Design Patterns and Principles

Question 1

“Design is not just how it
looks and feels like.
Design is how it works”

Answer 1

What is Design?
● According to Steve Jobs , Cofounder
of Apple:

Question 2

• is the creation of an experience.
• It’s also the process of the said creation and how well it’s
  organized.
• On top of that, design is the result , i.e. the things we see,
  hear, and feel.
• is a plan for arranging elements in such a way as
  best to accomplish a particular purpose

Answer 2

Design

Question 3

• are typical solutions to
  commonly occurring problems in software
  design.
• They are like pre made blue prints that you
  can customize to solve a recurring design
  problem in your code.

Answer 3

Design patterns

Question 4

The pattern is not a specific piece of code,
but a __ __ for solving a
particular problem.

Answer 4

general concept

Question 5

Design patterns are often confused with
algorithms because they both describe
typical solutions (True or false)

Answer 5

True

Question 6

While an algorithm always defines a clear
set of actions that can achieve some goal, a
pattern is a more ____ of a
solution.

Answer 6

high level description

Question 7

● Algorithm is a __ , where each
step is required to achieve a goal.
● Design pattern is a ___ , where the
results are visible, but the implementation is
up to you.

Answer 7

cooking recipe, blueprint

Question 8

sections that are usually present in a
pattern description:

Answer 8

Intent
Motivation
Structure
Code Example

Question 9

briefly describes both the problem and
the solution.

Answer 9

Intent

Question 10

shows each part of the pattern and how
they are related.

Answer 10

Structure

Question 11

Some pattern catalogs list other useful
details, such as:

Answer 11

applicability of the
pattern, implementation steps and
relations with other patterns

Question 11

further explains the problem and the solution the
pattern makes possible.

Answer 11

Motivation

Question 12

one of the popular programming languages
makes it easier to grasp the idea behind the pattern.

Answer 12

Code example

Question 13

The most basic and low level patterns are
often called ___ . They usually apply only to
a single programming language.

Answer 13

idioms

Question 14

The most universal and high level patterns are_____. Developers can
implement these patterns in virtual ly any
language.

Answer 14

architectural patterns

Question 15

Pattern Description 3 main groups

Answer 15

Creational patterns
Structural patterns
Behavioral patterns

Question 16

provide object creation mechanisms that
increase flexibility and reuse of existing code.

Answer 16

Creational patterns provide

Question 17

explain how to assemble objects and class es into
larger structures, while keeping the structures flexible and efficient.

Answer 17

Structural patterns

Question 18

take care of effective communication and the
assignment of responsibilities between objects.

Answer 18

Behavioral patterns

Question 19

are typical solutions to common problems in object
oriented design.

Answer 19

Patterns

Question 20

The concept of patterns was first described by __ in A Pattern Language:
Towns, Buildings, Construction

Answer 20

Christopher Alexander

Question 21

The book describes a “ for designing
the urban environment . The units of this
language are patterns.

Answer 21

A Pattern Language:
Towns, Buildings, Construction

Question 22

The idea was picked up by four authors:

Answer 22

Erich
Gamma, John Vlissides Ralph Johnson, and
Richard Helm

Question 23

In 1995, they pub lished Design Patterns: Elements of Reusable Object Oriented Software in which they applied the concept of design patterns to programming.

Answer 23

Erich
Gamma, John Vlissides Ralph Johnson, and
Richard Helm

Question 24

The book featured 23 patterns solving various
problems of object oriented design and became
a best seller very quickly.

Answer 24

Design Patterns: Elements
of Reusable Object Oriented Software

Question 25

Due to its lengthy name, people started to call it
“the book by the gang of four” which was soon shortened to simply “___”

Answer 25

the GOF book

Question 26

Since then, dozens of other object
oriented patterns have been
discovered. The “___”
became very popular in other
programming fields, so lots of other
patterns now exist outside of object
oriented design as well.

Answer 26

pattern approach

Question 27

are a toolkit of tried and tested solutions to
common problems in software design.

Answer 27

Design patterns

Question 28

define a common language that you and your
teammates can use to communicate more efficiently.

Answer 28

Design patterns