一、概述

在實際開發(fā)過程中，我們經(jīng)常需要調(diào)用對方提供的接口或者自己寫的接口是否有接口。短信、天氣等）。

Java項目中調(diào)用接口的方式有：

通過JDK網(wǎng)絡(luò)類Java.net.HttpURLConnection；

通過common封裝好HttpClient；

通過 Apache 封裝好CloseableHttpClient；

通過SpringBoot-RestTemplate；

基于 Spring Boot + MyBatis Plus + Vue & Element 實現(xiàn)的后臺管理系統(tǒng) + 用戶小程序，支持 RBAC 動態(tài)權(quán)限、多租戶、數(shù)據(jù)權(quán)限、工作流、三方登錄、支付、短信、商城等功能

項目地址：https://gitee.com/zhijiantianya/ruoyi-vue-pro

視頻教程：https://doc.iocoder.cn/video/

二、Java調(diào)用http接口的方式

2.1、通過JDK網(wǎng)絡(luò)類Java.net.HttpURLConnection

原始比較的一種調(diào)用方法，這里get請求和post請求都可以找到一個方法里面。

實現(xiàn)過程：

得到：

創(chuàng)建遠程連接

設(shè)置連接方式（get、post、put。。。）

設(shè)置連接時間

設(shè)置響應(yīng)讀取時間

發(fā)起請求

獲取請求數(shù)據(jù)

關(guān)閉連接

郵政：

創(chuàng)建遠程連接

設(shè)置連接方式（get、post、put。。。）

設(shè)置連接時間

設(shè)置響應(yīng)讀取時間

當(dāng)向遠程服務(wù)器傳送數(shù)據(jù)/寫入數(shù)據(jù)時，需要設(shè)置為true（setDoOutput）

當(dāng)前向遠程服務(wù)讀取數(shù)據(jù)時，設(shè)置為true，該參數(shù)可有可無（setDoInput）

設(shè)置參數(shù)格式的屬性：（請求參數(shù)）

設(shè)置鑒權(quán)信息：授權(quán)：（setRequestProperty）

參數(shù)設(shè)置

發(fā)起請求

獲取請求數(shù)據(jù)

關(guān)閉連接

直接上代碼：

?

?

