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工具类

//GET///**     * get请求     *     * @param url   目标地址     * @param param 参数     * @return String 响应信息     */    public static String sendGet(String url, String param) {           String result = "";        BufferedReader in = null;        try {               String urlNameString = url + "?" + param;            URL realUrl = new URL(urlNameString);            // 打开和URL之间的连接            URLConnection connection = realUrl.openConnection();            // 设置通用的请求属性            connection.setRequestProperty("accept", "*/*");            connection.setRequestProperty("connection", "Keep-Alive");            connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");            // 建立连接            connection.connect();            // 定义 BufferedReader读取URL的响应            in = new BufferedReader(new InputStreamReader(connection.getInputStream(), StandardCharsets.UTF_8));            String line;            while ((line = in.readLine()) != null) {                   result += line;            }        } catch (Exception e) {               log.error("GET请求异常{}" , e.getMessage());        } finally {               try {                   if (in != null) {                       in.close();                }            } catch (Exception e2) {                   e2.getMessage();            }        }        return result;    }////////////////////////////////POST///////////////////////////    /**     * 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，json     * @return 响应结果     */    public static String sendPost(String url, String param) {           OutputStreamWriter out = null;        BufferedReader in = null;        String result = "";        //创建连接        try {               URL httpUrl = null; //HTTP URL类 用这个类来创建连接            //创建URL            httpUrl = new URL(url);            //建立连接            HttpURLConnection conn = (HttpURLConnection) httpUrl.openConnection();            conn.setRequestMethod("POST");            conn.setRequestProperty("Content-Type", "application/json");            conn.setRequestProperty("connection", "keep-alive");            conn.setUseCaches(false);//缓存关闭            conn.setInstanceFollowRedirects(true);            conn.setDoOutput(true);            conn.setDoInput(true);            conn.connect();            //POST请求            out = new OutputStreamWriter(conn.getOutputStream());            out.write(param);            out.flush();            //读取响应            in = new BufferedReader(new InputStreamReader(conn.getInputStream(), StandardCharsets.UTF_8));            String line;            while ((line = in.readLine()) != null) {                   result += line;            }            in.close();            // 断开连接            conn.disconnect();        } catch (Exception e) {               log.error("发送 POST 请求出现异常！{}" , e.getMessage());        }        //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.getMessage();            }        }        return result;    }///PUT/    /**     * put请求     *     * @param url 目标地址     * @param map 参数     * @return String响应结果     */    public static String sendPut(String url, Map map) {           String encode = "utf-8";        CloseableHttpClient closeableHttpClient = HttpClients.createDefault();        HttpPut httpput = new HttpPut(url);        httpput.setHeader("Accept", "*/*");        httpput.setHeader("Accept-Encoding", "gzip, deflate");        httpput.setHeader("Cache-Control", "no-cache");        httpput.setHeader("Connection", "keep-alive");        httpput.setHeader("Content-Type", "application/json;charset=UTF-8");        //请求参数处理        StringEntity stringEntity = new StringEntity(JSON.toJSONString(map), encode);        httpput.setEntity(stringEntity);        String content = null;        CloseableHttpResponse httpResponse = null;        try {               //响应信息            httpResponse = closeableHttpClient.execute(httpput);            HttpEntity entity = httpResponse.getEntity();            content = EntityUtils.toString(entity, encode);        } catch (Exception e) {               e.printStackTrace();        } finally {               try {                   httpResponse.close();            } catch (IOException e) {                   e.getMessage();            }        }        try {               closeableHttpClient.close();  //关闭连接、释放资源        } catch (IOException e) {               e.getMessage();        }        return content;    }/////////////////////////////socket////////////////////////	/**     * socket发送数据     *     * @param text 数据     * @param host 地址     * @param port 端口     */    public static void forwardSocket(String text, String host, Integer port) {           Socket socket = null;        OutputStream outputStream = null;        DataOutputStream dataOutputStream = null;        try {               socket = new Socket(host, port);            outputStream = socket.getOutputStream();            //把输出流封装在DataOutputStream中            dataOutputStream = new DataOutputStream(outputStream);            //使用writeUTF发送字符串            dataOutputStream.writeUTF(text);            dataOutputStream.close();            socket.close();        } catch (IOException e) {               log.error("socket发送数据-失败{}", e.getMessage());        } finally {               try {                   if (dataOutputStream != null) {                       dataOutputStream.close();                }                if (socket != null) {                       socket.close();                }            } catch (Exception ex) {                   log.error("error to socket close :{}", ex.getMessage());            }        }    }

使用案例

get就不多说了

/**     * 上传信息     */    @RequestMapping(value = "/uploadEmp", method = RequestMethod.POST)    @ResponseBody    public JsonData uploadData(Demo emp) {           int code = 1;        String message = "";        try {               String result = GetPostPutUtil.sendPost("http://xxx:1012/api/demo", JSON.toJSONString(emp));//实体类对象json化，alibaba.fastjson            //获取响应状态            boolean contains1 = result.contains("\"code\":");            if (contains1) {                   code = Integer.parseInt(result.split("\"code\":")[1].split(",", 0)[0]);            }            //获取响应信息            boolean contains2 = result.contains("\"message\":\"");            if (contains2) {                   message = result.split("\"message\":\"")[1].split("\"}", 0)[0];            }   ///省略//   }      响应结果：{   "code":0,"message":"上传成功"}

PUT请求

/**     * 删除     *     * @return String     */    @RequestMapping(value = "/deleteDemo")    @ResponseBody    public String deleteDemo() {           List
   
     id = new ArrayList();        id.add("000012");        HashMap
    
      map = new HashMap
     
      ();        map.put("demoName", "张三");        map.put("id", id);        return GetPostPutUtil.sendPut("http://xxxx:1012/api/delete", map);    }    响应结果：{   "code":0,"message":"删除成功"}