spring - 在spring配置文件中设置资源

Question

我正在尝试在 Spring 配置中配置推土机。当使用 xml 配置时，它会像

<bean class="org.dozer.spring.DozerBeanMapperFactoryBean">
    <property name="mappingFiles" value="classpath*:dozer/**/*.dzr.xml"/>
</bean>

如何在配置文件中定义资源。我尝试使用 ctx.getResource() ，但无法访问配置类中的 ApplicationContext 。

我尝试了 ContextRefreshedEvent 并从那里添加资源，但仍然没有运气。 (afterPropertiesSet 已被调用，添加的映射将不起作用)

public class ContextRefreshedEventBuilder extends ContextRefreshedEvent {
public ContextRefreshedEventBuilder(ApplicationContext ctx) {
    super(ctx);
    DozerBeanMapperFactoryBean mapper = ctx.getBean(DozerBeanMapperFactoryBean.class);
    try {
        mapper.setMappingFiles(ctx.getResources("classpath*:dozer/**/*.dzr.xml"));
    } catch (IOException e) {
        e.printStackTrace();
    }
}
}

也尝试使用ClassPathResource但找不到正确的方法

DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
mapper.setMappingFiles(new Resource[]{new ClassPathResource("classpath*:dozer/**/*.dzr.xml")});
return mapper;

如何添加 ClassPathResource 作为映射位置？

---答案---

@Bean
public DozerBeanMapperFactoryBean configDozer() throws IOException {
    DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
    Resource[] resources = new PathMatchingResourcePatternResolver().getResources("classpath*:dozer/**/*.dzr.xml");
    mapper.setMappingFiles(resources);
    return mapper;
}

Answer 1

您需要使用ResourcePatternResolver将 classpath*:dozer/**/*.dzr.xml 转换为 Resource[]。您可以使用 2 个主要选项。

1. 将 ApplicationContext 注入(inject)到您的配置类中，将其转换为 ResourcePatternResolver 并使用 getResources 方法。 Al Spring 默认应用程序上下文实现实现了 ResourcePatternResolver 接口(interface)。
2. 创建一个带有或不带有前面提到的上下文的 PathMatchingResourcePatternResolver。
3. 使用ResourcePatternUtils带有注入(inject)的 ResourceLoader。

使用 ResourcePatternUtils

@Configuration
public class MyConfiguration {

    @Autowired
    private ResourceLoader resourceLoader;

    public DozerBeanMapperFactoryBean mapper() throws IOException {
        DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
        // ResourceLoader is allowed to be null when using the ResourceLoaderUtils.
        ResourcePatternResolver resolver = ResourceLoaderUtils.getResourcePatternResolver(resourceLoader);
        Resource[] mappingFiles = resolver.getResources("classpath*:dozer/**/*.dzr.xml");
        mapper.setMappingFiles(mappingFiles);
        return mapper;
    }
}

最后一种方法的优点是您不依赖于 PathMatchingResourcePatternResolver，而只依赖于接口(interface)。实用程序类根据注入(inject)的 ResourceLoader 确定其功能。人们应该更喜欢这种加载资源的方式。

使用ApplicationContext

@Configuration
public class MyConfiguration {

    @Autowired
    private ApplicationContext context;

    public DozerBeanMapperFactoryBean mapper() throws IOException {
        DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
        Resource[] mappingFiles = ((ResourcePatternResolver) context).getResources("classpath*:dozer/**/*.dzr.xml");
        mapper.setMappingFiles(mappingFiles);
        return mapper;
    }
}

使用 PathMatchingResourcePatternResolver

@Configuration
public class MyConfiguration {

    private PathMatchingPatternResolver resolver = new PathMatchingPatternResolver();

    public DozerBeanMapperFactoryBean mapper() throws IOException {
        DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
        Resource[] mappingFiles = resolver.getResources("classpath*:dozer/**/*.dzr.xml");
        mapper.setMappingFiles(mappingFiles);
        return mapper;
    }
}

或者，如果您想重用现有的 ResourceLoader 稍有不同的版本:

@Configuration
public class MyConfiguration {

    @Autowired
    private ResourceLoader resourceLoader;

    public DozerBeanMapperFactoryBean mapper() throws IOException {
        DozerBeanMapperFactoryBean mapper = new DozerBeanMapperFactoryBean();
        Resource[] mappingFiles = new PathMatchingPatternResolver(resourceLoader).getResources("classpath*:dozer/**/*.dzr.xml");
        mapper.setMappingFiles(mappingFiles);
        return mapper;
    }
}