基于 HttpClient 4.5 的 HttpClientUtils

---

我编写工具类所参考的文档

pache HttpClient：

http://hc.apache.org/httpcomponents-client-ga/index.html

中文翻译教程：

https://www.yiibai.com/apache_httpclient

stackoverflow 关于SSL的讨论：

https://stackoverflow.com/questions/19517538/ignoring-ssl-certificate-in-apache-httpclient-4-3

代码要点

1、基于httpclient 4.5.8，代码无deprecated

2、GET请求 + POST请求

3、ResponseHandler处理响应，自动释放所有HTTP连接

4、忽略验证SSL证书来处理Https请求

5、请求携带CookieStore

参考代码（java）

public class HttpClientUtils {

    private static final Logger log = LoggerFactory.getLogger(HttpClientUtils.class);

    /**
     * POST 请求
     *
     * @param uri URI
     * @return response
     * @throws IOException
     */
    public static String doPost(String uri) throws IOException {
        CloseableHttpClient httpClient = createHttpClient("", true, 10);
        //创建post方式请求对象
        HttpPost httpPost = new HttpPost(uri);
        httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
        httpPost.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 6.1; rv:6.0.2) Gecko/20100101 Firefox/6.0.2");

        ResponseHandler<String> responseHandler = new ResponseHandler<String>() {
            @Override
            public String handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
                int status = response.getStatusLine().getStatusCode();
                if (status >= 200 && status < 300) {
                    HttpEntity entity = response.getEntity();
                    return entity != null ? EntityUtils.toString(entity, "UTF-8") : null;
                } else {
                    log.error("Unexpected response status: " + status);
                    throw new ClientProtocolException("Unexpected response status: " + status);
                }
            }
        };
        String response = httpClient.execute(httpPost, responseHandler);
        return response;
    }

    /**
     * Get 请求
     *
     * @param uri URI
     * @return response
     * @throws IOException
     */
    public static String doGet(String uri) throws IOException {
        CloseableHttpClient httpClient = createHttpClient("", true, 10);
        HttpGet httpGet = new HttpGet(uri);
        httpGet.setHeader("Content-type", "application/x-www-form-urlencoded");
        httpGet.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 6.1; rv:6.0.2) Gecko/20100101 Firefox/6.0.2");

        ResponseHandler<String> responseHandler = new ResponseHandler<String>() {
            @Override
            public String handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
                int status = response.getStatusLine().getStatusCode();
                if (status >= 200 && status < 300) {
                    HttpEntity entity = response.getEntity();
                    return entity != null ? EntityUtils.toString(entity, "UTF-8") : null;
                } else {
                    log.error("Unexpected response status: " + status);
                    throw new ClientProtocolException("Unexpected response status: " + status);
                }
            }
        };
        String response = httpClient.execute(httpGet, responseHandler);
        return response;
    }

    /**
     * @param sessionId         会话ID
     * @param automaticRedirect 自动重定向
     * @param timeOut           超时时间
     * @return CloseableHttpClient
     */
    private static CloseableHttpClient createHttpClient(String sessionId, boolean automaticRedirect, int timeOut) {
        //忽略校验HTTPS服务器证书, 将hostname校验和CA证书校验同时关闭
        SSLContext sslContext = null;
        try {
            sslContext = SSLContexts.custom()
                    .loadTrustMaterial(TrustSelfSignedStrategy.INSTANCE)
                    .build();
        } catch (NoSuchAlgorithmException | KeyManagementException | KeyStoreException e) {
            log.error("HttpClientUtils.createHttpClient: " + e);
        }
        //设置http和https协议对应的处理socket链接工厂的对象
        Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("http", PlainConnectionSocketFactory.INSTANCE)
                .register("https", new SSLConnectionSocketFactory(sslContext, NoopHostnameVerifier.INSTANCE))
                .build();
        PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager(registry);
        //构建请求配置信息
        timeOut = timeOut * 1000;
        RequestConfig requestConfig = RequestConfig.custom()
                .setSocketTimeout(timeOut) //获取数据的超时时间
                .setConnectTimeout(timeOut) //建立连接的超时时间
                .setConnectionRequestTimeout(timeOut) //连接池获取到连接的超时时间
                .build();
        //创建自定义httpclient对象
        HttpClientBuilder builder = HttpClients.custom();
        builder.setDefaultRequestConfig(requestConfig); //设置默认请求配置
        builder.setConnectionManager(connectionManager); //设置连接管理器
        if (!automaticRedirect) { //设置自动重定向配置
            builder.disableRedirectHandling();
        }
        //配置CookieStore
        CookieStore cookieStore = null;
        if (StringUtils.isNotBlank(sessionId)) {
             //TODO...redis查找cookieStore
            if (cookieStore == null) {
                cookieStore = new BasicCookieStore();
            }
            builder.setDefaultCookieStore(cookieStore);
        }
        CloseableHttpClient httpClient = builder.build();
        return httpClient;
    }
}