Spring @Configuration file with PropertyPlaceholderConfigurer bean doesn't resolve @Value annotation

Question

I have following configuration file:

@Configuration
public class PropertyPlaceholderConfigurerConfig {

    @Value(\"${property:defaultValue}\")
    private          


        

Answer 1

From Spring JavaDoc:

In order to resolve ${...} placeholders in definitions or @Value annotations using properties from a PropertySource, one must register a PropertySourcesPlaceholderConfigurer. This happens automatically when using in XML, but must be explicitly registered using a static @Bean method when using @Configuration classes. See the "Working with externalized values" section of @Configuration's javadoc and "a note on BeanFactoryPostProcessor-returning @Bean methods" of @Bean's javadoc for details and examples.

So, you are trying to use a placeholder in the code block required to enable placeholder processing.

As @M.Deinum mentioned, you should use a PropertySource (default or custom implementation).

Example below shows how to use properties in a PropertySource annotation as well as how to inject properties from the PropertySource in a field.

@Configuration
@PropertySource(
          value={"classpath:properties/${property:defaultValue}.properties"},
          ignoreResourceNotFound = true)
public class ConfigExample {

    @Value("${propertyNameFromFile:defaultValue}")
    String propertyToBeInjected;

    /**
     * Property placeholder configurer needed to process @Value annotations
     */
     @Bean
     public static PropertySourcesPlaceholderConfigurer propertyConfigurer() {
        return new PropertySourcesPlaceholderConfigurer();
     }
}