httpclient工具类（支持泛型转换）

1、网上搜到的httpclient工具类的问题：

1.1、如下图我们都能够发现这种封装的问题：

• 代码繁杂、充斥了很多重复性代码
• 返回值单一，无法拿到对应的Java Bean对象及List对象集合
• 实际场景中会对接大量第三方的OPEN API，下述方法的扩展性差

1.2、简洁调用方式演示

本文基于上述问题，通过设计模式、泛型、JSON工具类的方式进行了封装，得到了下述更方便、更简洁的http请求调用方式

Entity params = new Entity();
params.setUrl("/common/postJson");Map<String, Object> map = new HashMap<>();
map.put("userId", "13277887788");
map.put("companyId", "87037827534cf");
params.setParams(map);// 返回对象集合
List<AppEntity> appEntity = thirdHttpProcessorFactory.doGetReturnList(ThirdSystemEnum.ION, params, AppEntity.class);
// 返回String类型
String result = thirdHttpProcessorFactory.doGetReturnBean(ThirdSystemEnum.ION, params, String.class);
// 返回指定的对象
AppEntity appEntity = thirdHttpProcessorFactory.doGetReturnBean(ThirdSystemEnum.ION, params, AppEntity.class);

1.3、 目录结构

2、引入的maven仓库

 <dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.14.2</version>
</dependency>
<dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.7.16</version>
</dependency>

• ThirdHttpProcessorFactory：存储不同三方平台的处理期
• ThirdHttpProcessor：定义通用的接口
• AbstractThirdHttpProcessor：定义公共的处理逻辑
• IonHttpProcessor：定义各对接平台的差异性逻辑
• AppEntity：返回值
• Entity：入参
• ThirdSystemEnum：定义三方平台的枚举

3、代码实现

3.1、获取不同第三方处理器的工厂ThirdHttpProcessorFactory

package com.ionrocking.platform.tripartite;import com.ionrocking.common.core.exception.ServiceException;
import com.ionrocking.platform.tripartite.entity.Entity;
import com.ionrocking.platform.tripartite.enums.ThirdSystemEnum;
import lombok.experimental.Accessors;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;import javax.annotation.PostConstruct;
import java.util.HashMap;
import java.util.List;
import java.util.Map;/*** @author ke* Created by on  2023-10-27 15:23*/
@Component
@Accessors(chain = true)
public class ThirdHttpProcessorFactory {@Autowiredprivate List<ThirdHttpProcessor> thirdHttpProcessors;private Map<String, ThirdHttpProcessor> thirdHttpProcessorMap;@PostConstructpublic void init() {if (CollectionUtils.isEmpty(thirdHttpProcessors)) {return;}thirdHttpProcessorMap = new HashMap<>(8);for (ThirdHttpProcessor processor : thirdHttpProcessors) {thirdHttpProcessorMap.put(processor.getType().getCode(), processor);}}private ThirdHttpProcessor getThirdHttpProcessor(String type) {ThirdSystemEnum thirdSystemEnum = ThirdSystemEnum.getByCode(type);if (null == thirdSystemEnum) {throw new ServiceException("三方OpenApi尚未配置，无法进行请求");}return thirdHttpProcessorMap.get(type);}/*** http get请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return T              返回数据对象* @throws Exception 业务执行异常*/public <T> T doGetReturnBean(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doGetReturnBean(entity, tClass);}/*** http post请求，入参支持application/x-www-form-urlencoded 请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return T              返回数据对象* @throws Exception 业务执行异常*/public <T> T doPostReturnBean(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doPostReturnBean(entity, tClass);}/*** http post请求，入参支持application/json请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return T              返回数据对象* @throws Exception 业务执行异常*/public <T> T doPostJsonReturnBean(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doPostJsonReturnBean(entity, tClass);}/*** http get请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return List<T>        返回数据集合* @throws Exception 业务执行异常*/public <T> List<T> doGetReturnList(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doGetReturnList(entity, tClass);}/*** http post请求，入参支持application/x-www-form-urlencoded 请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return List<T>        返回数据集合* @throws Exception 业务执行异常*/public <T> List<T> doPostReturnList(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doPostReturnList(entity, tClass);}/*** http post请求，入参支持application/json请求** @param thirdSystemEnum 三方系统类型枚举* @param entity          参数* @param tClass          返回参数类型* @return List<T>        返回数据集合* @throws Exception 业务执行异常*/public <T> List<T> doPostJsonReturnList(ThirdSystemEnum thirdSystemEnum, Entity entity, Class<T> tClass) throws Exception {return getThirdHttpProcessor(thirdSystemEnum.getCode()).doPostJsonReturnList(entity, tClass);}}

