在对接支付宝过程中，发现支付宝每个接口例子，都定义了AlipayClient和xxxRequest、xxxResponse。
老的写法就是每次都去写new一个AlipayClient
package com.jws.smilepay.service;import com.alipay.api.AlipayApiException;import com.alipay.api.AlipayClient;import com.alipay.api.DefaultAlipayClient;import com.alipay.api.request.AlipaySystemOauthTokenRequest;import com.alipay.api.request.AlipayUserInfoShareRequest;import com.alipay.api.response.AlipaySystemOauthTokenResponse;import com.alipay.api.response.AlipayUserInfoShareResponse;/*** @author liuyg* @date 09月01日 14:09*/public class dome {private static String url = "/gateway.do";//应用idprivate static String appid = "app_id";//应用私钥private static String private_key = "your private_key";//支付宝公钥private static String alipay_public_key = "your alipay_public_key";/** * @Author liuyg* @Description 换取授权访问令牌* @Date /9/1 14:10*/public void oauthToken() {AlipayClient alipayClient = new DefaultAlipayClient(url,appid,private_key,"json","GBK",alipay_public_key,"RSA2");AlipaySystemOauthTokenRequest request = new AlipaySystemOauthTokenRequest();request.setGrantType("authorization_code");request.setCode("4b203fe6c11548bcabd8da5bb087a83b");request.setRefreshToken("08134b203fe6c11548bcabd8da5bb087a83b");AlipaySystemOauthTokenResponse response = null;try {response = alipayClient.execute(request);} catch (AlipayApiException e) {throw new RuntimeException(e);}if(response.isSuccess()){System.out.println("调用成功");} else {System.out.println("调用失败");}}/** * @Author liuyg* @Description 支付宝会员授权信息查询接口 * @Date /9/1 14:18 * @Param accessToken */public void infoShare(String accessToken){AlipayClient alipayClient = new DefaultAlipayClient(url,appid,private_key,"json","GBK",alipay_public_key,"RSA2");AlipayUserInfoShareRequest request = new AlipayUserInfoShareRequest();AlipayUserInfoShareResponse response = null;try {response = alipayClient.execute(request,accessToken);} catch (AlipayApiException e) {throw new RuntimeException(e);}if(response.isSuccess()){System.out.println("调用成功");} else {System.out.println("调用失败");}}}
后来发现，调用什么接口要根据入参和返参来定义。所以不需要每个接口都写入这么多的AlipayClient，我们可以把AlipayClient统一封装，只需要定义xxxRequest、xxxResponse即可。
改造后，可以做一些日志记录，数据处理等等。一个调用方法也可以缩减到最少3行的程度！
改造后代码如下：
package com.jws.smilepay.service;import com.alibaba.fastjson.JSONObject;import com.alipay.api.*;import com.alipay.api.request.AlipaySystemOauthTokenRequest;import com.alipay.api.request.AlipayUserInfoShareRequest;import com.alipay.api.response.AlipaySystemOauthTokenResponse;import com.alipay.api.response.AlipayUserInfoShareResponse;import mons.lang3.StringUtils;import org.slf4j.Logger;import org.slf4j.LoggerFactory;/*** @author liuyg* @date 09月01日 14:09*/public class dome {private Logger log = LoggerFactory.getLogger(getClass());private static String url = "/gateway.do";//应用idprivate static String appid = "app_id";//应用私钥private static String private_key = "your private_key";//支付宝公钥private static String alipay_public_key = "your alipay_public_key";/*** @Author liuyg* @Description 换取授权访问令牌* @Date /9/1 14:10*/public void oauthToken() {AlipaySystemOauthTokenRequest request = new AlipaySystemOauthTokenRequest();request.setGrantType("authorization_code");request.setCode("4b203fe6c11548bcabd8da5bb087a83b");request.setRefreshToken("08134b203fe6c11548bcabd8da5bb087a83b");AlipaySystemOauthTokenResponse response = new AlipaySystemOauthTokenResponse();response = (AlipaySystemOauthTokenResponse) postAli(request, response, null);}/*** @Author liuyg* @Description 支付宝会员授权信息查询接口* @Date /9/1 14:18* @Param accessToken*/public void infoShare(String accessToken) {AlipayUserInfoShareRequest request = new AlipayUserInfoShareRequest();AlipayUserInfoShareResponse response = new AlipayUserInfoShareResponse();response = (AlipayUserInfoShareResponse) postAli(request, response, accessToken);}/*** @Author liuyg* @Description 支付宝开放平台统一调用接口* @Date /9/1 14:23* @Param request* @Param response* @Param accessToken* @Return com.alipay.api.AlipayResponse*/public AlipayResponse postAli(AlipayRequest request, AlipayResponse response, String accessToken) {long startTime = 0;long endTime = 0;AlipayClient alipayClient = new DefaultAlipayClient(url, appid, private_key, "json", "GBK", alipay_public_key, "RSA2");try {log.info("支付宝请求参数：{}", JSONObject.toJSONString(request));startTime = System.currentTimeMillis();if (StringUtils.isNotBlank(accessToken)) {response = alipayClient.execute(request, accessToken);} else {response = alipayClient.execute(request);}endTime = System.currentTimeMillis();log.info("请求耗时：{},支付宝请求返回参数：{}", endTime - startTime, JSONObject.toJSONString(response));} catch (AlipayApiException e) {log.error("支付宝请求异常：", e);} catch (Exception e) {log.error("发送请求异常，请检查url地址是否正确，网络是否畅通！", e);}return response;}}
原文地址：支付宝开放平台api接口封装统一调用方式 - JavaLYG
