通过HttpURLConnection发送GET和POST请求（解决转义码问题）

╰+攻爆jí腚メ 2023-03-13 06:42 13阅读 0赞

通过HttpURLConnection发送GET和POST请求

public class HttpURLConnectionDemo {
    	/**
         * get
         * @param httpUrl 请求
         * @param encode 编码
         * @return
         */
        public static String deGet(String httpUrl,String encode){
            if(encode == "" || encode == null){
                //设置默认编码
                encode = "utf-8";
            }
            HttpURLConnection conn = null;
            InputStream is = null;
            BufferedReader br = null;
            StringBuilder result = new StringBuilder();
    
            try{
                //创建远程url连接对象
                URL url = new URL(httpUrl);
                //通过远程url连接对象打开一个连接，强转成HTTPURLConnection类
                conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("GET");
                //设置连接超时时间和读取超时时间
                conn.setConnectTimeout(15000);
                conn.setReadTimeout(60000);
                conn.setRequestProperty("Accept", "application/json");
                //发送请求
                conn.connect();
                //通过conn取得输入流，并使用Reader读取
                if (HttpURLConnection.HTTP_OK == conn.getResponseCode()){
                    is = conn.getInputStream();
                    br = new BufferedReader(new InputStreamReader(is, encode));
                    String line;
                    while ((line = br.readLine()) != null){
                        result.append(line);
                        System.out.println(line);
                    }
                }else{
                    System.out.println("ResponseCode is an error code:" + conn.getResponseCode());
                }
            }catch (MalformedURLException e){
                e.printStackTrace();
            }catch (IOException e){
                e.printStackTrace();
            }catch (Exception e){
                e.printStackTrace();
            }finally {
                try{
                    if(br != null){
                        br.close();
                    }
                    if(is != null){
                        is.close();
                    }
                }catch (IOException ioe){
                    ioe.printStackTrace();
                }
                conn.disconnect();
            }
            return result.toString();
        }
    
        /**
         * post
         * @param httpUrl 请求
         * @param encode 编码
         * @return
         */
        public static String doPost(String httpUrl,String encode){
            if(encode == "" || encode == null){
                //设置默认编码
                encode = "utf-8";
            }
            OutputStreamWriter out = null;
            BufferedReader in = null;
            StringBuilder result = new StringBuilder();
            HttpURLConnection conn = null;
            try{
                URL url = new URL(httpUrl);
                conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("POST");
                //发送POST请求必须设置为true
                conn.setDoOutput(true);
                conn.setDoInput(true);
                //设置连接超时时间和读取超时时间
                conn.setConnectTimeout(30000);
                conn.setReadTimeout(10000);
                conn.setRequestProperty("Content-Type", "application/json");
                conn.setRequestProperty("Accept", "application/json");
                //获取输出流
                out = new OutputStreamWriter(conn.getOutputStream());
                String jsonStr = "{\"qry_by\":\"name\", \"name\":\"Tim\"}";
                out.write(jsonStr);
                out.flush();
                out.close();
                //取得输入流，并使用Reader读取
                if (HttpURLConnection.HTTP_OK == conn.getResponseCode()){
                    in = new BufferedReader(new InputStreamReader(conn.getInputStream(), encode));
                    String line;
                    while ((line = in.readLine()) != null){
                        result.append(line);
                        System.out.println(line);
                    }
                }else{
                    System.out.println("ResponseCode is an error code:" + conn.getResponseCode());
                }
            }catch (Exception e){
                e.printStackTrace();
            }finally {
                try{
                    if(out != null){
                        out.close();
                    }
                    if(in != null){
                        in.close();
                    }
                }catch (IOException ioe){
                    ioe.printStackTrace();
                }
            }
            return result.toString();
        }
    
        public static void main(String[] args) {
            String url = "http://57.145.140.145:7776/tyc/getTycInfo?params=%7B%22id%22:%22%22,%22name%22:%22%E5%9B%9B%E5%B7%9D%E5%B7%9D%E5%A4%A7%E6%99%BA%E8%83%9C%E7%B3%BB%E7%BB%9F%E9%9B%86%E6%88%90%E6%9C%89%E9%99%90%E5%85%AC%E5%8F%B8%22%7D&url=http:%2F%2Fopen.api.tianyancha.com%2Fservices%2Fv4%2Fopen%2Fpast%2Fic";
            System.out.println(deGet(url,""));
        }
    
    }

## 关于转义码问题 ##

发现如果是浏览器拷贝过来字符通过了  
String url = “http://57.145.140.145:7776/tyc/getTycInfo?params=%7B%22id%22:%22%22,%22name%22:%22%E5%9B%9B%E5%B7%9D%E5%B7%9D%E5%A4%A7%E6%99%BA%E8%83%9C%E7%B3%BB%E7%BB%9F%E9%9B%86%E6%88%90%E6%9C%89%E9%99%90%E5%85%AC%E5%8F%B8%22%7D&url=http:%2F%2Fopen.api.tianyancha.com%2Fservices%2Fv4%2Fopen%2Fpast%2Fic”;  
而没有转义符的会出现400错误

#### 原因是编码问题 ####

文件格式可能不是utf-8，我们可以把参数在统一转码一下。

String url2 = null;
            try {
                url2 = "http://58.130.66.120/gzeimm_web/capDec2/getEnpFillInfo.rpcc?parameter=" +
                        URLEncoder.encode("{\"date\":\"2020-05-11\"}", "UTF-8");
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
            String url3= "http://58.130.66.120/gzeimm_web/capDec2/getEnpFillInfo.rpcc?parameter={%22date%22:%222020-05-11%22}%22";

上面两个请求是正常滴。  
建议在方法中对参数转码

## 关于参数建议 ##

参数我们可以用map添加

Map<String, String> param = new HashMap<String, String>();
    			param.put("report_period", "2020-5");
    			param.put("pageSize", "10");
    			param.put("pageIndex", "1");

方法中把map放入url中，调用方法时清晰方便。