微信开发（二）http请求工具类

深碍√TFBOYSˉ_ 2022-05-24 04:38 201阅读 0赞

# 说明 #

进行微信开发，后台程序需要与微信服务器进行交互，通过调用接口来完成服务，阅读微信开发文档，发现接口的调用都是通过http请求进行的，所以必须有个HttpUtil来支撑，这里总结下以javaAPI的方式和以Apach的HttpClient的方式进行HTTP请求

# 正文 #

## 使用java的HttpURLConnection ##

### 一个方法实现GET,POST请求 ###

public static String httpRequest(String requestUrl, String requestMethod, String outputStr){
            StringBuffer buffer = new StringBuffer();
            try {
                URL url = new URL(requestUrl);
                HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
                httpURLConnection.setDoInput(true);
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setUseCaches(false);
                httpURLConnection.setRequestMethod(requestMethod);
    
                if("GET".equalsIgnoreCase(requestMethod)){
                    httpURLConnection.connect();
                }
    
                if(null != outputStr){
                    OutputStream outputStream = httpURLConnection.getOutputStream();
                    outputStream.write(outputStr.getBytes("utf-8"));
                    outputStream.close();
                }
    
                InputStream inputStream = httpURLConnection.getInputStream();
                InputStreamReader inputStreamReader = new InputStreamReader(inputStream,"utf-8");
                BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
                String str = null;
                while((str = bufferedReader.readLine())!= null){
                    buffer.append(str);
                }
    
                bufferedReader.close();
                inputStreamReader.close();
                inputStream.close();
                httpURLConnection.disconnect();
            } catch (IOException e) {
                e.printStackTrace();
            }
    
            return buffer.toString();
        }

此方法通过指定URL,请求的方式和参数进行请求，使用流的方式发送参数和读取响应结果。该方法简单，没有设置http的请求属性等，示例代码在微信开发中可以实现功能。  
在此方法中 参数outputStr是向微信服务器发送的json格式的数据或者xml结构的数据，友好性不太好，通常应该传递Map<String,Object> params 保存参数

### Get请求 ###

private static final String CHAR_SET = "UTF-8";

public static String sendGet(String url, Map<String,Object> params){
            StringBuilder responseStr = null;
            StringBuilder paramsStr = new StringBuilder();
            if(params != null || params.size() > 0){
                for(Map.Entry<String,Object> entry : params.entrySet()){
                    paramsStr.append(entry.getKey());
                    paramsStr.append("=");
                    try {
                        paramsStr.append(URLEncoder.encode(String.valueOf(entry.getValue()),CHAR_SET));
                    } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                    paramsStr.append("&");
                }
            }
            URL URLstr = null;
            BufferedReader bufr = null;
            HttpURLConnection httpURLConnection = null;
            try {
                if(paramsStr != null && paramsStr.length() > 0){
                    url = url + "?" + paramsStr.substring(0,paramsStr.length() - 1);
                }
                URLstr = new URL(url);
                httpURLConnection = (HttpURLConnection) URLstr.openConnection();
                httpURLConnection.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
                httpURLConnection.connect();
                responseStr = new StringBuilder();
                bufr = new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream(),CHAR_SET));
                String str = null;
                while((str = bufr.readLine()) != null){
                    responseStr.append(str);
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                httpURLConnection.disconnect();
                if (bufr != null){
                    try {
                        bufr.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
            return  responseStr.toString();
        }

### Post请求 ###

public static String sendPost(String url, Map<String, Object> params){
            StringBuilder responseStr = null;
            StringBuilder paramsStr = new StringBuilder();
            if(params != null || params.size() > 0){
                for(Map.Entry<String,Object> entry : params.entrySet()){
                    paramsStr.append(entry.getKey());
                    paramsStr.append("=");
                    try {
                        paramsStr.append(URLEncoder.encode(String.valueOf(entry.getValue()),CHAR_SET));
                    } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                    paramsStr.append("&");
                }
            }
            URL URLstr = null;
            BufferedReader bufr = null;
            HttpURLConnection httpURLConnection = null;
            OutputStreamWriter osw = null;
            try {
                URLstr = new URL(url);
                httpURLConnection = (HttpURLConnection) URLstr.openConnection();
                httpURLConnection.setRequestMethod("POST");
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setDoInput(true);
                httpURLConnection.setUseCaches(false);
                if(paramsStr != null && paramsStr.length() > 0){
                    osw = new OutputStreamWriter(httpURLConnection.getOutputStream(),CHAR_SET);
                    osw.write(paramsStr.substring(0,paramsStr.length() - 1));
                    osw.flush();
                }
                bufr = new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream(),CHAR_SET));
                String str = null;
                while((str = bufr.readLine()) != null){
                    responseStr.append(str);
                }
    
