http请求

post/get请求工具类

• HttpRequest工具类

    package com.code.util;
    
    import java.io.*;
    import java.net.URL;
    import java.net.URLConnection;
    import java.util.List;
    import java.util.Map;
    
    public class HttpRequest {
        /**
         * 向指定URL发送GET方法的 请求
         *
         * @param url   发送请求的URL
         * @param param 请求参数，请求参数应该是name1=value1&name2=value2的形式。
         * @return URL所代表远程资源的响应
         */
        public static String sendGet(String url, String param) {
            String result = "";
            BufferedReader in = null;
            try {
                String urlName = url + "?" + param;
                URL realUrl = new URL(urlName);
                // 打开和URL之间的连接
                URLConnection conn = realUrl.openConnection();
                // 设置通用的请求属性
                conn.setRequestProperty("accept", "*/*");
                conn.setRequestProperty("connection", "Keep-Alive");
                conn.setRequestProperty("user-agent",
                        "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
                // 建立实际的连接
                conn.connect();
                // 获取所有响应头字段
                Map<String, List<String>> map = conn.getHeaderFields();
                // 遍历所有的响应头字段
                for (String key : map.keySet()) {
                    System.out.println(key + "--->" + map.get(key));
                }
                // 定义BufferedReader输入流来读取URL的响应
                in = new BufferedReader(
                        new InputStreamReader(conn.getInputStream(),"UTF-8"));
                String line;
                while ((line = in.readLine()) != null) {
                    result += line;
                }
            } catch (Exception e) {
                System.out.println("发送GET请求出现异常！" + e);
                e.printStackTrace();
            }
            // 使用finally块来关闭输入流
            finally {
                try {
                    if (in != null) {
                        in.close();
                    }
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
            return result;
        }
    
        /**
         * 向指定URL发送POST方法的请求
         *
         * @param url   发送请求的URL
         * @param param 请求参数，请求参数应该是name1=value1&name2=value2的形式。
         * @return URL所代表远程资源的响应
         */
        public static String sendPost(String url, String param) {
            PrintWriter out = null;
            BufferedReader in = null;
            String result = "";
            try {
                URL realUrl = new URL(url);
                // 打开和URL之间的连接
                URLConnection conn = realUrl.openConnection();
                // 设置通用的请求属性
                conn.setRequestProperty("accept", "*/*");
                conn.setRequestProperty("connection", "Keep-Alive");
                conn.setRequestProperty("user-agent",
                        "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
                // 发送POST请求必须设置如下两行
                conn.setDoOutput(true);
                conn.setDoInput(true);
                // 获取URLConnection对象对应的输出流
                out = new PrintWriter(conn.getOutputStream());
                // 发送请求参数
                out.print(param);
                // flush输出流的缓冲
                out.flush();
                // 定义BufferedReader输入流来读取URL的响应
                in = new BufferedReader(
                        new InputStreamReader(conn.getInputStream(),"UTF-8"));
                String line;
                while ((line = in.readLine()) != null) {
                    result += line;
                }
            } catch (Exception e) {
                System.out.println("发送POST请求出现异常！" + e);
                e.printStackTrace();
            }
            // 使用finally块来关闭输出流、输入流
            finally {
                try {
                    if (out != null) {
                        out.close();
                    }
                    if (in != null) {
                        in.close();
                    }
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
            return result;
        }
    
    }
  

调用

• 调用方式（详情参考lib下http文件夹中的附件）

    //String loginParam = "accessKey=test&accessSecret=test&clientId=clientId&clientType=PC";
      String loginParam = "accessKey=" + accessKey + "&accessSecret=" + accessSecret + "&clientId=" + clientId + "&clientType=" + clientType;
    
     //登陆接口：
      String loginUrl = "https://open.wellsign.cn/dandanqian/api/index.php/Conv/User/login";
    //loginParam = "accessKey=test&accessSecret=test&clientId=clientId&clientType=PC";
      String loginSuccess = HttpRequest.sendPost(loginUrl, loginParam);