Sling & OSGi - Fundamentals Quiz 1

Question 1

Configuration Admin

What manages persistent OSGi component configuration values?

Context: Configuration

JCR Session Configuration Admin Dispatcher Sling Engine

Question 2

Service injection

Which annotation is used to inject an OSGi service into a DS component?

Context: DS

@Activate @Modified @Designate @Reference

Question 3

Selecting among multiple OSGi services

Several OSGi services implement the same interface and a consumer has a single mandatory reference to that interface. Which service is chosen by default?

Context: Service resolution

The oldest registered service The service with the lowest PID The service with the highest service.ranking All matching services simultaneously

Question 4

Optional service reference

How can a DS reference permit component activation when no service is available?

Context: DS

Set immediate to true Use @Deactivate Set service ranking to zero Set cardinality to OPTIONAL

Question 5

Import Package

What does an OSGi bundle Import-Package header declare?

Context: Bundles

Java packages required from other bundles Servlet URL patterns OSGi configuration values Repository paths to install

Question 6

Declarative Services component

Which annotation marks a class as an OSGi Declarative Services component?

Context: DS

@Inject @Component @Path @Model

Question 7

Why use a factory configuration

What is the main effect of creating multiple configurations for a factory PID?

Context: Configuration patterns

One configuration is merged into a global singleton The component stops being an OSGi service It forces the service to run only on publish Multiple component instances are created from the same implementation

Question 8

How EventHandler delivery works

If three EventHandler services subscribe to the same event topic, what normally happens when that event is sent?

Context: Event processing

Only the highest-ranked handler receives it The event is dropped unless one handler returns true All matching handlers receive the event Only handlers on author receive it

Question 9

Configuration modification

What is @Modified used for in a DS component?

Context: DS

Question 10

Service interface registration

What does service=MyService.class in @Component specify?

Context: DS

The service interface exposed by the component The JCR node type The servlet resource type The component configuration PID

Question 11

Service ranking

What does a higher OSGi service.ranking generally affect?

Context: OSGi services

Repository permission inheritance Bundle installation order Preference when selecting among matching services HTTP response status

Question 12

What usually triggers an OSGi component to become active?

For a DS component in AEM, what must typically be true before the component activates?

Context: OSGi Declarative Services

The author instance is paused A workflow model is published Required references and configuration constraints are satisfied Dispatcher cache is warmed

Question 13

Why resourceType servlets are preferred

Why is registering a Sling servlet by resourceType usually preferred over registering it only by path?

Context: Servlet design

It guarantees higher performance than any path servlet It automatically bypasses CSRF protection It participates in Sling resource resolution and aligns better with content and permissions It is the only way to support POST

Question 14

Scheduler whiteboard

How can a DS component register work with the Sling Scheduler whiteboard?

Context: Scheduling

Provide scheduler properties on @Component Add a JCR mixin Use an HTL template Create a dispatcher rule

Question 15

Why should a service-acquired ResourceResolver usually be closed?

A ResourceResolver is acquired from a ResourceResolverFactory in custom code. Why should it typically be closed in a finally block or try-with-resources pattern?

Context: AEM service code

It republishes modified content automatically It upgrades Oak indexes It releases underlying resources and avoids session or resolver leaks Closing it clears dispatcher cache

Question 16

Activation method

When is a method annotated with @Activate called?

Context: DS

When a servlet receives GET When a package is built When a page is published When the component becomes active

Question 17

Active bundle state

What does an Active OSGi bundle state mean?

Context: Bundles

The bundle has been uninstalled The bundle is only installed The bundle has started successfully The bundle is permanently disabled

Question 18

Metatype annotations

What does an @ObjectClassDefinition interface describe?

Context: Configuration

Configuration metadata A JCR node schema A client library An HTTP endpoint

Question 19

Immediate components

What does immediate=true on a DS component request?

Context: DS

Disable configuration Run on every request Activate without waiting for service consumption Ignore missing references

Question 20

Designate annotation

What does @Designate connect to a DS component?

Context: Configuration

An ObjectClassDefinition configuration A replication queue A servlet selector A repository path

AEM CQ5 Tutorials

Sling & OSGi – Fundamentals Quiz 1

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

Question 13

Question 14

Question 15

Question 16

Question 17

Question 18

Question 19

Question 20

Related