3.2、http请求处理的接口ThirdHttpProcessor

/*** Dans.com Inc.* Copyright (c) 2011-2020 All Rights Reserved*/
package com.ionrocking.platform.tripartite;import com.ionrocking.platform.tripartite.entity.Entity;
import com.ionrocking.platform.tripartite.enums.ThirdSystemEnum;import java.util.List;/*** 追踪事件处理器** @author ke* Created by on  2023-06-20 15:23*/
public interface ThirdHttpProcessor {/*** 业务执行** @param entity* @param tClass* @return T* @throws Exception 业务执行异常*/<T> T doGetReturnBean(Entity entity, Class<T> tClass) throws Exception;/*** 业务执行** @param entity* @param tClass* @return* @throws Exception 业务执行异常*/<T> T doPostReturnBean(Entity entity, Class<T> tClass) throws Exception;/*** 业务执行** @param entity* @param tClass* @return* @throws Exception 业务执行异常*/<T> T doPostJsonReturnBean(Entity entity, Class<T> tClass) throws Exception;/*** 业务执行** @param entity* @param tClass* @return T* @throws Exception 业务执行异常*/<T> List<T> doGetReturnList(Entity entity, Class<T> tClass) throws Exception;/*** 业务执行** @param entity* @param tClass* @return* @throws Exception 业务执行异常*/<T> List<T> doPostReturnList(Entity entity, Class<T> tClass) throws Exception;/*** 业务执行** @param entity* @param tClass* @return* @throws Exception 业务执行异常*/<T> List<T> doPostJsonReturnList(Entity entity, Class<T> tClass) throws Exception;/*** 获取事件类型** @return*/ThirdSystemEnum getType();
}

3.3、通用逻辑处理的抽象类AbstractThirdHttpProcessor

• 如在通过http client发起HTTP请求时，除了请求头requestHeader、请求入参requestBody不同，其他逻辑都是一样的，则可以进行公共代码的抽取
• 如果存在特殊的逻辑处理，则可以在子类中重写父类的方法