package?com.riemann.springbootdemo.util.common.httpConnectionUtil;
?
import?org.springframework.lang.Nullable;
?
import?java.io.*;
import?java.net.HttpURLConnection;
import?java.net.MalformedURLException;
import?java.net.URL;
import?java.net.URLConnection;
?
/**
?*?@author?riemann
?*/
public?class?HttpURLConnectionUtil?{
?
????/**
?????*?Http?get請求
?????*?@param?httpUrl?連接
?????*?@return?響應(yīng)數(shù)據(jù)
?????*/
????public?static?String?doGet(String?httpUrl){
????????//鏈接
????????HttpURLConnection?connection?=?null;
????????InputStream?is?=?null;
????????BufferedReader?br?=?null;
????????StringBuffer?result?=?new?StringBuffer();
????????try?{
????????????//創(chuàng)建連接
????????????URL?url?=?new?URL(httpUrl);
????????????connection?=?(HttpURLConnection)?url.openConnection();
????????????//設(shè)置請求方式
????????????connection.setRequestMethod("GET");
????????????//設(shè)置連接超時時間
????????????connection.setReadTimeout(15000);
????????????//開始連接
????????????connection.connect();
????????????//獲取響應(yīng)數(shù)據(jù)
????????????if?(connection.getResponseCode()?==?200)?{
????????????????//獲取返回的數(shù)據(jù)
????????????????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)?{
????????????e.printStackTrace();
????????}?finally?{
????????????if?(null?!=?br)?{
????????????????try?{
????????????????????br.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????????if?(null?!=?is)?{
????????????????try?{
????????????????????is.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????????//關(guān)閉遠程連接
????????????connection.disconnect();
????????}
????????return?result.toString();
????}
?
????/**
?????*?Http?post請求
?????*?@param?httpUrl?連接
?????*?@param?param?參數(shù)
?????*?@return
?????*/
????public?static?String?doPost(String?httpUrl,?@Nullable?String?param)?{
????????StringBuffer?result?=?new?StringBuffer();
????????//連接
????????HttpURLConnection?connection?=?null;
????????OutputStream?os?=?null;
????????InputStream?is?=?null;
????????BufferedReader?br?=?null;
????????try?{
????????????//創(chuàng)建連接對象
????????????URL?url?=?new?URL(httpUrl);
????????????//創(chuàng)建連接
????????????connection?=?(HttpURLConnection)?url.openConnection();
????????????//設(shè)置請求方法
????????????connection.setRequestMethod("POST");
????????????//設(shè)置連接超時時間
????????????connection.setConnectTimeout(15000);
????????????//設(shè)置讀取超時時間
????????????connection.setReadTimeout(15000);
????????????//DoOutput設(shè)置是否向httpUrlConnection輸出，DoInput設(shè)置是否從httpUrlConnection讀入，此外發(fā)送post請求必須設(shè)置這兩個
????????????//設(shè)置是否可讀取
????????????connection.setDoOutput(true);
????????????connection.setDoInput(true);
????????????//設(shè)置通用的請求屬性
????????????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");
?
????????????//拼裝參數(shù)
????????????if?(null?!=?param?&&?param.equals(""))?{
????????????????//設(shè)置參數(shù)
????????????????os?=?connection.getOutputStream();
????????????????//拼裝參數(shù)
????????????????os.write(param.getBytes("UTF-8"));
????????????}
????????????//設(shè)置權(quán)限
????????????//設(shè)置請求頭等
????????????//開啟連接
????????????//connection.connect();
????????????//讀取響應(yīng)
????????????if?(connection.getResponseCode()?==?200)?{
????????????????is?=?connection.getInputStream();
????????????????if?(null?!=?is)?{
????????????????????br?=?new?BufferedReader(new?InputStreamReader(is,?"GBK"));
????????????????????String?temp?=?null;
????????????????????while?(null?!=?(temp?=?br.readLine()))?{
????????????????????????result.append(temp);
????????????????????????result.append("
");
????????????????????}
????????????????}
????????????}
?
????????}?catch?(MalformedURLException?e)?{
????????????e.printStackTrace();
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}?finally?{
????????????//關(guān)閉連接
????????????if(br!=null){
????????????????try?{
????????????????????br.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????????if(os!=null){
????????????????try?{
????????????????????os.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????????if(is!=null){
????????????????try?{
????????????????????is.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????????//關(guān)閉連接
????????????connection.disconnect();
????????}
????????return?result.toString();
????}
?
????public?static?void?main(String[]?args)?{
????????String?message?=?doPost("https://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071",?"");
????????System.out.println(message);
????}
}

?

?

運行結(jié)果：

2.2 通過apache通用封裝好的HttpClient

httpClient的get或post請求方式步驟：

生成一個HttpClient對象并設(shè)置相應(yīng)的參數(shù)；

生成一個GetMethod對象或PostMethod并設(shè)置響應(yīng)的參數(shù)；

用HttpClient生成的對象來執(zhí)行GetMethod生成的Get方法；

處理響應(yīng)狀態(tài)碼；

如果正常響應(yīng)，處理HTTP響應(yīng)內(nèi)容；

釋放連接。

導(dǎo)入以下jar包：

?

?

 

????commons-httpclient
????commons-httpclient
????3.1

?
 

????com.alibaba
????fastjson
????1.2.32

?

?

代碼如下：

?

?

