Spring Boot发送http请求

因为项目要调用第三方网站接口获取信息（类似python爬虫），所以在后端项目中需要前端axios一样去构建请求获取信息。下面用简单的获取IP地址为例。

java 复制代码

@Slf4j
public class IPTest {

    // IP地址查询
    public static final String IP_URL = "http://whois.pconline.com.cn/ipJson.jsp";

    // 未知地址
    public static final String UNKNOWN = "未知地址";

    private String getRealAddressByIP(String ip) {
        String address = UNKNOWN;

        if (true) {
            try {
                String rspStr = sendGet(IP_URL, "ip=" + ip + "&json=true" ,"GBK");
                if (StrUtil.isEmpty(rspStr)) {
                    return UNKNOWN;
                }
                JSONObject obj = JSONObject.parseObject(rspStr);
                String addr = obj.getString("addr");
                return String.format("%s" , addr);
            } catch (Exception e) {
            }
        }
        return address;
    }


     private String sendGet(String url, String param, String contentType) {
        StringBuilder result = new StringBuilder();
        BufferedReader in = null;
        try {
            String urlNameString = url + "?" + param;
            URL realUrl = new URL(urlNameString);
            URLConnection connection = realUrl.openConnection();
            connection.setRequestProperty("accept" , "*/*");
            connection.setRequestProperty("connection" , "Keep-Alive");
            connection.setRequestProperty("User-Agent","Mozilla/4.0 compatible; MSIE 6.0; Windows NT 5.1;DigExt");
            connection.connect();
            in = new BufferedReader(new InputStreamReader(connection.getInputStream(), contentType));
            String line;
            while ((line = in.readLine()) != null) {
                result.append(line);
            }
        } catch (ConnectException e) {   
        } catch (SocketTimeoutException e) {
        } catch (IOException e) {
        } catch (Exception e) {
        } finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception ex) {
            }
        }
        return result.toString();
    }


    public static void main(String[] args) {
        String ipaddr = getRealAddressByIP(你的ip);
        String address = ipaddr.equals("未知地址") ? "位置获取失败" : ipaddr;
        log.info(address);
    }
}

有些网站会做反爬机制，所以在创建URL的时候，加上这句 connection.setRequestProperty("User-Agent","Mozilla/4.0 compatible; MSIE 6.0; Windows NT 5.1;DigExt");可以解决大部分问题