• Java的HTTPClient工具类（附代码实现）

    博文简介：       

            由于工作内容频繁对接第三方系统，用到HTTP协议进行数据传输。

            官方地址：Apache HttpComponents – Apache HttpComponents 

            组件版本：org.apache.httpcomponents:httpclient:4.5.2

            已支持集：SSL + 自定义参数 + Header  的配置 +  httpClinet配置代理

            已实现集：

                    1. GET 以URL参数编码发送

                    2. POST 以请求体JSON发送

                    3. POST 以表单的形式发送

            工具函数：（示例）

    1. public class HttpUtil {
    2.  
    3.     // GET URL编码指定字符集 ----------
    4.  
    5.     // url : 资源地址定位 ; param : url?后的参数 ; charSet : URL编码使用字符集,例如:UTF-8
    6.     public static String get(String url, Map urlParam, Map header, String charSet, boolean ssl) {
    7.         CloseableHttpClient httpClient = ssl ? getHttpClient() : HttpClients.createDefault();
    8.         HttpGet httpGet = new HttpGet(charSet == null ? addParams2Url(url, urlParam) : addParams2UrlWithCharSet(url, urlParam, charSet));
    9.         RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(6000 * 2).setConnectionRequestTimeout(6000 * 2).setSocketTimeout(6000 * 2).build();
    10.         httpGet.setConfig(requestConfig);
    11.  
    12.         try {
    13.             // send get request : 发送GET请求
    14.             httpGet.setHeaders(createHeader(header));
    15.             CloseableHttpResponse response = httpClient.execute(httpGet);
    16.             int statusCode = response.getStatusLine().getStatusCode();
    17.             if (statusCode != 200) return null;
    18.  
    19.             // do something useful with response body : 业务逻辑
    20.  
    21.             HttpEntity entity = response.getEntity();
    22.             String res = EntityUtils.toString(entity, "UTF-8");
    23.             EntityUtils.consume(entity);
    24.             return res;
    25.         } catch (Exception e) {
    26.  
    27.         } finally {
    28.             try {
    29.                 httpClient.close();
    30.             } catch (IOException e) {
    31.  
    32.             }
    33.         }
    34.         return null;
    35.     }
    36.  
    37.     private static String addParams2Url(String url, Map params) {
    38.         return addParams2UrlWithCharSet(url, params, null);
    39.     }
    40.  
    41.     private static String addParams2UrlWithCharSet(String url, Map params, String charSet) {
    42.         if (params == null || params.isEmpty()) {
    43.             return url;
    44.         }
    45.         StringBuilder sb = new StringBuilder();
    46.         try {
    47.             for (Map.Entry entry : params.entrySet()) {
    48.                 sb.append("&").append(entry.getKey()).append("=");
    49.                 sb.append(charSet == null ? entry.getValue() : URLEncoder.encode(entry.getValue(), charSet));
    50.             }
    51.             if (!url.contains("?")) {
    52.                 sb.deleteCharAt(0).insert(0, "?");
    53.             }
    54.         } catch (Exception e) {
    55.  
    56.         }
    57.         return url + sb;
    58.     }
    59.  
    60.     // POST 以请求体JSON发送数据--------------------
    61.  
    62.     public static String postJson(String url, Map urlParam, Map header, String data, boolean ssl) {
    63.         CloseableHttpClient httpClient = ssl ? getHttpClient() : HttpClients.createDefault();
    64.         HttpPost httpPost = new HttpPost(addParams2Url(url, urlParam));
    65.         RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(6000 * 2).setConnectionRequestTimeout(6000 * 2).setSocketTimeout(6000 * 2).build();
    66.         httpPost.setConfig(requestConfig);
    67.  
    68.         try {
    69.             httpPost.setHeaders(createHeader(header));
    70.             httpPost.setEntity(new StringEntity(data, ContentType.APPLICATION_JSON));
    71.             CloseableHttpResponse response = httpClient.execute(httpPost);
    72.             int statusCode = response.getStatusLine().getStatusCode();
    73.             if (statusCode != 200) return null;
    74.  
    75.             HttpEntity entity = response.getEntity();
    76.             String res = EntityUtils.toString(entity, "UTF-8");
    77.             EntityUtils.consume(entity);
    78.             response.close();
    79.             return res;
    80.         } catch (Exception e) {
    81.  
    82.         } finally {
    83.             try {
    84.                 httpClient.close();
    85.             } catch (Exception e) {
    86.  
    87.             }
    88.         }
    89.         return null;
    90.     }
    91.  
    92.     // POST 以表单的形式发送数据-----------
    93.  
    94.     public static String postForm(String url, Map urlParam, Map header, Map data, boolean ssl) {
    95.         CloseableHttpClient httpClient = ssl ? getHttpClient() : HttpClients.createDefault();
    96.         HttpPost httpPost = new HttpPost(addParams2Url(url, urlParam));
    97.         RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(6000 * 2).setConnectionRequestTimeout(6000 * 2).setSocketTimeout(6000 * 2).build();
    98.         httpPost.setConfig(requestConfig);
    99.  
    100.         try {
    101.             // config header content-type is application/x-www-form-urlencoded : 配置HTTP的Header:content-type
    102.             header = header != null ? header : new HashMap<>();
    103.             ContentType APPLICATION_FORM_URLENCODED_UTF8 = ContentType.create("application/x-www-form-urlencoded", Consts.UTF_8);
    104.             header.put("Content-Type", APPLICATION_FORM_URLENCODED_UTF8.toString());
    105.             httpPost.setHeaders(createHeader(header));
    106.  
    107.             // add key-value pair to entity : 设置参数到请求体中
    108.             List list = new ArrayList<>();
    109.             for (Map.Entry entry : data.entrySet()) {
    110.                 list.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
    111.             }
    112.             if (list.size() > 0) {
    113.                 UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, "UTF-8");
    114.                 httpPost.setEntity(entity);
    115.             }
    116.  
    117.             CloseableHttpResponse response = httpClient.execute(httpPost);
    118.             int statusCode = response.getStatusLine().getStatusCode();
    119.             if (statusCode != 200) return null;
    120.  
    121.             HttpEntity entity = response.getEntity();
    122.             String res = EntityUtils.toString(entity, "UTF-8");
    123.             EntityUtils.consume(entity);
    124.             response.close();
    125.             return res;
    126.         } catch (Exception e) {
    127.  
    128.         } finally {
    129.             try {
    130.                 httpClient.close();
    131.             } catch (Exception e) {
    132.  
    133.             }
    134.         }
    135.         return null;
    136.     }
    137.  
    138.     // HTTPS client 创建 --------------------
    139.  
    140.     public static CloseableHttpClient getHttpClient() {
    141.         X509TrustManager trustManager = new X509TrustManager() {
    142.             @Override
    143.             public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
    144.  
    145.             }
    146.  
    147.             @Override
    148.             public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
    149.  
    150.             }
    151.  
    152.             @Override
    153.             public X509Certificate[] getAcceptedIssuers() {
    154.                 return null;
    155.             }
    156.         };
    157.         SSLContext context = null;
    158.         try {
    159.             context = SSLContext.getInstance("SSL");
    160.             context.init(null, new TrustManager[]{trustManager}, null);
    161.             return HttpClients.custom().setSSLSocketFactory(new SSLConnectionSocketFactory(context)).build();
    162.         } catch (Exception e) {
    163.  
    164.         }
    165.         return null;
    166.     }
    167.  
    168.     // 批量创建请求头 --------------------
    169.  
    170.     private static Header[] createHeader(Map header) {
    171.         if (header == null || header.isEmpty()) return null;
    172.         List
       headers = new ArrayList<>();
    173.         for (String key : header.keySet()) {
    174.             headers.add(new BasicHeader(key, header.get(key)));
    175.         }
    176.         return headers.toArray(new Header[]{});
    177.     }
    178.  
    179. }