package?com.riemann.springbootdemo.util.common.httpConnectionUtil;
?
import?com.alibaba.fastjson.JSONObject;
import?org.apache.commons.httpclient.*;
import?org.apache.commons.httpclient.methods.GetMethod;
import?org.apache.commons.httpclient.methods.PostMethod;
import?org.apache.commons.httpclient.params.HttpMethodParams;
?
import?java.io.IOException;
?
/**
?*?@author?riemann
?*/
public?class?HttpClientUtil?{
????/**
?????*?httpClient的get請求方式
?????*?使用GetMethod來訪問一個URL對應(yīng)的網(wǎng)頁實現(xiàn)步驟：
?????*?1.生成一個HttpClient對象并設(shè)置相應(yīng)的參數(shù)；
?????*?2.生成一個GetMethod對象并設(shè)置響應(yīng)的參數(shù)；
?????*?3.用HttpClient生成的對象來執(zhí)行GetMethod生成的Get方法；
?????*?4.處理響應(yīng)狀態(tài)碼；
?????*?5.若響應(yīng)正常，處理HTTP響應(yīng)內(nèi)容；
?????*?6.釋放連接。
?????*?@param?url
?????*?@param?charset
?????*?@return
?????*/
????public?static?String?doGet(String?url,?String?charset)?{
????????//1.生成HttpClient對象并設(shè)置參數(shù)
????????HttpClient?httpClient?=?new?HttpClient();
????????//設(shè)置Http連接超時為5秒
????????httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(5000);
????????//2.生成GetMethod對象并設(shè)置參數(shù)
????????GetMethod?getMethod?=?new?GetMethod(url);
????????//設(shè)置get請求超時為5秒
????????getMethod.getParams().setParameter(HttpMethodParams.SO_TIMEOUT,?5000);
????????//設(shè)置請求重試處理，用的是默認(rèn)的重試處理：請求三次
????????getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,?new?DefaultHttpMethodRetryHandler());
????????String?response?=?"";
????????//3.執(zhí)行HTTP?GET?請求
????????try?{
????????????int?statusCode?=?httpClient.executeMethod(getMethod);
????????????//4.判斷訪問的狀態(tài)碼
????????????if?(statusCode?!=?HttpStatus.SC_OK)?{
????????????????System.err.println("請求出錯："?+?getMethod.getStatusLine());
????????????}
????????????//5.處理HTTP響應(yīng)內(nèi)容
????????????//HTTP響應(yīng)頭部信息，這里簡單打印
????????????Header[]?headers?=?getMethod.getResponseHeaders();
????????????for(Header?h?:?headers)?{
????????????????System.out.println(h.getName()?+?"---------------"?+?h.getValue());
????????????}
????????????//讀取HTTP響應(yīng)內(nèi)容，這里簡單打印網(wǎng)頁內(nèi)容
????????????//讀取為字節(jié)數(shù)組
????????????byte[]?responseBody?=?getMethod.getResponseBody();
????????????response?=?new?String(responseBody,?charset);
????????????System.out.println("-----------response:"?+?response);
????????????//讀取為InputStream，在網(wǎng)頁內(nèi)容數(shù)據(jù)量大時候推薦使用
????????????//InputStream?response?=?getMethod.getResponseBodyAsStream();
????????}?catch?(HttpException?e)?{
????????????//發(fā)生致命的異常，可能是協(xié)議不對或者返回的內(nèi)容有問題
????????????System.out.println("請檢查輸入的URL!");
????????????e.printStackTrace();
????????}?catch?(IOException?e)?{
????????????//發(fā)生網(wǎng)絡(luò)異常
????????????System.out.println("發(fā)生網(wǎng)絡(luò)異常!");
????????}?finally?{
????????????//6.釋放連接
????????????getMethod.releaseConnection();
????????}
????????return?response;
????}
?
????/**
?????*?post請求
?????*?@param?url
?????*?@param?json
?????*?@return
?????*/
????public?static?String?doPost(String?url,?JSONObject?json){
????????HttpClient?httpClient?=?new?HttpClient();
????????PostMethod?postMethod?=?new?PostMethod(url);
?
????????postMethod.addRequestHeader("accept",?"*/*");
????????postMethod.addRequestHeader("connection",?"Keep-Alive");
????????//設(shè)置json格式傳送
????????postMethod.addRequestHeader("Content-Type",?"application/json;charset=GBK");
????????//必須設(shè)置下面這個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");
????????//添加請求參數(shù)
????????postMethod.addParameter("commentId",?json.getString("commentId"));
?
????????String?res?=?"";
????????try?{
????????????int?code?=?httpClient.executeMethod(postMethod);
????????????if?(code?==?200){
????????????????res?=?postMethod.getResponseBodyAsString();
????????????????System.out.println(res);
????????????}
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}
????????return?res;
????}
?
????public?static?void?main(String[]?args)?{
????????System.out.println(doGet("http://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071",?"GBK"));
????????System.out.println("-----------分割線------------");
????????System.out.println("-----------分割線------------");
????????System.out.println("-----------分割線------------");
?
????????JSONObject?jsonObject?=?new?JSONObject();
????????jsonObject.put("commentId",?"13026194071");
????????System.out.println(doPost("http://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071",?jsonObject));
????}
}

?

