Programmatic access to properties created by property-placeholder

Question

I\'m reading properties file using context:property-placeholder. How can I access them programatically (@Value doesn\'t work - I d

Answer 1

Create beans for your properties before putting them in property-placeholder to make the properties easy to access in-code.

Ex:

<bean id="configProperties" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
    <property name="resources" value="classpath:META-INF/spring/config.properties" />
</bean>

<context:property-placeholder properties-ref="configProperties" ignore-unresolvable="true"/>

Code:

@Autowired
private PropertiesFactoryBean configProperties;

You can also use @Resource(name="configProperties")

Answer 2

We use the following approach to access properties for our applications

<util:properties id="appProperties" location="classpath:app-config.properties" />
<context:property-placeholder properties-ref="appProperties"/>

Then you have the luxury of just autowiring properties into beans using a qualifier.

@Component
public class PropertyAccessBean {

    private Properties properties;

    @Autowired
    @Qualifier("appProperties")
    public void setProperties(Properties properties) {
        this.properties = properties;
    }

    public void doSomething() {
        String property = properties.getProperty("code.version");
    }

}

If you have more complex properties you can still use ignore-resource-not-found and ignore-unresolvable. We use this approach to externalise some of our application settings.

 <util:properties id="appProperties" ignore-resource-not-found="true"
    location="classpath:build.properties,classpath:application.properties,
                            file:/data/override.properties"/>
 <context:property-placeholder ignore-unresolvable="true" properties-ref="appProperties"/>

Answer 3

No you can't. PropertyPlaceholderConfigurer is a BeanFactoryPostProcessor, it is only "alive" during bean creation. When it encounters a ${property} notation, it tries to resolve that against its internal properties, but it does not make these properties available to the container.

That said: similar questions have appeared again and again, the proposed solution is usually to subclass PropertyPlaceHolderConfigurer and make the Properties available to the context manually. Or use a PropertiesFactoryBean