Question

I needed to initialize a bean at the application startup so I did that in applicationContext.xml. But now I need to inject that bean into an object which is created at runtime. Example:

Servlet

...
void doPost(...) {
    new Handler(request); 
}
...

Handler

public class Handler {

    ProfileManager pm; // I need to inject this ???

    Handler(Request request) {
        handleRequest(request);
    }

    void handleRequest(Request request) {
        pm.getProfile(); // example
    }
}

Answer 1

Better approach would be to declare the Handler as Bean as well – assuming that the ProfileManager is already declared – and then autowire the ProfileManager in the Handler bean either with the annotation @Autowired if you are using annotations in your apps, or inside the applicationContext.xml.
An example of how to do it in the xml could be:

<bean id="profileManager" class="pckg.ProfileManager" />
<bean id="handler" class="pckg.Handler" >
 <property name="pm" ref="profileManager" />
</bean>

If you do NOT want to register Handler as bean instantiate it as you do and take the pm instance from spring’s ApplicationContext. A way of how to get ApplicationContext inside a web app is shown here