Here are some suggestions for using a design pattern on a project within the next hour:- Template Method pattern - Create an abstract class with common functionality and allow subclasses to override specific steps. For example, a report generator class.- Factory pattern - Create an object without exposing the instantiation logic. For example, a user factory that returns different user types. - Observer pattern - Define a subscription mechanism for notifying multiple objects about any events that happen to the object they're observing. For example, notifications when a user profile is updated.- Strategy pattern - Encapsulate families of algorithms and make them interchangeable. For example, different sorting or authentication strategies. - Command pattern - Encapsulate a
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Ähnlich wie Here are some suggestions for using a design pattern on a project within the next hour:- Template Method pattern - Create an abstract class with common functionality and allow subclasses to override specific steps. For example, a report generator class.- Factory pattern - Create an object without exposing the instantiation logic. For example, a user factory that returns different user types. - Observer pattern - Define a subscription mechanism for notifying multiple objects about any events that happen to the object they're observing. For example, notifications when a user profile is updated.- Strategy pattern - Encapsulate families of algorithms and make them interchangeable. For example, different sorting or authentication strategies. - Command pattern - Encapsulate a
Ähnlich wie Here are some suggestions for using a design pattern on a project within the next hour:- Template Method pattern - Create an abstract class with common functionality and allow subclasses to override specific steps. For example, a report generator class.- Factory pattern - Create an object without exposing the instantiation logic. For example, a user factory that returns different user types. - Observer pattern - Define a subscription mechanism for notifying multiple objects about any events that happen to the object they're observing. For example, notifications when a user profile is updated.- Strategy pattern - Encapsulate families of algorithms and make them interchangeable. For example, different sorting or authentication strategies. - Command pattern - Encapsulate a (20)
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Here are some suggestions for using a design pattern on a project within the next hour:- Template Method pattern - Create an abstract class with common functionality and allow subclasses to override specific steps. For example, a report generator class.- Factory pattern - Create an object without exposing the instantiation logic. For example, a user factory that returns different user types. - Observer pattern - Define a subscription mechanism for notifying multiple objects about any events that happen to the object they're observing. For example, notifications when a user profile is updated.- Strategy pattern - Encapsulate families of algorithms and make them interchangeable. For example, different sorting or authentication strategies. - Command pattern - Encapsulate a
- 2. A design pattern is a general reusable solution to a commonly occurring problem within a given context in software design.A design pattern is not a finished design that can be transformed directly into source or machine code. It is a description or template for how to solve a problem that can be used in many different situations. The Gang of Four (GoF)
- 5. class Report! def initialize! @title = 'Monthly Report'! @text = ['Things are going', 'really, really well.']! end! ! def output_report(format)! if format == :plain! puts("*** #{@title} ***")! elsif format == :html! puts('<html>')! puts(' <head>')! puts(" <title>#{@title}</title>")! puts(' </head>')! puts(' <body>')! else! raise "Unknown format: #{format}"! end! ! @text.each do |line|! if format == :plain! puts(line)! else! puts(" <p>#{line}</p>" )! end! end! ! if format == :html! puts(' </body>')! puts('</html>')! end! end! end!
- 6. class Report! def initialize! @title = 'Monthly Report'! @text = ['Things are going', 'really, really well.']! end! ! def output_report! output_start! output_head! output_body_start! @text.each do |line|! output_line(line)! end! output_body_end! output_end! end! ! def output_start! end! ! def output_head! raise 'Called abstract method: output_head'! end! ! def output_body_start! end! ! def output_line(line)! raise 'Called abstract method: output_line'! end! ! def output_body_end! end! ! def output_end! end! end! Template method
- 7. class HTMLReport < Report! def output_start! puts('<html>')! end! ! def output_head! puts(' <head>')! puts(" <title>#{@title}</title>")! puts(' </head>')! end! ! def output_body_start! puts('<body>')! end! ! def output_line(line)! puts(" <p>#{line}</p>")! end! ! def output_body_end! puts('</body>')! end! ! def output_end! puts('</html>')! end! end!
- 9. class Report! attr_reader :title, :text! attr_accessor :formatter! ! def initialize(formatter)! @title = 'Monthly Report'! @text = ['Things are going', 'really, really well.']! @formatter = formatter! end! ! def output_report! @formatter.output_report(self)! end! end! ! Report.new(HTMLFormatter.new)
- 10. class HTMLFormatter! def output_report(context)! puts('<html>')! puts(' <head>')! # Output The rest of the report ...! ! puts(" <title>#{context.title}</title>")! puts(' </head>')! puts(' <body>')! context.text.each do |line|! puts(" <p>#{line}</p>")! end! puts(' </body>')! ! puts('</html>')! end! end!
