnections(maxTotalConnections);
//3.
HttpClientParams httpClientParam = httpClient.getParams();
//httpClientParam.setConnectionManagerTimeout(connectionTimeout);//暫且不關注這個超時設置,后面根據性能酌情考慮
httpClientParam.setParameter(HttpMethodParams.RETRY_HANDLER,
new DefaultHttpMethodRetryHandler(retryCount, false));
httpClientParam.setCookiePolicy(CookiePolicy.BROWSER_COMPATIBILITY);
return httpClient;
}
public static JSONObject doGet(String url, NameValuePair[] params) {
return executeMethod(createHttpClient(), createGetMethod(url, params));
}
public static JSONObject doPost(String url, NameValuePair[] params) {
return executeMethod(createHttpClient(), createPostMethod(url, params));
}
protected HttpClientUtils() {
}
public void setTimeOut(int timeOut) {
HttpClientUtils.timeOut = timeOut;
}
public static int getTimeOut() {
return timeOut;
}
public static int getRetryCount() {
return retryCount;
}
public void setRetryCount(int retryCount) {
HttpClientUtils.retryCount = retryCount;
}
public static int getConnectionTimeout() {
return connectionTimeout;
}
public void setConnectionTimeout(int connectionTimeout) {
HttpClientUtils.connectionTimeout = connectionTimeout;
}
public static int getMaxHostConnections() {
return maxHostConnections;
}
public void setMaxHostConnections(int maxHostConnections) {
HttpClientUtils.maxHostConnections = maxHostConnections;
}
public static int getMaxTotalConnections() {
return maxTotalConnections;
}
public void setMaxTotalConnections(int maxTotalConnections) {
HttpClientUtils.maxTotalConnections = maxTotalConnections;
}
public static String getCharsetName() {
return charsetName;
}
public void setCharsetName(String charsetName) {
HttpClientUtils.charsetName = charsetName;
}
}
好了，有了活生生的代碼，我們來總結一下httpClient封裝過程中需要注意的一些事項吧。恩，其實更多的是體現在安全，性能上面：
(1)多線程模型，尤其注意finally中collection的釋放問題。除此之外，需要考慮池化連接的異常處理，這是我文中提到特別注意的三大異常之一;
(2)Retry機制中對冪等性的處理。尤其是在httpClient4中，put和post操作，未按照http規范行事，需要我們額外注意;
(3)SSL、TLS的定制化處理;
(4)并發標記的處理，這里使用了Concurrency in practice中的并發annotation，有什么用?感興趣的朋友可以了解下SureLogic(http://www.surelogic.com/concurrency-tools.html)，別問我要license，因為俺也不是apache開源社區的developer呀;
(5)攔截器對header的處理;
