httpclient发送post请求

迈不过友情╰ 2023-10-08 20:16 54阅读 0赞

使用Apache HttpComponents提供的HttpClient发送POST请求可以分为以下几个步骤：

创建 HttpClient 对象

CloseableHttpClient httpClient = HttpClients.createDefault();

创建 HttpPost 对象并设置请求 URL

HttpPost httpPost = new HttpPost("http://www.example.com/submit-form");

设置 POST 请求的参数，可以使用UrlEncodedFormEntity对Form表单进行编码

List<NameValuePair> formParams = new ArrayList<>();
    formParams.add(new BasicNameValuePair("username", "user123"));
    formParams.add(new BasicNameValuePair("password", "pass123"));
    UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(formParams, Consts.UTF_8);
    httpPost.setEntity(urlEncodedFormEntity);

执行 HTTP POST 请求

CloseableHttpResponse httpResponse = httpClient.execute(httpPost);

处理结果

HttpEntity responseEntity = httpResponse.getEntity();
    if (responseEntity != null) {
        
        // 使用 EntityUtils 将响应实体转换为字符串
        String responseString = EntityUtils.toString(responseEntity);
        // 对响应结果进行处理
        System.out.println(responseString);
    }

关闭资源

httpResponse.close();
    httpClient.close();

完整示例代码：

import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.http.Consts;
    import org.apache.http.HttpEntity;
    import org.apache.http.NameValuePair;
    import org.apache.http.client.methods.CloseableHttpResponse;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.client.utils.URIBuilder;
    import org.apache.http.entity.StringEntity;
    import org.apache.http.message.BasicNameValuePair;
    import org.apache.http.impl.client.CloseableHttpClient;
    import org.apache.http.impl.client.HttpClients;
    import org.apache.http.client.entity.UrlEncodedFormEntity;
    import org.apache.http.util.EntityUtils;
    
    public class HttpClientExample {
        
    
        public static void main(String[] args) throws IOException {
        
            CloseableHttpClient httpClient = HttpClients.createDefault();
    
            try {
        
                HttpPost httpPost = new HttpPost("http://www.example.com/submit-form");
    
                List<NameValuePair> formParams = new ArrayList<>();
                formParams.add(new BasicNameValuePair("username", "user123"));
                formParams.add(new BasicNameValuePair("password", "pass123"));
    
                UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(formParams, Consts.UTF_8);
                httpPost.setEntity(urlEncodedFormEntity);
    
                CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
    
                try {
        
                    HttpEntity responseEntity = httpResponse.getEntity();
                    if (responseEntity != null) {
        
                        String responseString = EntityUtils.toString(responseEntity);
                        System.out.println(responseString);
                    }
                } finally {
        
                    httpResponse.close();
                }
            } finally {
        
                httpClient.close();
            }
        }
    }

以上是使用 HttpClient 发送 POST 请求的方式。需要注意的是，其它类型的 HTTP 方法同样可以通过 HttpClient 来实现，只需使用对应的 HttpGet、HttpPut、HttpDelete等类即可。