java后台http请求方式

长时间没有写这方面的代码，突然提笔对于http的请求方式代码不知道如何下手，特此记录一下

public JSONObject  doPost(String url) throws IOException {
    HttpClient httpClient = new HttpClient();
    PostMethod postMethod = new PostMethod(url);

    postMethod.addRequestHeader("accept", "*/*");
    postMethod.addRequestHeader("connection", "Keep-Alive");
    //设置json格式传送
    postMethod.addRequestHeader("Content-Type", "application/json;charset=utf-8");
    //必须设置下面这个Header
    postMethod.addRequestHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36");
    //添加请求参数
    JSONObject jsonObject = new JSONObject();
    jsonObject.put("url", "www.baidu.com");
    RequestEntity se = new StringRequestEntity(jsonObject.toString(), "application/json", "utf-8");
    postMethod.setRequestEntity(se);
    httpClient.executeMethod(postMethod);
    String responseMsg = postMethod.getResponseBodyAsString().trim();
    JSONObject returnJson = JSONObject.parseObject(responseMsg);
    return returnJson;
}

http请求方式有多种，参考链接：https://www.cnblogs.com/hhhshct/p/8523697.html