Question

How can I use sling object in a java class(Servlet), I can use that in a jsp file. Can we use that in a java file.
Like this in a Java class:

sling.getService(LoginServiceClient.class)

Answer 1

I belive that you’re trying to get OSGi service (LoginServiceClient) in some servlet. If your servlet is also managed by the OSGi (so it’s annoted with @Component annotation), then you can use dependency injection to get any service you want:

@Component(immediate = true)
@Service
@Properties({
    @Property(name = ServletResolverConstants.SLING_SERVLET_PATHS, value = "/my/servlet/path"),
    @Property(name = ServletResolverConstants.SLING_SERVLET_METHODS, value = { HttpConstants.METHOD_GET })
})

public class MyServlet extends SlingSafeMethodsServlet {
    @Reference
    LoginServiceClient loginServiceClient;
...
}

All these annotations are handled by the Maven SCR plugin.