Beyond @Value: Two painless ways to inject properties early in Spring Boot

In Spring, @Value, Environment, and @ConfigurationProperties inject configuration properties via a BeanPostProcessor, which runs after BeanFactoryPostProcessor processing. Therefore these annotations cannot be used inside a BeanFactoryPostProcessor.

Injecting properties with Environment

Use the Environment abstraction to read properties early in the container lifecycle.

Method 1 – Direct Environment#getProperty

@Bean
public static BeanFactoryPostProcessor beanFactoryPostProcessor(Environment environment) {
    return beanFactory -> {
        String title = environment.getProperty("pack.app.title", String.class);
        BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
        registry.registerBeanDefinition("packTitle",
            BeanDefinitionBuilder.genericBeanDefinition(String.class)
                .addConstructorArgValue(title)
                .getBeanDefinition());
    };
}

This approach reads a single property value directly. It is simple but becomes verbose when many properties are required.

Method 2 – Binder with @ConfigurationProperties

@Bean
public BeanFactoryPostProcessor packBeanFactoryPostProcessor(Environment environment) {
    return beanFactory -> {
        BindResult<AKFProperties> result = Binder.get(environment)
            .bind("pack.app", AKFProperties.class);
        AKFProperties properties = result.get();
        BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
        registry.registerBeanDefinition("packTitle",
            BeanDefinitionBuilder.genericBeanDefinition(App.class)
                .addConstructorArgValue(properties.getTitle())
                .addConstructorArgValue(properties.getVersion())
                .getBeanDefinition());
    };
}

@ConfigurationProperties(prefix = "pack.app")
public static class AKFProperties {
    private String title;
    private String version;
    // getters and setters
}

The Binder loads the entire property group into a POJO, making management of multiple settings easier.

Component‑based registration

Declare a class that implements BeanFactoryPostProcessor and EnvironmentAware so the Environment can be injected.

@Component
public class PackAppBeanFactoryPostProcessor implements BeanFactoryPostProcessor, EnvironmentAware {
    private Environment environment;

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        String title = environment.getProperty("pack.app.title", String.class);
        BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
        registry.registerBeanDefinition("packTitle",
            BeanDefinitionBuilder.genericBeanDefinition(App.class)
                .addConstructorArgValue(title)
                .getBeanDefinition());
    }

    @Override
    public void setEnvironment(Environment environment) {
        this.environment = environment;
    }
}

Constructor injection or @Resource cannot be used for Environment in a BeanFactoryPostProcessor because the bean instance is created before those mechanisms are active.

Key warnings

Do not use @Value inside a BeanFactoryPostProcessor – the corresponding BeanPostProcessor has not run yet.

Avoid @Resource or constructor injection for Environment in this context.

These approaches enable early‑stage property injection for Spring Boot 3.5.0 applications.