Framework-Driven Application Development & RESTful Services

Question 1

What is a software library?

Answer 1

A reusable archive of shared code (classes, interfaces, exceptions, annotations) that application code calls when needed

Question 2

What is a software framework?

Answer 2

A predefined flow of logic with “gaps” for app code. The framework controls execution and calls your code (inversion of control)

Question 3

What principle differentiates frameworks from libraries?

Answer 3

Inversion of control: the framework manages execution flow, and developers “plug in” code

Question 4

What is dependency injection?

Answer 4

Technique to achieve inversion of control by injecting dependencies rather than hardcoding them

Question 5

What is the Spring framework?

Answer 5

An application development framework relying on inversion of control via dependency injection

Question 6

What is a Spring “Bean”?

Answer 6

A class managed by the Spring IoC container, with dependencies configured via metadata

Question 7

What is Spring Boot?

Answer 7

A Spring-based framework that simplifies setup by providing conventional defaults, eliminating most XML configuration

Question 8

What is HTTP?

Answer 8

Hypertext Transfer Protocol — stateless, request/response-based, application-layer protocol

Question 9

What are the main HTTP verbs?

Answer 9

GET (fetch), POST (create), PUT (create/update), DELETE (delete)

Question 10

Example URL breakdown:
https://vsb.mcgill.ca:8080/vsb/criteria.jsp?term=202509&courses=ECSE-321

Answer 10

Protocol: https

Host: vsb.mcgill.ca

Port: 8080

Path: /vsb/criteria.jsp

Query: term=202509&courses=ECSE-321

Question 11

HTTP Status Code categories?

Answer 11

1xx Informational

2xx Success (200 OK, 202 Accepted, 204 No Content)

3xx Redirection (301 Moved, 304 Not Modified)

4xx Client errors (400 Bad Request, 401 Unauthorized, 403 Forbidden, 404 Not Found, 409 Conflict)

5xx Server errors (500 Internal Error, 503 Service Unavailable)

Question 12

What does REST stand for?

Answer 12

Representational State Transfer

Question 13

What are the characteristics of RESTful services?

Answer 13

Resource-centered

Operate via URIs

Use standard HTTP verbs

Pass data as JSON/XML

Question 14

What does “idempotent” mean in HTTP methods?

Answer 14

Repeating a request has the same effect as a single request (e.g., PUT is idempotent, POST is not)

Question 15

Why is JSON commonly used in REST?

Answer 15

Lightweight, text-only, human-readable, and easily maps to objects

Question 16

How should REST integrate with MVC?

Answer 16

REST aligns best with the Controller (not exposing Model directly), to protect server control and prevent illegal state manipulation

Question 17

Why not expose Model directly in REST?

Answer 17

Risks include information leaks, unauthorized state changes, and loss of server-side control