Java中发送请求的工具类

post参数:{}--json字符串

package com.hjkj.facecomparison.utils;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpConnectionUtil {

    public static String doGet(String httpUrl) throws Exception {
        //链接
        HttpURLConnection connection = null;
        InputStream is = null;
        BufferedReader br = null;
        StringBuffer result = new StringBuffer();
        try {
            //创建连接
            URL url = new URL(httpUrl);
            connection = (HttpURLConnection) url.openConnection();
            //设置请求方式
            connection.setRequestMethod("GET");
            //设置连接超时时间
            connection.setReadTimeout(15000);
            //开始连接
            connection.connect();
            //获取响应数据
            if (connection.getResponseCode() == 200) {
                //获取返回的数据
                is = connection.getInputStream();
                if (null != is) {
                    br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
                    String temp = null;
                    while (null != (temp = br.readLine())) {
                        result.append(temp);
                    }
                }
            }
        } catch (IOException e) {
            throw new Exception("发起get请求失败", e);
        } finally {
            closeStream(br, is, null, connection);
        }
        return result.toString();
    }

    /**
     * Http post请求
     * @param httpUrl 连接
     * @param param 参数
     * @return
     */
    public static String doPost(String httpUrl, String param) throws Exception {
        StringBuffer result = new StringBuffer();
        //连接
        HttpURLConnection connection = null;
        OutputStream os = null;
        InputStream is = null;
        BufferedReader br = null;
        try {
            //创建连接对象
            URL url = new URL(httpUrl);
            //创建连接
            connection = (HttpURLConnection) url.openConnection();
            //设置请求方法
            connection.setRequestMethod("POST");
            //设置连接超时时间
            connection.setConnectTimeout(15000);
            //设置读取超时时间
            connection.setReadTimeout(15000);
            //DoOutput设置是否向httpUrlConnection输出，DoInput设置是否从httpUrlConnection读入，此外发送post请求必须设置这两个
            //设置是否可读取
            connection.setDoOutput(true);
            connection.setDoInput(true);
            //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)");
            connection.setRequestProperty("Content-Type", "application/json;charset=utf-8");

            //拼装参数
            if (null != param && !param.equals("")) {
                //设置参数
                os = connection.getOutputStream();
                //拼装参数
                os.write(param.getBytes("UTF-8"));
            }

            //读取响应
            //if (connection.getResponseCode() == 200) {
                is = connection.getInputStream();
                if (null != is) {
                    br = new BufferedReader(new InputStreamReader(is, "utf8"));
                    String temp = null;
                    while (null != (temp = br.readLine())) {
                        result.append(temp);
                        result.append("\r\n");
                    }
                }
//            }

        } catch (IOException e) {
            throw new Exception("发起post请求失败", e);
        } finally {
            closeStream(br, is, os, connection);
        }
        return result.toString();
    }

    /**
     * 关闭流和http连接
     */
    public static void closeStream(BufferedReader br, InputStream is, OutputStream os, HttpURLConnection connection) throws Exception {
        //关闭连接
        if(br!=null){
            try {
                br.close();
            } catch (IOException e) {
                throw new Exception("关闭BufferedReader流失败", e);
            }
        }
        if(os!=null){
            try {
                os.close();
            } catch (IOException e) {
                throw new Exception("关闭OutputStream流失败", e);
            }
        }
        if(is!=null){
            try {
                is.close();
            } catch (IOException e) {
                throw new Exception("关闭InputStream流失败", e);
            }
        }
        //关闭连接
        connection.disconnect();
    }



}

```

- 例子

package com.hjkj.facecomparison.controller;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.hjkj.facecomparison.common.ResponseResult;
import com.hjkj.facecomparison.person.Person;
import com.hjkj.facecomparison.utils.HttpConnectionUtil;
import com.pinecone.utils.EncryptionUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import javax.validation.Valid;

/**

• 人脸比对处理类
  */
  @RestController
  public class FaceComparisonController {

  @Value("{face.requestUrl}")
  private String requestUrl;
  @Value("${face.clientCode}")
  private String clientCode;

  /**

  • 获取比对结果
  • @param person {"nameText":"",numberText:"",idPhoto:""}
  • @return json
    */
    @PostMapping(value = "/comparisonResult")
    @ResponseBody
    public ResponseResult faceComparisonResult(@RequestBody @Valid Person person) throws Exception {
    JSONObject source = new JSONObject();
    source.put("clientCode", clientCode);
    source.put("encryptString", EncryptionUtils.encryptSM4(sm4Key, JSON.toJSONString(person)));
    // return HttpConnectionUtil.doPost(requestUrl, source.toString());
    JSONObject jsonObject = JSON.parseObject(HttpConnectionUtil.doPost(requestUrl, source.toString()));
    String result = jsonObject.getString("result");
    if (result != null && result.equals("-1")) {
    return ResponseResult.error(result, jsonObject.getString("errCode"),
    jsonObject.getString("resultDetail"), "比对失败");
    }
    return ResponseResult.success(jsonObject.getString("result"), jsonObject.getString("similarity"), jsonObject.getString("resultDetail"));

  }

}