package com.ionrocking.platform.tripartite;import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.text.CharSequenceUtil;
import cn.hutool.http.HttpUtil;
import cn.hutool.json.JSONUtil;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.ionrocking.common.core.exception.ServiceException;
import com.ionrocking.platform.config.SysNacosConfig;
import com.ionrocking.platform.tripartite.entity.Entity;
import com.ionrocking.platform.tripartite.entity.IonResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;/*** @author ke* @Date 2023/10/27*/
@Slf4j
@Component
public abstract class AbstractThirdHttpProcessor implements ThirdHttpProcessor {@Overridepublic <T> List<T> doGetReturnList(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createGet(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).form(requestBody).execute().body();return toList(result, tClass);}@Overridepublic <T> List<T> doPostReturnList(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createPost(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).form(requestBody).execute().body();return toList(result, tClass);}@Overridepublic <T> List<T> doPostJsonReturnList(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createPost(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).body(JSONUtil.toJsonStr(requestBody)).execute().body();return toList(result, tClass);}public <T> T toBean(String result, Class<T> tClass) throws Exception {ObjectMapper objectMapper = new ObjectMapper();IonResponse<Object> response = JSONUtil.toBean(result, IonResponse.class);if (CODE != response.getCode()) {throw new ServiceException(response.getMsg());}if (null == response.getData()) {return null;}return objectMapper.readValue(response.getData().toString(), tClass);}public <T> List<T> toList(String result, Class<T> tClass) throws JsonProcessingException {List<T> data = new ArrayList<>();IonResponse<List<Object>> response = JSONUtil.toBean(result, IonResponse.class);if (CODE != response.getCode()) {throw new ServiceException(response.getMsg());}if (CollUtil.isEmpty(response.getData())) {return null;}for (Object o : response.getData()) {ObjectMapper objectMapper = new ObjectMapper();data.add(objectMapper.readValue(o.toString(), tClass));}return data;}@Resourceprotected SysNacosConfig sysNacosConfig;protected static final int CODE = 200;@Overridepublic <T> T doGetReturnBean(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createGet(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).form(requestBody).execute().body();return toBean(result, tClass);}/*** 执行** @return*/@Overridepublic <T> T doPostReturnBean(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createPost(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).form(requestBody).execute().body();return toBean(result, tClass);}@Overridepublic <T> T doPostJsonReturnBean(Entity entity, Class<T> tClass) throws Exception {// 构造请求头Map<String, String> requestHead = constructRequestHead(entity);// 构造请求数据Map<String, Object> requestBody = constructRequestBody(entity);String result = HttpUtil.createPost(sysNacosConfig.getIonRequestUrl() + entity.getUrl()).addHeaders(requestHead).body(JSONUtil.toJsonStr(requestBody)).execute().body();return toBean(result, tClass);}/*** 构造请求头** @param entity* @return*/public abstract Map<String, String> constructRequestHead(Entity entity);/*** 构造请求体** @param entity* @return*/public Map<String, Object> constructRequestBody(Entity entity) {if (CharSequenceUtil.isBlank(entity.getUrl())) {throw new ServiceException("请求路径不能为空");}if (null == entity) {return null;}return entity.getParams();}}

3.4、第三方非通用逻辑处理类IonHttpProcessor

• 比如此处对接的xx公司需要进行access_token获取及验证，然后将access_token放在请求头中

package com.ionrocking.platform.tripartite.impl;import cn.hutool.core.lang.TypeReference;
import cn.hutool.core.text.CharSequenceUtil;
import cn.hutool.http.HttpUtil;
import cn.hutool.json.JSONUtil;
import com.ionrocking.platform.tripartite.AbstractThirdHttpProcessor;
import com.ionrocking.platform.tripartite.entity.Entity;
import com.ionrocking.platform.tripartite.entity.IonResponse;
import com.ionrocking.platform.tripartite.enums.ThirdSystemEnum;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;import java.util.HashMap;
import java.util.Map;/*** @author ke* @Date 2023/10/27*/
@Slf4j
@Component
public class IonHttpProcessor extends AbstractThirdHttpProcessor {private String accessTokenUrl = "/token/getAccessToken";private static final String ACCESS_TOKEN_KEY = "access_token";@Overridepublic Map<String, String> constructRequestHead(Entity entity) {Map<String, String> header = new HashMap<>(2);Map<String, Object> params = new HashMap<>(4);params.put("appId", sysNacosConfig.getIonRequestAppId());params.put("appSecret", sysNacosConfig.getIonRequestAppSecret());String result = HttpUtil.get(sysNacosConfig.getIonRequestUrl() + accessTokenUrl, params);if (CharSequenceUtil.isEmpty(result)) {return null;}TypeReference<IonResponse<Map<String, Object>>> typeRef = new TypeReference<IonResponse<Map<String, Object>>>() {};IonResponse<Map<String, Object>> response = JSONUtil.toBean(result, typeRef, false);if (CODE == response.getCode() && null != response.getData()) {if (response.getData().containsKey(ACCESS_TOKEN_KEY)) {header.put(ACCESS_TOKEN_KEY, response.getData().get(ACCESS_TOKEN_KEY).toString());}}return header;}@Overridepublic ThirdSystemEnum getType() {return ThirdSystemEnum.ION;}
}

3.5、枚举类ThirdSystemEnum

• 区分不同的平台，根据枚举获取不同的实现类

package com.ionrocking.platform.tripartite.enums;import org.apache.commons.lang3.StringUtils;/*** @author ke* @Date 2023/10/27*/
public enum ThirdSystemEnum {/*** XX科技公司*/ION("ion", "xx科技");private final String code;private final String name;public String getName() {return this.name;}public String getCode() {return this.code;}ThirdSystemEnum(String code, String name) {this.code = code;this.name = name;}public static ThirdSystemEnum getByCode(String code) {if (StringUtils.isEmpty(code)) {return null;}for (ThirdSystemEnum codeEnum : values()) {if (code.equals(codeEnum.getCode())) {return codeEnum;}}return null;}
}

