httpclient模拟post请求json封装表单数据的实现方法_Java教程

httpclient模拟post请求json封装表单数据的实现方法

2020-07-21 11:30java教程网 Java教程

下面小编就为大家带来一篇httpclient模拟post请求json封装表单数据的实现方法。小编觉得挺不错的，现在就分享给大家，也给大家做个参考。一起跟随小编过来看看吧

废话不说上代码：

									public static String httpPostWithJSON(String url) throws Exception {

									    HttpPost httpPost = new HttpPost(url);

									    CloseableHttpClient client = HttpClients.createDefault();

									    String respContent = null;

									//    json方式

									    JSONObject jsonParam = new JSONObject(); 

									    jsonParam.put("name", "admin");

									    jsonParam.put("pass", "123456");

									    StringEntity entity = new StringEntity(jsonParam.toString(),"utf-8");//解决中文乱码问题  

									    entity.setContentEncoding("UTF-8");  

									    entity.setContentType("application/json");  

									    httpPost.setEntity(entity);

									    System.out.println();

									//    表单方式

									//    List<BasicNameValuePair> pairList = new ArrayList<BasicNameValuePair>(); 

									//    pairList.add(new BasicNameValuePair("name", "admin"));

									//    pairList.add(new BasicNameValuePair("pass", "123456"));

									//    httpPost.setEntity(new UrlEncodedFormEntity(pairList, "utf-8"));  

									    HttpResponse resp = client.execute(httpPost);

									    if(resp.getStatusLine().getStatusCode() == 200) {

									      HttpEntity he = resp.getEntity();

									      respContent = EntityUtils.toString(he,"UTF-8");

									    }

									    return respContent;

									  }

									  public static void main(String[] args) throws Exception {

									    String result = httpPostWithJSON("http://localhost:8080/hcTest2/Hc");

									    System.out.println(result);

									  }

post方式就要考虑提交的表单内容怎么传输了。本文name和pass就是表单的值了。

封装表单属性可以用json也可以用传统的表单，如果是传统表单的话要注意，也就是在上边代码注释那部分。用这种方式的话在servlet里也就是数据处理层可以通过request.getParameter(”string“)直接获取到属性值。就是相比json这种要简单一点，不过在实际开发中一般都是用json做数据传输的。用json的话有两种选择一个是阿里巴巴的fastjson还有一个就是谷歌的gson。fastjson相比效率比较高，gson适合解析有规律的json数据。博主这里用的是fastjson。还有用json的话在数据处理层要用流来读取表单属性，这就是相比传统表单多的一点内容。代码下边已经有了。

									public class HcServlet extends HttpServlet {

									  private static final long serialVersionUID = 1L;

									  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

									    doPost(request, response);

									  }

									  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

									    request.setCharacterEncoding("UTF-8"); 

									    response.setContentType("text/html;charset=UTF-8"); 

									    String acceptjson = ""; 

									    User user = new User();

									    BufferedReader br = new BufferedReader(new InputStreamReader( 

									        (ServletInputStream) request.getInputStream(), "utf-8")); 

									    StringBuffer sb = new StringBuffer(""); 

									    String temp; 

									    while ((temp = br.readLine()) != null) { 

									      sb.append(temp); 

									    } 

									    br.close(); 

									    acceptjson = sb.toString(); 

									    if (acceptjson != "") { 

									      JSONObject jo = JSONObject.parseObject(acceptjson);

									      user.setUsername(jo.getString("name"));

									      user.setPassword(jo.getString("pass"));

									    } 

									    request.setAttribute("user", user);

									    request.getRequestDispatcher("/message.jsp").forward(request, response);

									  }

									}