java发起http请求获取返回的Json对象

ゝ一纸荒年。 2022-05-19 20:45 237阅读 0赞

/** * Created by david on 2017-7-5. */
    import com.google.gson.JsonObject;
    import com.google.gson.JsonParser;
    
    import java.io.BufferedInputStream;
    import java.io.BufferedReader;
    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.io.PrintWriter;
    import java.net.HttpURLConnection;
    import java.net.URL;
    
    public class HttpRequestUtil { 
        /** * 发起http请求并获取结果 * @param requestUrl 请求地址 */
        public static JsonObject getXpath(String requestUrl){
            String res="";
            JsonObject object = null;
            StringBuffer buffer = new StringBuffer();
            try{
                URL url = new URL(requestUrl);
                HttpURLConnection urlCon= (HttpURLConnection)url.openConnection();
                if(200==urlCon.getResponseCode()){
                    InputStream is = urlCon.getInputStream();
                    InputStreamReader isr = new InputStreamReader(is,"utf-8");
                    BufferedReader br = new BufferedReader(isr);
    
                    String str = null;
                    while((str = br.readLine())!=null){
                        buffer.append(str);
                    }
                    br.close();
                    isr.close();
                    is.close();
                    res = buffer.toString();
                    JsonParser parse =new JsonParser();
                    object = (JsonObject) parse.parse(res);
                }
            }catch(IOException e){
                e.printStackTrace();
            }
            return object;
        }
    
       public static JsonObject postDownloadJson(String path,String post){
            URL url = null;
            try {
                url = new URL(path);
                HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
                httpURLConnection.setRequestMethod("POST");// 提交模式
                // conn.setConnectTimeout(10000);//连接超时 单位毫秒
                // conn.setReadTimeout(2000);//读取超时 单位毫秒
                // 发送POST请求必须设置如下两行
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setDoInput(true);
                // 获取URLConnection对象对应的输出流
                PrintWriter printWriter = new PrintWriter(httpURLConnection.getOutputStream());
                // 发送请求参数
                printWriter.write(post);//post的参数 xx=xx&yy=yy
                // flush输出流的缓冲
                printWriter.flush();
                //开始获取数据
                BufferedInputStream bis = new BufferedInputStream(httpURLConnection.getInputStream());
                ByteArrayOutputStream bos = new ByteArrayOutputStream();
                int len;
                byte[] arr = new byte[1024];
                while((len=bis.read(arr))!= -1){
                    bos.write(arr,0,len);
                    bos.flush();
                }
                bos.close();
                JsonParser parse = new JsonParser();
                return (JsonObject)parse.parse(bos.toString("utf-8"));
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }
    
        //测试
        public static void main(String args [] ) {
            JsonObject res = null;
    // res = getXpath("http://ip.taobao.com/service/getIpInfo.php?ip=63.223.108.42");
            res = postDownloadJson("http://ip.taobao.com/service/getIpInfo.php?","ip=63.223.108.42");
            System.out.println(res);
    // System.out.println(res.get("code"));
    // System.out.println(res.get("data"));
        }
    }

看第一个方法，发送get请求获取后台数据，其中，将返回回来的字符串解析成json对象用到了google的Gson.jar包，用到了其中JsonParser的parse方法。

第二个方法，发送post数据到后台并获取后台数据。

转载自：[https://blog.csdn.net/jeanflower/article/details/74494136][https_blog.csdn.net_jeanflower_article_details_74494136]

[https_blog.csdn.net_jeanflower_article_details_74494136]: https://blog.csdn.net/jeanflower/article/details/74494136