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                if(osw != null){
                    try {
                        osw.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if(httpURLConnection != null) {
                    httpURLConnection.disconnect();
                }
                if(bufr != null){
                    try {
                        bufr.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
    
            }
            return responseStr.toString();
        }

通过对比sendGet和sendPost两种方法，发现不同之处有：

*  在创建URL对象时，sendGet方法的url是直接拼接了参数，而sendPost方法没有，sendPost方法通过OutputStremWriter对象将参数直接写出
 *  在创建了HttpURLConnection对象后，sendGet方法调用了connect()方法，sendPost没有调用此方法，但是显示设置了RequestMethod为POST
 *  在设置参数sendGet方法显示设置了“Content-Type”,sendPost则省略了，该参数可以不显示设置，关于“application/x-www-form-urlencoded”详细解释，为什么可以不显示设置，详见：[《HTTP中application/x-www-form-urlencoded字符说明》][HTTP_application_x-www-form-urlencoded]
 *  在sendPost方法中显示设置了DoOutput和DoInput为true，UseCaches为false

## 使用HttpClient ##

### Get请求 ###

public static String httpClienOfGet(String url,Map<String,Object> params){
            String res = "";
            StringBuilder paramsStr = null;
            if(params != null && params.size() > 0){
                for(Map.Entry<String,Object> entry : params.entrySet()){
                    paramsStr.append(entry.getKey());
                    paramsStr.append("=");
                    try {
                        paramsStr.append(URLEncoder.encode(String.valueOf(entry.getValue()),CHAR_SET));
                    } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                    paramsStr.append("&");
                }
            }
    
            if(paramsStr != null && paramsStr.length() > 0){
                url = url + "?" + paramsStr.substring(0,paramsStr.length() - 1);
            }
            HttpGet httpGet = new HttpGet(url);
            CloseableHttpClient httpClient = HttpClientBuilder.create().build();
            try {
                HttpResponse response = httpClient.execute(httpGet);
                if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
                    res = EntityUtils.toString(response.getEntity());
                }
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                if(httpClient != null){
                    try {
                        httpClient.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
    
            return res;
        }

### Post请求 ###

public static String httpClientOfPost(String url, Map<String, Object> params){
            String res = "";
            List<NameValuePair> paramList = new ArrayList<NameValuePair>();
            CloseableHttpClient httpClient = HttpClientBuilder.create().build();
            HttpPost  httpPost = new HttpPost(url);
    
            if(params != null && params.size() > 0){
                for(Map.Entry<String,Object> entry : params.entrySet()){
                    paramList.add(new BasicNameValuePair(entry.getKey(),String.valueOf(entry.getValue())));
                }
            }
    
            try {
                if(paramList.size() > 0){
                    UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(paramList,CHAR_SET);
                    httpPost.setEntity(urlEncodedFormEntity);
                }
                HttpResponse response = httpClient.execute(httpPost);
                if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
                    res = EntityUtils.toString(response.getEntity());
                }
            } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
            } catch (ClientProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                if(httpClient != null){
                    try {
                        httpClient.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
    
            return res;
        }

通过比较这两种方式，发现在创建请求方法时，对url处理不同，HttpGet的url直接拼接了参数，而HttpGet的url不做处理，参数则是通过了urlEncodedFormEntity 对象进行设置

### 通过Post请求发送接收json格式的数据 ###

在微信开发时，通常要通过http发送json格式的数据，微信服务器返回的是json数据，包含了code和msg

public static String jsonOfPost(String url, String param){
            String res = "";
            DefaultHttpClient client = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setHeader("Accept","application/json");
            httpPost.setHeader("Content-Type","application/json");
            String charSet = "UTF-8";
            HttpResponse response = null;
    
            try {
                StringEntity entity = new StringEntity(param,charSet);
                entity.setContentEncoding(charSet);
                entity.setContentType("application/json");
                httpPost.setEntity(entity);
                response = client.execute(httpPost);
                StatusLine statusLine = response.getStatusLine();
                int state = statusLine.getStatusCode();
                if(state == org.apache.http.HttpStatus.SC_OK){
                    HttpEntity responseEntity = response.getEntity();
                    res = EntityUtils.toString(responseEntity);
                    return res;
                }else{
                    System.out.println("请求出错");
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return res;
        }

