应用场景：存在银行卡和社保卡的支付、退货等接口，接口报文中使用transWay表示银行卡（0）和社保卡（1），transType表示支付（1）、退货（2）。那么由其组合便能出现四个逻辑，所以要实现动态的逻辑分发。
domain
@Data
public class PosApiReq {/** 交易方式 **/private String transWay;/** 交易类型 **/private String transType;
}
service
- 接口定义
public interface ICommonService {public Object handler(String json);
}
- 银行卡消费
@Service
@CodeType("01")
public class BankConsumService implements ICommonService{@Overridepublic Object handler(String json) {System.out.println("银行卡消费开始：" + json);return "bank-consum";}
}
- 银行卡退货
@Service
@CodeType("02")
public class BankRefundService implements ICommonService{@Overridepublic Object handler(String json) {System.out.println("银行卡退货开始：" + json);return "bank-refund";}
}
- 社保卡消费
@Service
@CodeType("11")
public class SocConsumService implements ICommonService{@Overridepublic Object handler(String json) {System.out.println("社保卡消费开始：" + json);return "soc-consum";}
}
- 社保卡退货
@Service
@CodeType("12")
public class SocRefundService implements ICommonService{@Overridepublic Object handler(String json) {System.out.println("社保卡退货开始：" + json);return "soc-refund";}
}
controller
@RestController
public class ServerController {private final Map<String, ICommonService> handlerMap = new HashMap<>();@Autowiredprivate void setHandler(List<ICommonService> commonServiceList) {for (ICommonService commonService : commonServiceList) {handlerMap.put(commonService.getClass().getAnnotation(CodeType.class).value(), commonService);}}@Anonymous@RequestMapping("/api")public Object api(@RequestBody PosApiReq posApiReq) {String transWay = posApiReq.getTransWay();String transType = posApiReq.getTransType();// 01 银行卡消费、02银行卡退货、11 社保卡消费、 12社保卡退货String value = transWay+transType;ICommonService commonService = handlerMap.get(value);Object object = commonService.handler(posApiReq.toString());return object;}
}
annotation
@Target(value={ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface CodeType {String value();
}
此方式完美的解决了根据不通交易调用不通逻辑的问题，如果新添加一类交易，只需要扩展实现ICommonService 接口的新类就可以。
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