需求背景

1、在管控流程中，涉及到的业务操作很多，不同的业务具有不同的策略实现
举个具体的例子：
在比价管控流程中，有比价策略和管控策略，每个业务的比价和管控均不一样。因此使用策略模式来开发

整体架构流程

1、定义业务策略枚举： 比价 和 管控

/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:33**/
public enum StrategyType {priceCompare,priceControl;
}

2、定义业务策略注解，标注出 策略的类

/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:34**/
@Retention(value = RetentionPolicy.RUNTIME)
@Target(value = ElementType.TYPE)
@Component
@Inherited
public @interface StrategyAnnotation {/*** 策略类型*/StrategyType[] strategyType();/*** 具体的策略建*/String[] dataType() default {};
}

3、定义策略基本方法

/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:46**/
public interface PriceCompareStrategy {/*** 执行价格比价*/public String doPriceCompare();
}/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:52**/
public interface PriceControlStrategy {/*** 执行管控* @return*/public String doPriceControl();
}

4、写每个具体实现的策略类

/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:44**/
@Service
@StrategyAnnotation(strategyType = StrategyType.priceCompare, dataType = "firstPriceCompare")
public class FirstPriceCompareStrategy implements PriceCompareStrategy {@Overridepublic String doPriceCompare() {System.out.println("-------first price compare start---------");System.out.println("-------do do do ---------");System.out.println("-------first price compare end---------");return "first price compare end";}
}/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:50**/
@Service
@StrategyAnnotation(strategyType = StrategyType.priceCompare, dataType = "secondPriceCompare")
public class SecondPriceCompareStrategy implements PriceCompareStrategy {@Overridepublic String doPriceCompare() {System.out.println("-------second price compare start---------");System.out.println("-------do do do ---------");System.out.println("-------second price compare end---------");return "second price compare end";}
}

/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:53**/
@Service
@StrategyAnnotation(strategyType = StrategyType.priceControl, dataType = "firstPriceControl")
public class FirstPriceControlStrategy implements PriceControlStrategy {@Overridepublic String doPriceControl() {System.out.println("---------do first price control start ---------------");System.out.println("---------do first price control end ---------------");return "do first price control end";}
}/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:53**/
@Service
@StrategyAnnotation(strategyType = StrategyType.priceControl, dataType = "secondPriceControl")
public class SecondPriceControlStrategy implements PriceControlStrategy {@Overridepublic String doPriceControl() {System.out.println("---------do second price control start ---------------");System.out.println("---------do second price control end ---------------");return "do second price control start";}
}@Service
@StrategyAnnotation(strategyType = {StrategyType.priceCompare, StrategyType.priceControl}, dataType = "commonStrategy")
public class PriceCompareAndControlStrategy implements PriceCompareStrategy, PriceControlStrategy {@Overridepublic String doPriceCompare() {System.out.println("-------common price compare start---------------");System.out.println("-------common price compare end---------------");return "common price compare end";}@Overridepublic String doPriceControl() {System.out.println("-------common price control start---------------");System.out.println("-------common price control end---------------");return "common price control end";}
}

5、编写策略管理类，管理所有的策略，并且对外暴露出 拿到具体策略类的方法

package com.dgut.strategy.springboot_strategy;import com.google.common.collect.Maps;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Service;import javax.annotation.PostConstruct;
import java.util.Map;/*** @description:* @author: hongbin.zheng* @create: 2023-07-17 16:59**/
@Service
public class StrategyServiceManager {@Autowiredprivate ApplicationContext context;/*** 存储策略:类型：具体实现类*/private Map<StrategyType, Map<String, Object>> map;public <E> E getStrategyInstance(StrategyType strategyType, String type, Class<E> eClass) {Map<String, Object> strategyTypeMap = map.get(strategyType);if (strategyTypeMap != null && !map.isEmpty()) {Object bean = strategyTypeMap.get(type);if (bean != null) {return eClass.cast(bean);}}return null;}@PostConstructprivate void init() {map = Maps.newHashMap();Map<String, Object> beans = context.getBeansWithAnnotation(StrategyAnnotation.class);for (Object value : beans.values()) {StrategyAnnotation annotation = value.getClass().getAnnotation(StrategyAnnotation.class);StrategyType[] strategyTypes = annotation.strategyType();String[] dataTypes = annotation.dataType();if (strategyTypes == null || strategyTypes.length == 0 || dataTypes == null || dataTypes.length == 0) {throw new RuntimeException("注解上必填字段不能为空");}for (StrategyType strategyType : strategyTypes) {for (String dataType : dataTypes) {map.computeIfAbsent(strategyType, k -> Maps.newHashMap()).put(dataType, value);}}}}}

6、代码流程测试

package com.dgut.strategy.springboot_strategy;import com.dgut.strategy.springboot_strategy.compare.PriceCompareStrategy;
import com.dgut.strategy.springboot_strategy.control.PriceControlStrategy;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;/*** @description:* @author: hongbin.zheng* @create: 2023-07-18 16:17**/
@SpringBootTest
public class StrategyTest {@Autowiredprivate StrategyServiceManager strategyServiceManager;@Testpublic void test2() {String strategyName = "priceControl";String dataType = "firstPriceControl";System.out.println(priceControlTest(strategyName, dataType));String dataType2 = "secondPriceControl";System.out.println(priceControlTest(strategyName, dataType2));String dataType3 = "commonStrategy";System.out.println(priceControlTest(strategyName, dataType3));}public String priceControlTest(String strategyName, String dataType) {StrategyType strategyType = StrategyType.valueOf(strategyName);if (strategyType == null) {return "管控策略不存在";}PriceControlStrategy strategyInstance = strategyServiceManager.getStrategyInstance(strategyType, dataType, PriceControlStrategy.class);if (strategyInstance == null) {return "找不到管控策略";}return strategyInstance.doPriceControl();}@Testpublic void test() {String strategyName = "priceCompare";String dataType = "firstPriceCompare";System.out.println(priceCompareTest(strategyName, dataType));String dataType2 = "secondPriceCompare";System.out.println(priceCompareTest(strategyName, dataType2));String dataType3 = "commonStrategy";System.out.println(priceCompareTest(strategyName, dataType3));}public String priceCompareTest(String strategyName, String dataType) {StrategyType strategyType = StrategyType.valueOf(strategyName);if (strategyType == null) {return "策略不存在";}PriceCompareStrategy strategyInstance = strategyServiceManager.getStrategyInstance(strategyType, dataType, PriceCompareStrategy.class);if (strategyInstance == null) {return "找不到比价策略";}return strategyInstance.doPriceCompare();}
}

技术细节

通过spring的context对象，解析获取类注解，拿到bean，常规操作，这个要学起来，很多地方可以这样子操作呢。

总结

$知道的越多，不知道的越多，希望对你有帮助！$