关于http的请求总结到这里，有关于POST和GET请求的区别，详见：  
[https://blog.csdn.net/yaojianyou/article/details/1720913/][https_blog.csdn.net_yaojianyou_article_details_1720913]  
[http://www.nowamagic.net/librarys/veda/detail/1919][http_www.nowamagic.net_librarys_veda_detail_1919]

参考的优秀博文：  
[https://www.cnblogs.com/mengrennwpu/p/6418114.html][https_www.cnblogs.com_mengrennwpu_p_6418114.html]  
[https://blog.csdn.net/u010197591/article/details/51441399][https_blog.csdn.net_u010197591_article_details_51441399]  
[https://blog.csdn.net/qq9808/article/details/78320816][https_blog.csdn.net_qq9808_article_details_78320816]

[HTTP_application_x-www-form-urlencoded]: https://blog.csdn.net/qq_28702545/article/details/51719199
[https_blog.csdn.net_yaojianyou_article_details_1720913]: https://blog.csdn.net/yaojianyou/article/details/1720913/
[http_www.nowamagic.net_librarys_veda_detail_1919]: http://www.nowamagic.net/librarys/veda/detail/1919
[https_www.cnblogs.com_mengrennwpu_p_6418114.html]: https://www.cnblogs.com/mengrennwpu/p/6418114.html
[https_blog.csdn.net_u010197591_article_details_51441399]: https://blog.csdn.net/u010197591/article/details/51441399
[https_blog.csdn.net_qq9808_article_details_78320816]: https://blog.csdn.net/qq9808/article/details/78320816

发表评论取消回复

表情：

评论列表（有 0 条评论，201人围观）

还没有评论，来说两句吧...

相关阅读

相关 http请求工具类

package com.template.utils.http; import cn.hutool.core.map.MapUtil; imp

今天药忘吃喽~/ 2024年04月01日 13:59/ 0 赞/ 110 阅读

相关 JAVA http请求工具类

目录 1. 第一种http-requst 1)maven引入 2)Get请求请求示例 3)post请求请求示例 2、第二种Hutool 1)maven引入 2)

布满荆棘的人生/ 2023年10月01日 12:54/ 0 赞/ 76 阅读

相关 HTTP请求工具类

package cn.my.utils; import lombok.extern.log4j.Log4j2; import org.apac

古城微笑少年丶/ 2023年09月28日 21:36/ 0 赞/ 50 阅读

相关 HttpsUtils工具类 https请求工具类

import java.io.InputStream; import java.io.OutputStream; import java.net.Htt

曾经终败给现在/ 2023年01月19日 10:53/ 0 赞/ 256 阅读

相关微信小程序开发实战（21）：发起HTTPS请求

在wx对象中有一个request方法，可以发起HTTPS请求。该方法只有一个对象类型参数。该对象支持如下所示。 url：String类型，必选，开发者服务器接口地址，

向右看齐/ 2022年11月29日 11:37/ 0 赞/ 309 阅读

相关发送http请求工具类

import java.io.IOException; import java.net.URI; import java.util.ArrayList;

超、凢脫俗/ 2022年05月29日 08:09/ 0 赞/ 287 阅读

相关微信开发（二）http请求工具类

说明进行微信开发，后台程序需要与微信服务器进行交互，通过调用接口来完成服务，阅读微信开发文档，发现接口的调用都是通过http请求进行的，所以必须有个Http

深碍√TFBOYSˉ_/ 2022年05月24日 04:38/ 0 赞/ 202 阅读

相关模拟http请求工具类

package cartest; import java.io.BufferedReader; import java.io.IOException; imp

「爱情、让人受尽委屈。」/ 2022年05月21日 07:49/ 0 赞/ 268 阅读

相关 HTTP请求工具类

HttpClientUtil 4.3.6 > package org.caeit.cloud.dev.util; > > import java.io.File; >

ゝ一纸荒年。/ 2022年02月20日 00:57/ 0 赞/ 378 阅读

相关 HTTP请求java工具类

package org.rd.cc.csr.util; import java.io.IOException; import java.nio

向右看齐/ 2021年09月14日 04:48/ 0 赞/ 430 阅读