?

運行結(jié)果：

post請求的jsonObject參數(shù)也成功寫入

2.3 通過Apache封裝好的CloseableHttpClient

CloseableHttpClient是在HttpClient的基礎(chǔ)上修改可以更新而來的，這里還涉及到請求頭的設(shè)置（請求），利用fastjson轉(zhuǎn)換請求或返回請求結(jié)果字符串為json格式，當(dāng)然方式也是設(shè)置頭token、 json的，這里只在下面說明。

導(dǎo)入以下jar包：

?

?

 

????org.apache.httpcomponents
????httpclient
????4.5.2

?
 

????com.alibaba
????fastjson
????1.2.32

?

?

代碼如下：

?

?

package?com.riemann.springbootdemo.util.common.httpConnectionUtil;
?
import?com.alibaba.fastjson.JSONObject;
import?org.apache.http.HttpResponse;
import?org.apache.http.HttpStatus;
import?org.apache.http.client.methods.CloseableHttpResponse;
import?org.apache.http.client.methods.HttpGet;
import?org.apache.http.client.methods.HttpPost;
import?org.apache.http.entity.StringEntity;
import?org.apache.http.impl.client.CloseableHttpClient;
import?org.apache.http.impl.client.HttpClientBuilder;
import?org.apache.http.util.EntityUtils;
?
import?java.io.IOException;
import?java.io.UnsupportedEncodingException;
?
/**
?*?@author?riemann
?*/
public?class?CloseableHttpClientUtil?{
?
????private?static?String?tokenString?=?"";
????private?static?String?AUTH_TOKEN_EXPIRED?=?"AUTH_TOKEN_EXPIRED";
????private?static?CloseableHttpClient?httpClient?=?null;
?
????/**
?????*?以get方式調(diào)用第三方接口
?????*?@param?url
?????*?@param?token
?????*?@return
?????*/
????public?static?String?doGet(String?url,?String?token)?{
????????//創(chuàng)建HttpClient對象
????????CloseableHttpClient?httpClient?=?HttpClientBuilder.create().build();
????????HttpGet?httpGet?=?new?HttpGet(url);
????????if?(null?!=?tokenString?&&?!tokenString.equals(""))?{
????????????tokenString?=?getToken();
????????}
????????//api_gateway_auth_token自定義header頭，用于token驗證使用
????????httpGet.addHeader("api_gateway_auth_token",tokenString);
????????httpGet.addHeader("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");
????????try?{
????????????HttpResponse?response?=?httpClient.execute(httpGet);
????????????if?(response.getStatusLine().getStatusCode()?==?HttpStatus.SC_OK)?{
????????????????//返回json格式
????????????????String?res?=?EntityUtils.toString(response.getEntity());
????????????????return?res;
????????????}
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}
????????return?null;
????}
?
????/**
?????*?以post方式調(diào)用第三方接口
?????*?@param?url
?????*?@param?json
?????*?@return
?????*/
????public?static?String?doPost(String?url,?JSONObject?json)?{
????????if?(null?==?httpClient)?{
????????????httpClient?=?HttpClientBuilder.create().build();
????????}
????????HttpPost?httpPost?=?new?HttpPost(url);
????????if?(null?!=?tokenString?&&?tokenString.equals(""))?{
????????????tokenString?=?getToken();
????????}
????????//api_gateway_auth_token自定義header頭，用于token驗證使用
????????httpPost.addHeader("api_gateway_auth_token",?tokenString);
????????httpPost.addHeader("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");
????????try?{
????????????StringEntity?se?=?new?StringEntity(json.toString());
????????????se.setContentEncoding("UTF-8");
????????????//發(fā)送json數(shù)據(jù)需要設(shè)置contentType
????????????se.setContentType("application/x-www-form-urlencoded");
????????????//設(shè)置請求參數(shù)
????????????httpPost.setEntity(se);
????????????HttpResponse?response?=?httpClient.execute(httpPost);
????????????if?(response.getStatusLine().getStatusCode()?==?HttpStatus.SC_OK)?{
????????????????//返回json格式
????????????????String?res?=?EntityUtils.toString(response.getEntity());
????????????????return?res;
????????????}
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}?finally?{
????????????if?(httpClient?!=?null){
????????????????try?{
????????????????????httpClient.close();
????????????????}?catch?(IOException?e)?{
????????????????????e.printStackTrace();
????????????????}
????????????}
????????}
????????return?null;
????}
?
????/**
?????*?獲取第三方接口的token
?????*/
????public?static?String?getToken()?{
????????String?token?=?"";
????????JSONObject?object?=?new?JSONObject();
????????object.put("appid",?"appid");
????????object.put("secretkey",?"secretkey");
????????if?(null?==?httpClient)?{
????????????httpClient?=?HttpClientBuilder.create().build();
????????}
????????HttpPost?httpPost?=?new?HttpPost("http://localhost/login");
????????httpPost.addHeader("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");
????????try?{
????????????StringEntity?se?=?new?StringEntity(object.toString());
????????????se.setContentEncoding("UTF-8");
????????????//發(fā)送json數(shù)據(jù)需要設(shè)置contentType
????????????se.setContentType("application/x-www-form-urlencoded");
????????????//設(shè)置請求參數(shù)
????????????httpPost.setEntity(se);
????????????HttpResponse?response?=?httpClient.execute(httpPost);
????????????//這里可以把返回的結(jié)果按照自定義的返回數(shù)據(jù)結(jié)果，把string轉(zhuǎn)換成自定義類
????????????//ResultTokenBO?result?=?JSONObject.parseObject(response,?ResultTokenBO.class);
????????????//把response轉(zhuǎn)為jsonObject
????????????JSONObject?result?=?(JSONObject)?JSONObject.parseObject(String.valueOf(response));
????????????if?(result.containsKey("token"))?{
????????????????token?=?result.getString("token");
????????????}
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}
????????return?token;
????}
?
????/**
?????*?測試
?????*/
????public?static?void?test(String?telephone)?{
?
????????JSONObject?object?=?new?JSONObject();
????????object.put("telephone",?telephone);
?
????????//首先獲取token
????????tokenString?=?getToken();
????????String?response?=?doPost("http://localhost/searchUrl",?object);
????????//如果返回的結(jié)果是list形式的，需要使用JSONObject.parseArray轉(zhuǎn)換
????????//List?list?=?JSONObject.parseArray(response,?Result.class);
????????System.out.println(response);
????}
?
????public?static?void?main(String[]?args)?{
????????test("12345678910");
????}
}

