HttpClient调用外部项目接口工具类示例

简介：
本工具类提供通过HttpClient访问外部系统API的功能示例，包括GET和POST请求方法，适用于Java项目的集成开发。 HttpClient是Apache Jakarta Commons子项目中的一个开源Http客户端实现工具库，支持HTTP1.1和2.0协议，并提供发送请求及接收响应的功能。 使用HttpClient的优点包括简化了Http请求的处理流程、提供了更好的性能与可靠性。它也支持HTTPS加密连接以及Cookies、Session和Authentication等功能。 下面是一个示例代码展示如何利用HttpClient来实现调用外部项目接口工具类： 首先，需要引入相关的依赖项： ```java import org.apache.http.NameValuePair; import org.apache.http.HttpEntity; import org.apache.http.client.config.RequestConfig; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpPost; import org.apache.http.conn.ssl.DefaultHostnameVerifier; import org.apache.http.conn.util.PublicSuffixMatcher; import org.apache.http.conn.util.PublicSuffixMatcherLoader; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClients; import org.apache.http.message.BasicNameValuePair; import org.apache.http.util.EntityUtils; ``` 然后，可以创建一个名为HttpUtils的工具类来发送HttpGet和HttpPost请求： ```java public class HttpUtils { private static RequestConfig requestConfig = RequestConfig.custom() .setSocketTimeout(15000) .setConnectTimeout(15000) .setConnectionRequestTimeout(15000) .build(); public static String sendHttpGet(HttpGet httpGet) { CloseableHttpClient httpClient = null; CloseableHttpResponse response = null; HttpEntity entity = null; String responseContent = null; try { httpClient = HttpClients.createDefault(); httpGet.setConfig(requestConfig); response = httpClient.execute(httpGet); entity = response.getEntity(); if (entity != null) { responseContent = EntityUtils.toString(entity, UTF-8); } } catch (Exception e) { e.printStackTrace(); } finally { try { if (response != null) response.close(); if (httpClient != null) httpClient.close(); } catch (IOException ioe) { ioe.printStackTrace(); } } return responseContent; } public static String sendHttpPost(String httpUrl, Map maps) { HttpPost httpPost = new HttpPost(httpUrl); List params = new ArrayList<>(); for (Map.Entry entry : maps.entrySet()) { params.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } try { UrlEncodedFormEntity entity = new UrlEncodedFormEntity(params, UTF-8); httpPost.setEntity(entity); CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = httpClient.execute(httpPost); HttpEntity responseEntity = response.getEntity(); String responseContent = EntityUtils.toString(responseEntity, UTF-8); return responseContent; } catch (Exception e) { e.printStackTrace(); } return null; } } ``` 在上述示例中，我们创建了一个名为HttpUtils的工具类，并提供了两个方法：`sendHttpGet()` 和 `sendHttpPost()`。前者用于发送GET请求，后者用于提交POST数据。 使用HttpClient时需要注意以下几点： - 正确配置超时时间等参数； - 确保关闭连接以释放资源； - 适当处理可能出现的各种异常情况。 通过合理运用和设置这些特性，可以确保HttpClient的高效与稳定。