public static void main(String[] args) throws MalformedURLException {        BufferedReader in = null;        String result = null;        try {            URL url = new URL("http://www.baidu.com");            in = new BufferedReader(new InputStreamReader(url.openStream(), "UTF-8"));            StringBuffer sb = new StringBuffer();            String str = null;            while ((str = in.readLine()) != null) {                sb.append(str);            }            result = sb.toString();            System.out.println(result);        } catch (Exception ex) {        } finally {            if (in != null) {                try {                    in.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }    } 返回的是:

       
      
      
      
          
      
 
       
 
        
 
         
 
          
 
           
 
             
           
 
           
 
             
             
             
             
             
            
            
             
           
 
          
 
         
 
         
 
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三种连接方法:

// 方法一              URL url = new URL("http://www.sina.com.cn");             URLConnection urlcon = url.openConnection();             InputStream is = urlcon.getInputStream();                          // 方法二             URL url = new URL("http://www.yhfund.com.cn");             HttpURLConnection urlcon = (HttpURLConnection)url.openConnection();             InputStream is = urlcon.getInputStream();                         //方法三             URL url = new URL("http://www.yhfund.com.cn");             InputStream is = url.openStream();

 

 

/**     * 调用数据同步     * @param date 当前日期 格式yyyy-MM-dd     * @param totalExclusion 传入“”字符串     * @return 返回结果     */    public static String queryDataSynStatus(String date, String totalExclusion) {        try {            System.out.println("Data Collection Date: " + date);            if (date == null)                return "Data Synchronized Failure!";            System.out.println("Data Synchronized Start!");            String local = "http://localhost:7070/a/b.do";            HashMap
      
        params = new HashMap
       
        ();            params.put("date", date);            params.put("totalExclusion", totalExclusion);            StringBuffer sb = new StringBuffer();            for (String key : params.keySet()) {                sb.append(key).append("=")                        .append(params.get(key) != null ? params.get(key) : "")                        .append("&");            }            sb.deleteCharAt(sb.length() - 1);            // 新增接口            String param = HttpRequest.sendPost(local, sb.toString());            System.out.println(param);            System.out.println("Data Synchronized End!");        } catch (Exception e) {            e.printStackTrace();        }        return "Data Synchronized Successfully!";    }
       
      

/**     * 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 所代表远程资源的响应结果     */    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();            conn.setRequestProperty("Host", "www.baidu.com");            conn.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");            conn.setRequestProperty("Accept-Language", "zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3");            conn.setRequestProperty("Accept-Encoding", "gzip, deflate");            conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");            conn.setRequestProperty("Content-Length", "37");            conn.setRequestProperty("Cookie", "JSESSIONID=************************");            conn.setRequestProperty("Connection", "keep-alive");            conn.setRequestProperty("Pragma", "no-cache");            conn.setRequestProperty("Cache-Control", "no-cache");            // 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("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;    }