?

?

2.4 通過SpringBoot-RestTemplate

springBoot-RestTemple是這些代碼的集合的大成者，編寫簡單，目前可以采用的調(diào)用接口有：

delete() HTTP DELETE在特定操作的 URL 上對資源執(zhí)行

exchange() 在URL上執(zhí)行特定的HTTP方法，返回包含對象的ResponseEntity，這個對象是從請求體中映射到的

execute() 在上執(zhí)行特定的HTTP方法，返回一個從響應(yīng)體映射到的對象

get) 發(fā)送一個HTTP GET請求返回的ResponseEntity包含了響應(yīng)體，映射成的對象

getForObject() 發(fā)送HTTP GET請求，返回的請求體將映射為一個對象

postForEntity() POST 數(shù)據(jù)到一個URL，返回包含一個對象的ResponseEntity，這個對象是從響應(yīng)體中映射的

postForObject() POST 數(shù)據(jù)到一個 URL，返回根據(jù)響應(yīng)體形成的對象

headForHeaders() 發(fā)送HTTP HEAD請求，返回包含特定資源URL的HTTP頭

optionsForAllow() 發(fā)送HTTP OPTIONS請求，返回對特定URL的Allow頭信息

postForLocation() POST 數(shù)據(jù)到一個 URL，返回新創(chuàng)建資源的 URL

put() PUT 資源到特定的 URL

首先導(dǎo)入springboot的web包

?

?

????????org.springframework.boot
????????spring-boot-starter-parent
????????2.0.4.RELEASE
????
?
????
???????? 
????????
????????????org.apache.httpcomponents
????????????httpclient
????????????4.5.2
????????
?
???????? 
???????? 
????????
????????????org.springframework.boot
????????????spring-boot-configuration-processor
????????????true
????????
????????
????????????org.springframework.boot
????????????spring-boot-starter-aop
????????
????????
????????????org.springframework.boot
????????????spring-boot-starter-web
????????????
????????????????
????????????????????org.springframework.boot
????????????????????spring-boot-starter-tomcat
????????????????
????????????
????????
????????
????????????org.springframework.boot
????????????spring-boot-starter-jetty
????????
????????
????????????org.springframework.boot
????????????spring-boot-starter-test
????????????test
????????
????