            配置代理（示例）：

    1. public class ClientExecuteProxy {
    2.  
    3.     public static void main(String[] args)throws Exception {
    4.         CloseableHttpClient httpclient = HttpClients.createDefault();
    5.         try {
    6.             HttpHost target = new HttpHost("httpbin.org", 443, "https");
    7.             HttpHost proxy = new HttpHost("127.0.0.1", 8080, "http");
    8.  
    9.             RequestConfig config = RequestConfig.custom()
    10.                     .setProxy(proxy)
    11.                     .build();
    12.             HttpGet request = new HttpGet("/");
    13.             request.setConfig(config);
    14.  
    15.             System.out.println("Executing request " + request.getRequestLine() + " to " + target + " via " + proxy);
    16.  
    17.             CloseableHttpResponse response = httpclient.execute(target, request);
    18.             try {
    19.                 System.out.println("----------------------------------------");
    20.                 System.out.println(response.getStatusLine());
    21.                 System.out.println(EntityUtils.toString(response.getEntity()));
    22.             } finally {
    23.                 response.close();
    24.             }
    25.         } finally {
    26.             httpclient.close();
    27.         }
    28.     }
    29.  
    30. }
    1. public class ClientProxyAuthentication {
    2.  
    3.     public static void main(String[] args) throws Exception {
    4.         CredentialsProvider credsProvider = new BasicCredentialsProvider();
    5.         credsProvider.setCredentials(
    6.                 new AuthScope("localhost", 8888),
    7.                 new UsernamePasswordCredentials("squid", "squid"));
    8.         credsProvider.setCredentials(
    9.                 new AuthScope("httpbin.org", 80),
    10.                 new UsernamePasswordCredentials("user", "passwd"));
    11.         CloseableHttpClient httpclient = HttpClients.custom()
    12.                 .setDefaultCredentialsProvider(credsProvider).build();
    13.         try {
    14.             HttpHost target = new HttpHost("httpbin.org", 80, "http");
    15.             HttpHost proxy = new HttpHost("localhost", 8888);
    16.  
    17.             RequestConfig config = RequestConfig.custom()
    18.                 .setProxy(proxy)
    19.                 .build();
    20.             HttpGet httpget = new HttpGet("/basic-auth/user/passwd");
    21.             httpget.setConfig(config);
    22.  
    23.             System.out.println("Executing request " + httpget.getRequestLine() + " to " + target + " via " + proxy);
    24.  
    25.             CloseableHttpResponse response = httpclient.execute(target, httpget);
    26.             try {
    27.                 System.out.println("----------------------------------------");
    28.                 System.out.println(response.getStatusLine());
    29.                 System.out.println(EntityUtils.toString(response.getEntity()));
    30.             } finally {
    31.                 response.close();
    32.             }
    33.         } finally {
    34.             httpclient.close();
    35.         }
    36.     }
    37. }

    参考地址：

    1. 官网示例：Apache HttpComponents – HttpClient Examples  

    2. 异步处理：Apache HttpComponents – HttpAsyncClient Quick Start  

    变更记录：

    2022-11-13 ： 初稿发布

    2022-12-26 ：简化实现类的封装，扩展 "配置代理" 及 "代理认证" 

    ** 希望得到你的参与和支持。 如果内容有描述不恰当的地方，请指出。 谢谢！**

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  • 原文地址：https://blog.csdn.net/qq_41107529/article/details/127827954