javaWeb发送Post请求的两种方式(form,json)

客官°小女子只卖身不卖艺 2022-01-29 01:13 877阅读 0赞

前提:通过HttpClient实现.

方式一:以form表单形式提交数据

jar包:

commons-logging-1.1.1.jar

httpclient-4.5.jar

httpcore-4.4.1.jar

代码实现:

客户端(此时的后台)如何发送请求:

导入:

import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    import org.apache.http.HttpResponse;
    import org.apache.http.HttpStatus;
    import org.apache.http.client.entity.UrlEncodedFormEntity;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.impl.client.CloseableHttpClient;
    import org.apache.http.impl.client.HttpClientBuilder;
    import org.apache.http.message.BasicNameValuePair;
    import org.apache.http.util.EntityUtils;

方法:

/**
     * 以form表单形式提交数据，发送post请求
     * @explain 
     *   1.请求头：httppost.setHeader("Content-Type","application/x-www-form-urlencoded")
     *   2.提交的数据格式：key1=value1&key2=value2...
     * @param url 请求地址
     * @param paramsMap 具体数据
     * @return 服务器返回数据
     */
    public static String httpPostWithForm(String url,Map<String, String> paramsMap){
        // 用于接收返回的结果
        String resultData ="";
         try {
                HttpPost post = new HttpPost(url);
                List<BasicNameValuePair> pairList = new ArrayList<BasicNameValuePair>();
                // 迭代Map-->取出key,value放到BasicNameValuePair对象中-->添加到list中
                for (String key : paramsMap.keySet()) {
                    pairList.add(new BasicNameValuePair(key, paramsMap.get(key)));
                }
                UrlEncodedFormEntity uefe = new UrlEncodedFormEntity(pairList, "utf-8");
                post.setEntity(uefe); 
                // 创建一个http客户端
                CloseableHttpClient httpClient = HttpClientBuilder.create().build();
                // 发送post请求
                HttpResponse response = httpClient.execute(post);
                
                // 状态码为：200
                if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
                    // 返回数据：
                    resultData = EntityUtils.toString(response.getEntity(),"UTF-8");
                }else{
                    throw new RuntimeException("接口连接失败！");
                }
            } catch (Exception e) {
                throw new RuntimeException("接口连接失败！");
            }
         return resultData;
    }

服务器端如何接收客户端传递的数据?

request.getParameter("key");

客户端调用测试:

public static void main(String[] args) {
        String requestUrl = "http://localhost:8070/test/rz/server/rzxx/at_VaildToken.do";
        Map<String, String> paramsMap = new HashMap<String, String>(1);
        paramsMap.put("un_value", "B022420184794C7C9D5096CC5F3AE7D2");
        // 发送post请求并接收返回结果
        String resultData = httpPostWithForm(requestUrl, paramsMap);
        System.out.println(resultData);
    }

方式2:以JSONObject形式提交数据

见:[https://www.cnblogs.com/Marydon20170307/p/9202987.html][https_www.cnblogs.com_Marydon20170307_p_9202987.html]

更多资料参考上续链接.

[https_www.cnblogs.com_Marydon20170307_p_9202987.html]: https://www.cnblogs.com/Marydon20170307/p/9202987.html