?

?

在啟動類同包下創(chuàng)建RestTemplateConfig.java類

?

?

import?org.springframework.context.annotation.Bean;
import?org.springframework.context.annotation.Configuration;
import?org.springframework.http.client.ClientHttpRequestFactory;
import?org.springframework.http.client.SimpleClientHttpRequestFactory;
import?org.springframework.web.client.RestTemplate;
?
/**
?*?@author?riemann
?*/
@Configuration
public?class?RestTemplateConfig?{
?
????@Bean
????public?RestTemplate?restTemplate(ClientHttpRequestFactory?factory){
????????return?new?RestTemplate(factory);
????}
?
????@Bean
????public?ClientHttpRequestFactory?simpleClientHttpRequestFactory(){
????????SimpleClientHttpRequestFactory?factory?=?new?SimpleClientHttpRequestFactory();
????????factory.setConnectTimeout(15000);
????????factory.setReadTimeout(5000);
????????return?factory;
????}
}

?

?

然后在Service類（RestTemplateToInterface）中注入使用

具體代碼如下：

?

?

import?com.alibaba.fastjson.JSONObject;
import?com.swordfall.model.User;
import?org.springframework.beans.factory.annotation.Autowired;
import?org.springframework.http.*;
import?org.springframework.stereotype.Service;
import?org.springframework.web.client.RestTemplate;
?
/**
?*?@author?riemann
?*/
@Service
public?class?RestTemplateToInterface?{
?
????@Autowired
????private?RestTemplate?restTemplate;
?
????/**
?????*?以get方式請求第三方http接口?getForEntity
?????*?@param?url
?????*?@return
?????*/
????public?User?doGetWith1(String?url){
????????ResponseEntity?responseEntity?=?restTemplate.getForEntity(url,?User.class);
????????User?user?=?responseEntity.getBody();
????????return?user;
????}
?
????/**
?????*?以get方式請求第三方http接口?getForObject
?????*?返回值返回的是響應(yīng)體，省去了我們再去getBody()
?????*?@param?url
?????*?@return
?????*/
????public?User?doGetWith2(String?url){
????????User?user??=?restTemplate.getForObject(url,?User.class);
????????return?user;
????}
?
????/**
?????*?以post方式請求第三方http接口?postForEntity
?????*?@param?url
?????*?@return
?????*/
????public?String?doPostWith1(String?url){
????????User?user?=?new?User("小白",?20);
????????ResponseEntity?responseEntity?=?restTemplate.postForEntity(url,?user,?String.class);
????????String?body?=?responseEntity.getBody();
????????return?body;
????}
?
????/**
?????*?以post方式請求第三方http接口?postForEntity
?????*?@param?url
?????*?@return
?????*/
????public?String?doPostWith2(String?url){
????????User?user?=?new?User("小白",?20);
????????String?body?=?restTemplate.postForObject(url,?user,?String.class);
????????return?body;
????}
?
????/**
?????*?exchange
?????*?@return
?????*/
????public?String?doExchange(String?url,?Integer?age,?String?name){
????????//header參數(shù)
????????HttpHeaders?headers?=?new?HttpHeaders();
????????String?token?=?"asdfaf2322";
????????headers.add("authorization",?token);
????????headers.setContentType(MediaType.APPLICATION_JSON);
?
????????//放入body中的json參數(shù)
????????JSONObject?obj?=?new?JSONObject();
????????obj.put("age",?age);
????????obj.put("name",?name);
?
????????//組裝
????????HttpEntity?request?=?new?HttpEntity<>(obj,?headers);
????????ResponseEntity?responseEntity?=?restTemplate.exchange(url,?HttpMethod.POST,?request,?String.class);
????????String?body?=?responseEntity.getBody();
????????return?body;
????}
}

?

?

2.5 通過okhttp

現(xiàn)在也是蠻流行的，基于手機端很火的，這里分享一下OkHttpClient客戶端，業(yè)務(wù)代碼get、post請求直接調(diào)用http就好了。

pom文件引入依賴包

?