3.6、第三方返回格式对象IonResponse

package com.ionrocking.platform.tripartite.entity;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;import java.io.Serializable;/*** @author ke* @Date 2023/10/27*/
@Data
@NoArgsConstructor
@AllArgsConstructor
public class IonResponse<T> implements Serializable {private static final long serialVersionUID = -8741972144218822267L;private int code;/*** 消息*/private String msg;/*** 数据*/private T data;/*** 总记录数*/private long total;
}

3.7、处理器入参对象Entity

• 此处定义请求的URL和请求的参数

package com.ionrocking.platform.tripartite.entity;import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;import java.io.Serializable;
import java.util.Map;/*** @author ke* @Date 2023/10/27*/
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class Entity implements Serializable {private static final long serialVersionUID = -6083780287057302816L;private String url;/*** 参数*/private Map<String, Object> params;
}

3.8、第三方接口返回值对象AppEntity

package com.ionrocking.platform.tripartite.entity;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.Accessors;import javax.validation.constraints.NotBlank;/*** @author ke* @Date 2023/10/26*/@Data
@Accessors(chain = true)
@NoArgsConstructor
@AllArgsConstructor
public class AppEntity {private long id;private String appId;@NotBlank(message = "应用名称不能为空")private String appName;private String appSecret;private String accessToken;private Integer isFlag;
}

3.9、Nacos配置

• Nacos中一般存放一些第三方的请求域名、鉴权的appId、appSecret等

tripartite-platform:ion:request:url: http://localhost:8080/api/appId: YodeqWwpappSecret: 87037827534cf848a570fae3c93a2469fa0262935af531dddfe7a52ae7f98f41

package com.ionrocking.platform.config;import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;/*** nacos配置信息* @author ke* @Date 2023/9/20*/
@Component
public class SysNacosConfig {@Value("${upload.path}")private String uploadPath;@Value("${tripartite-platform.ion.request.url}")private String ionRequestUrl;@Value("${tripartite-platform.ion.request.appId}")private String ionRequestAppId;@Value("${tripartite-platform.ion.request.appSecret}")private String ionRequestAppSecret;public String getUploadPath() {return uploadPath;}public String getIonRequestUrl() {return ionRequestUrl;}public String getIonRequestAppId() {return ionRequestAppId;}public String getIonRequestAppSecret() {return ionRequestAppSecret;}
}

测试

@RestController
@RequestMapping("/test")
public class Test {@Resourceprivate SysNacosConfig sysNacosConfig;@Resourceprivate ThirdHttpProcessorFactory thirdHttpProcessorFactory;@ResponseBody@RequestMapping(value = "/get")public AjaxResult get() throws Exception extends BaseController  {Entity params = new Entity();params.setUrl("/common/get");String result = thirdHttpProcessorFactory.doGetReturnBean(ThirdSystemEnum.ION, params, String.class);return AjaxResult.success(result);}@ResponseBody@RequestMapping(value = "/list")public AjaxResult list() throws Exception {Entity params = new Entity();params.setUrl("/common/list");List<AppEntity> appEntity = thirdHttpProcessorFactory.doGetReturnList(ThirdSystemEnum.ION, params, AppEntity.class);return AjaxResult.success(appEntity);}@ResponseBody@RequestMapping(value = "/postJson")public AjaxResult postJson() throws Exception {Entity params = new Entity();params.setUrl("/common/postJson");Map<String, Object> map = new HashMap<>();map.put("appId", "YodeqWwp");map.put("appSecret", "87037827534cf848a570fae3c93a2469fa0262935af531dddfe7a52ae7f98f41");params.setParams(map);List<AppEntity> list = thirdHttpProcessorFactory.doPostJsonReturnList(ThirdSystemEnum.ION, params, AppEntity.class);return AjaxResult.success(list);}
}