JAVA后台POST/GET访问方法

    
  // 发送post请求
  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()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("[POST请求]向地址:" + url + " 发送数据:" + param + " 发生错误!");
        } finally {// 使用finally块来关闭输出流、输入流
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                System.out.println("关闭流异常");
            }
        }
        return result;
    }

  //发送GET请求
    public static String sendGet(String url) {
        String result = "";
        BufferedReader in = null;
        try {
            String urlName = url;
            URL realUrl = new URL(urlName);
            URLConnection conn = realUrl.openConnection();// 打开和URL之间的连接
            conn.setRequestProperty("accept", "*/*");// 设置通用的请求属性
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
            conn.setConnectTimeout(4000);
            conn.connect();// 建立实际的连接
            in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));// 定义BufferedReader输入流来读取URL的响应
            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);
        } finally {// 使用finally块来关闭输入流
            try {
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                System.out.println("关闭流异常");
            }
        }
        return result;
    }
 
原文地址:https://www.cnblogs.com/timjames/p/8072517.html