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How can I inject a property value into a Spring Bean which was configured using annotations

I have a bunch of Spring beans which are picked up from the classpath via annotations, e.g.

@Repository("personDao")
public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao {
    // Implementation omitted
}


In the Spring XML file, there"s a PropertyPlaceholderConfigurer defined:

<bean id="propertyConfigurer"
  class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location" value="/WEB-INF/app.properties" />
</bean>


I want to inject one of the properties from app.properites into the bean shown above. I can"t simply do something like

<bean class="com.example.PersonDaoImpl">
    <property name="maxResults" value="${results.max}"/>
</bean>


Because PersonDaoImpl does not feature in the Spring XML file (it is picked up from the classpath via annotations). I"ve got as far as the following:

@Repository("personDao")
public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao {

    @Resource(name = "propertyConfigurer")
    protected void setProperties(PropertyPlaceholderConfigurer ppc) {
    // Now how do I access results.max?
    }
}


But it"s not clear to me how I access the property?

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You can do this in Spring 3 using EL support. Example:


@Value("#{systemProperties.databaseName}")

public void setDatabaseName(String dbName) { ... }


@Value("#{strategyBean.databaseKeyGenerator}")

public void setKeyGenerator(KeyGenerator kg) { ... }


systemProperties is an implicit object and strategyBean is a bean name.

One more example, which works when you want to grab a property from a Properties object. It also shows that you can apply @Value to fields:


@Value("#{myProperties['github.oauth.clientId']}")

private String githubOauthClientId;


Answer is