@PropertySource是否可以用於具有@Value的屬性？

Question

我正在創建一個新項目，並嘗試使用Java config，而以前使用XML config。 我的應用程序需要類似<property-placeholder>配置。 我有如下配置：

@Configuration
@PropertySources({
    @PropertySource(ignoreResourceNotFound = true,
                    value = "classpath:app.config.properties"),
    @PropertySource(ignoreResourceNotFound = true,
                    value = "classpath:app.user.config.properties"),
    @PropertySource(ignoreResourceNotFound = true,
                    value = "file:///${app.config}")
})
public class TestConfig {

    @Autowired
    Environment env;

    @Value("${prop1}")
    String prop1;

    @Bean
    public BasicData bd1() {
        System.out.println(env.getProperty("prop1"));
        System.out.println(prop1);
        return new BasicData("Test");
    }

env.getProperty(String)可以正常工作，盡管我雖然@Value注釋也可能起作用。

該配置通過MVC初始化程序實例化，如下所示：

public class AppInitializer
        extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[]{
            RootConfig.class,
            TestConfig.class,
            SecurityConfig.class
        };
    }

以前，我將使用以下內容通過XML配置實現此目的：

<context:property-placeholder
    location="classpath:app.config.properties,classpath:app.user.config.properties,file:///${app.config}"
    ignore-resource-not-found="true"/>

Answer 1

@PropertySource的文檔說，屬性源已添加到Environment 。

* Annotation providing a convenient and declarative mechanism for adding a
 * {@link org.springframework.core.env.PropertySource PropertySource} to Spring's
 * {@link org.springframework.core.env.Environment Environment}. To be used in
 * conjunction with @{@link Configuration} classes.

占位符的替換由BeanFactoryPostProcessor完成。 這曾經是PropertyPlaceholderConfigurer ，但是從Spring 3.1開始就有PropertySourcesPlaceholderConfigurer 。 我認為這是向上下文添加這種類型的bean的問題。 它的文檔表明它針對Environment解析了占位符：

* Specialization of {@link org.springframework.beans.factory.config.PlaceholderConfigurerSupport
 * PlaceholderConfigurerSupport} that resolves ${...} placeholders within bean definition
 * property values and {@code @Value} annotations against the current Spring {@link
 * Environment} and its set of {@link PropertySources}.

Answer 2

設法解決解決方案。 我將PropertySoure （ s ）移到了RootConfig ，該RootConfig公開了PropertySourcesPlaceholderConfigurer bean。

@PropertySources({
    @PropertySource(ignoreResourceNotFound = true,
                    value = "classpath:app.config.properties"),
    @PropertySource(ignoreResourceNotFound = true,
                    value = "classpath:app.user.config.properties"),
    @PropertySource(ignoreResourceNotFound = true,
                    value = "file:///${app.config}")
})
public class RootConfig {

    @Bean
    public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
        return new PropertySourcesPlaceholderConfigurer();
    }

}