How to Inject a Property Value into a Spring Bean Which Was Configured Using Annotations

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

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;

Here is a blog post I wrote about this for a little more info.

Spring: How to inject a property value into the bean via XML?

Try this:

<bean id="myBean" class="com.test.MyBean">
    <property name="value" value="${app.settings.value}"/>
</bean>

The syntax is the same as for java config - prefixed with the $ sign.

Inject property to spring bean using annotation

Ok, got it!

I'm using a spring MVC project, which means I have a separated context for my web layer (the controllers). The "Configuration" bean which hods the properties using the @Value annotation is injected to a controller. My property-placeholder is defined within my root-context hence it cannot be seen from my controller. To resolve the issue I simply added the property-placeholder definition to my DispatcherServlet context and it works like a charm :)

property value injection into spring beans

Basically propertyValue is null because Spring injects value after bean's creation.
So when you do:

@Bean
public IWebserviceEndpoint webserviceEndpoint() {
  return new WebserviceEndpoint();
}

Spring creates a new instance with propertyValue=null.
You can initialize your instance attribue with @ConfigurationProperties

@Bean
@ConfigurationProperties(prefix=...)
public IWebserviceEndpoint webserviceEndpoint() {
   return new WebserviceEndpoint();
}

Note that propertyValue should have a setter.

You have several ways to solve this problem, usually it's good to centralize properties in one utils class.

@Component
public class Configs {
  @Value("${propery}"
  String property;

  String getProperty(){ 
    return property;
  }
}

And then:

@Bean
@ConfigurationProperties(prefix=...)
public IWebserviceEndpoint webserviceEndpoint() {
    WebserviceEndpoint we = new WebserviceEndpoint();
    we.setProperty(configs.getProperty())
   return we;
}

Again there are many many different ways to solve this problem

Injecting Properties using Spring & annotation @Value

For your solution to work you would also need to make foo a Spring managed bean; because otherwise how would Spring know that it has to deal with any of your annotations on your class?

• You can either specify it in your appcontext xml as a bean with ..class="foo"
• Or use component-scan and specify a base package which contains your foo class.

Since I'm not entirely sure this is exactly what you want (don't you want a .properties file to be parsed by Spring and have it's key-value pairs available instead of a Properties object?), I'm suggesting you another solution: Using the util namespace

<util:properties id="props" location="classpath:com/foo/bar/props.properties"/>

And reference the values inside your beans (also, have to be Spring managed):

@Value("#{props.foo}")
public void setFoo(String foo) {
    this.foo = foo;
}

EDIT:

just realized that you are importing org.springframework.context.ApplicationContext in your class which is probably unnecessary. I strongly encourage you to read Spring reference at least the first few chapters, because a) it's a great read b) you will find it much easier to understand Spring if the basics are clear.

Spring inject property values from a bean into another bean

Try using the expression langugage:

@Value(#{anotherBean.location})
private String location
@Value(#{anotherBean.enabled})
private boolean enabled

Update

Alternatively you can assign that in the post construct:

@Autowired
private AnotherBean anotherBean;

@PostConstruct
public void init(){
    location = anotherBean.getLocation();
    enabled = anotherBean.isEnabled();
}

Update 2

The last thing that comes to my mind that could work out of the box is changing the scope of the first bean to prototype instead of singleton:

@Scope("prototype")

Now everytime this bean would used (getBean on spring context for example) a new instance would be created.. and everytime fresh data from anotherBean wouuld be injected.

But this is specific so you would have to think whether this scenario fits your application.

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