Spring Boot中的策略

Z时代
2024-01-10
分类：问答

嗨，我在Spring

Boot应用程序中有一个策略模式。我所有的策略都有自动装配构造函数。我是Spring靴的新手。我没有最简单的想法，因为自动装配的构造函数已经注入了依赖性，因此我该如何为策略类编写工厂。感谢您为此提供的任何帮助。

我将省略Intefaces和基类，以免使样本混乱。

public class StrategyA implement Strategy {
private DependencyA depA;
private DependencyB depB;
   @Autowired
   public StragegyA(DependencyA depA, DependencyB depB) {
       this.depA = depA;
       this.depB = depB;
   }
}
public class StrategyB implements Strategy {
private DependencyA depA;
private DependencyB depB;
   @Autowired
   public StragegyB(DependencyA depA, DependencyB depB) {
       this.depA = depA;
       this.depB = depB;
   }
}
public class StrategyFactory {
    public Strategy getStrategy(String strategyName) {
      if (name.equals("StrategyA")) {
         <b>return StrategyA; //My problem is here
      } else {
         return StrategyB; // And Here
      }
    }
}

回答：

前面所有的答案都是使用Spring

DI的直接方法。但是，也可以使用ServiceLocatorFactoryBean来创建工厂，而不必在工厂中指定任何bean。首先为您的工厂定义一个接口：

public interface MyFactory {
    Strategy get(String type);
}
// Could be an abstract class
public interface Strategy {
    void doStuff();
}

然后在您的应用程序中：

@Configuration
public class AppConfiguration {
    @Autowired
    private BeanFactory beanFactory;
    public ServiceLocatorFactoryBean myFactoryLocator() {
        final ServiceLocatorFactoryBean locator = new ServiceLocatorFactoryBean();
        locator.setServiceLocatorInterface(MyFactory.class);
        locator.setBeanFactory(beanFactory);
        return locator;
    }
    @Bean
    public MyFactory myFactory() {
        final ServiceLocatorFactoryBean locator = myFactoryLocator();
        locator.afterPropertiesSet();
        return (MyFactory) locator.getObject();
    }
}