Apache HttpClient - Http Post 请求
POST请求用于向服务器发送数据；例如客户信息、文件上传等，使用HTML表单。
HttpClient API 提供了一个名为HttpPost的类，它表示 POST 请求。
按照下面给出的步骤使用 HttpClient 库发送 HTTP POST 请求。
第 1 步 - 创建 HttpClient 对象
HttpClients类的createDefault ()方法返回CloseableHttpClient类的对象，该类是HttpClient接口的基本实现。
使用此方法创建一个 HttpClient 对象。
CloseableHttpClient httpClient = HttpClients.createDefault();
第 2 步 - 创建 HttpPost 对象
HttpPost类表示HTTP POST请求。这会发送所需的数据并使用 URI 检索给定服务器的信息。
通过实例化HttpPost类来创建此请求，并将表示 URI 的字符串值作为参数传递给其构造函数。
HttpGet httpGet = new HttpGet("https://www.tutorialspoint.com/");
第 3 步 - 执行获取请求
CloseableHttpClient 对象的execute ()方法接受HttpUriRequest（接口）对象（即HttpGet、HttpPost、HttpPut、HttpHead 等）并返回响应对象。
HttpResponse httpResponse = httpclient.execute(httpget);
例子
以下示例演示了使用 HttpClient 库执行 HTTP POST 请求。
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
public class HttpPostExample {
public static void main(String args[]) throws Exception{
//Creating a HttpClient object
CloseableHttpClient httpclient = HttpClients.createDefault();
//Creating a HttpGet object
HttpPost httppost = new HttpPost("https://www.tutorialspoint.com/");
//Printing the method used
System.out.println("Request Type: "+httppost.getMethod());
//Executing the Get request
HttpResponse httpresponse = httpclient.execute(httppost);
Scanner sc = new Scanner(httpresponse.getEntity().getContent());
//Printing the status line
System.out.println(httpresponse.getStatusLine());
while(sc.hasNext()) {
System.out.println(sc.nextLine());
}
}
}
输出
上述程序生成以下输出。
Request Type: POST <!DOCTYPE html> <!--[if IE 8]><html class = "ie ie8"> <![endif]--> <!--[if IE 9]><html class = "ie ie9"> <![endif]--> <!--[if gt IE 9]><!--> <html lang = "en-US"> <!--<![endif]--> <head> <!-- Basic --> <meta charset = "utf-8"> <title>Parallax Scrolling, Java Cryptography, YAML, Python Data Science, Java i18n, GitLab, TestRail, VersionOne, DBUtils, Common CLI, Seaborn, Ansible, LOLCODE, Current Affairs 2018, Apache Commons Collections</title> <meta name = "Description" content = "Parallax Scrolling, Java Cryptography, YAML, Python Data Science, Java i18n, GitLab, TestRail, VersionOne, DBUtils, Common CLI, Seaborn, Ansible, LOLCODE, Current Affairs 2018, Intellij Idea, Apache Commons Collections, Java 9, GSON, TestLink, Inter Process Communication (IPC), Logo, PySpark, Google Tag Manager, Free IFSC Code, SAP Workflow"/> <meta name = "Keywords" content="Python Data Science, Java i18n, GitLab, TestRail, VersionOne, DBUtils, Common CLI, Seaborn, Ansible, LOLCODE, Gson, TestLink, Inter Process Communication (IPC), Logo"/> <meta http-equiv = "X-UA-Compatible" content = "IE = edge"> <meta name = "viewport" conten t= "width = device-width,initial-scale = 1.0,userscalable = yes"> <link href = "https://cdn.muicss.com/mui-0.9.39/extra/mui-rem.min.css" rel = "stylesheet" type = "text/css" /> <link rel = "stylesheet" href = "/questions/css/home.css?v = 3" /> <script src = "/questions/js/jquery.min.js"></script> <script src = "/questions/js/fontawesome.js"></script> <script src = "https://cdn.muicss.com/mui-0.9.39/js/mui.min.js"></script> </head> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . </script> </body> </html>