Question

I’ve a class as shown below:

@Path("/myrequest")
@Scope("request")
@Component
public class MyRESTCode implements IServicedResource<T> {   
@Inject
private IMyService serviceImpl;

@Override
public void setServiceImpl(IMyService impl) {
    serviceImpl = impl;
}
}

@Path("/users")
@POST
@Consumes ({MediaType.APPLICATION_JSON})
@Produces ({MediaType.APPLICATION_JSON})
public Response mymethod(Object obj) throws Exception {
       serviceImpl.callme(obj);
       return Response.noContent().build();
}

Now, this callme method implementation exists in some other class (MyOtherClass.java).

Can any one tell me how mymethod invokes callme method in MyOtherClass.java, when /users POST request is made???

Also, who calls setServiceImpl method & how does it get set & when does it get called?

Thanks!

Answer 1

You must be having a spring applicationContext.xml which should look something like

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns: xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
            http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
            http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd">

       <context:component-scan base-package="test.example"/>
       <context:annotation-config/>

</beans>

In this xml, if you notice that base-package should be defined as a package where your controller class (in your case MyRESTCode.java) should be present. Spring will search for classes annotated as @Component and configures them at the path mentioned by @Path

When you hit the a post request with JSON in the body to the URL …./myrequest/users, the callme method gets invoked which in turn invokes your service method.

@Inject annotation tells spring that dependency of IMyService should be injected to serviceImpl variable through the setter method setServiceImpl.

Hope this helps.