?

????com.squareup.okhttp3
????okhttp
????3.10.0

@Slf4j
public?class?OkHttpClient?{
????private?static?final?MediaType?JSON?=?MediaType.parse("application/json;?charset=utf-8");
?
????private?volatile?static?okhttp3.OkHttpClient?client;
?
????private?static?final?int?MAX_IDLE_CONNECTION?=?Integer
????????????.parseInt(ConfigManager.get("httpclient.max_idle_connection"));
?
????private?static?final?long?KEEP_ALIVE_DURATION?=?Long
????????????.parseLong(ConfigManager.get("httpclient.keep_alive_duration"));
?
????private?static?final?long?CONNECT_TIMEOUT?=?Long.parseLong(ConfigManager.get("httpclient.connectTimeout"));
?
????private?static?final?long?READ_TIMEOUT?=?Long.parseLong(ConfigManager.get("httpclient.?"));
?
????/**
?????*?單例模式(雙重檢查模式)?獲取類實例
?????*
?????*?@return?client
?????*/
????private?static?okhttp3.OkHttpClient?getInstance()?{
????????if?(client?==?null)?{
????????????synchronized?(okhttp3.OkHttpClient.class)?{
????????????????if?(client?==?null)?{
????????????????????client?=?new?okhttp3.OkHttpClient.Builder()
????????????????????????????.connectTimeout(CONNECT_TIMEOUT,?TimeUnit.SECONDS)
????????????????????????????.readTimeout(READ_TIMEOUT,?TimeUnit.SECONDS)
????????????????????????????.connectionPool(new?ConnectionPool(MAX_IDLE_CONNECTION,?KEEP_ALIVE_DURATION,
????????????????????????????????????TimeUnit.MINUTES))
????????????????????????????.build();
????????????????}
????????????}
????????}
????????return?client;
????}
?
????public?static?String?syncPost(String?url,?String?json)?throws?IOException?{
????????RequestBody?body?=?RequestBody.create(JSON,?json);
????????Request?request?=?new?Request.Builder()
????????????????.url(url)
????????????????.post(body)
????????????????.build();
????????try?{
????????????Response?response?=?OkHttpClient.getInstance().newCall(request).execute();
????????????if?(response.isSuccessful())?{
????????????????String?result?=?response.body().string();
????????????????log.info("syncPost?response?=?{},?responseBody=?{}",?response,?result);
????????????????return?result;
????????????}
????????????String?result?=?response.body().string();
????????????log.info("syncPost?response?=?{},?responseBody=?{}",?response,?result);
????????????throw?new?IOException("三方接口返回http狀態(tài)碼為"?+?response.code());
????????}?catch?(Exception?e)?{
????????????log.error("syncPost()?url:{}?have?a?ecxeption?{}",?url,?e);
????????????throw?new?RuntimeException("syncPost()?have?a?ecxeption?{}"?+?e.getMessage());
????????}
????}
?
????public?static?String?syncGet(String?url,?Map?headParamsMap)?throws?IOException?{
????????Request?request;
????????final?Request.Builder?builder?=?new?Request.Builder().url(url);
????????try?{
????????????if?(!CollectionUtils.isEmpty(headParamsMap))?{
????????????????final?Iterator>?iterator?=?headParamsMap.entrySet()
????????????????????????.iterator();
????????????????while?(iterator.hasNext())?{
????????????????????final?Map.Entry?entry?=?iterator.next();
????????????????????builder.addHeader(entry.getKey(),?(String)?entry.getValue());
????????????????}
????????????}
????????????request?=?builder.build();
????????????Response?response?=?OkHttpClient.getInstance().newCall(request).execute();
????????????String?result?=?response.body().string();
????????????log.info("syncGet?response?=?{},responseBody=?{}",?response,?result);
????????????if?(!response.isSuccessful())?{
????????????????throw?new?IOException("三方接口返回http狀態(tài)碼為"?+?response.code());
????????????}
????????????return?result;
????????}?catch?(Exception?e)?{
????????????log.error("remote?interface?url:{}?have?a?ecxeption?{}",?url,?e);
????????????throw?new?RuntimeException("三方接口返回異常");
????????}
????}
?
}

?

?

編輯：黃飛