- 12. class User! def save! save_to_database! if new_record?! notify_observers(:after_create)! end! notify_observers(:after_save)! end! end! ! class UserEmailObserver! def after_create(user)! UserMailer.welcome_email(user)! end! end! ! user = User.new! user.add_observer(UserEmailObserver.new)!
- 14. class Task! attr_reader :name! ! def initialize(name)! @name = name! end! ! def get_time_required! 0.0! end! end
- 15. class CompositeTask < Task ! def initialize(name)! super(name)! @sub_tasks = []! end! ! def add_sub_task(task)! @sub_tasks << task! end! ! def remove_sub_task(task)! @sub_tasks.delete(task)! end! ! def get_time_required! time=0.0! @sub_tasks.each {|task| time += task.get_time_required}! time! end! end!
- 16. class MakeCakeTask < CompositeTask! def initialize! super('Make cake')! add_sub_task( MakeBatterTask.new )! add_sub_task( FillPanTask.new )! add_sub_task( BakeTask.new )! add_sub_task( FrostTask.new )! add_sub_task( LickSpoonTask.new )! end! end! ! MakeCakeTask.new.get_time_required
- 18. External array = ['red', 'green', 'blue']! ! i = ArrayIterator.new(array)! while i.has_next?! puts "item: #{i.next_item}"! end! Hello Java ;-)
- 19. Internal array = ['red', 'green', 'blue']! array.each do |item|! puts "item: #{item}"! end!
- 20. External array1 = [1, 2]! array1 = [2, 3]! ! sum = 0! i1 = ArrayIterator.new(array1)! i2 = ArrayIterator.new(array2)! while i1.has_next? && i2.has_next?! sum += i1.next_item * i2.next_item! end!
- 22. PrimerTemplate Method class SlickButton! def on_button_push! raise "Abstract method on_button_push"! end! end! ! class SaveButton < SlickButton! def on_button_push! document.save(filename)! end! end So many subclasses :-(
- 23. class SlickButton! attr_accessor :command! ! def initialize(command)! @command = command! end! ! def on_button_push! @command.execute if @command! end! end! ! class SaveCommand! def execute! # Save the current document...! end! end! Command Pattern
- 24. class SlickButton! attr_accessor :command! ! def initialize(&block)! @command = block! end! ! def on_button_push! @command.call if @command! end! end! ! save_button = SlickButton.new do! document.save(filename)! end! Lambda
- 25. Composite, Command PRIMER - INSTALLER
- 26. class Command! attr_reader :description! ! def initialize(description)! @description = description! end! ! def execute! end! ! def unexecute! end! end! ! class CreateFile < Command! def initialize(path, contents)! super "Create file: #{path}"! @path = path! @contents = contents! end! ! def execute! f = File.open(@path, "w")! f.write(@contents)! f.close! end! ! def unexecute! File.delete(@path)! end! end!
- 27. class CompositeCommand < Command! def initialize! @commands = []! end! ! def add_command(cmd)! @commands << cmd! end! ! def execute! @commands.each { |cmd| cmd.execute }! end! ! # ...! ! def unexecute! @commands.reverse.each { |cmd| cmd.unexecute }! end! ! # ...! ! def description! description = ''! @commands.each { |cmd| description += cmd.description + "n" }! return description! end! end!
- 28. class Installer < CompositeCommand! def initialize! add_command(CreateFile.new("file1.txt", "hello worldn"))! add_command(CopyFile.new("file1.txt", "file2.txt"))! add_command(DeleteFile.new("file1.txt"))! end! end! ! installer = Installer.new! installer.execute! puts installer.description!
- 30. class Database! def initialize(adapter)! @adapter = adapter! end! ! def create_table(table_name, fields)! @adapter.create_table(table_name)! fields.each_pair do |name, type|! @adapter.create_column(table_name, name, type)! end! end! end! ! db = Database.new(MySQLAdapter.new(DB_URI))! db.create_table(:users, email: :string)!
- 32. class AccountProtectionProxy! def initialize(real_account, owner_name)! @subject = real_account! @owner_name = owner_name! end! ! def withdraw(amount)! check_access! return @subject.withdraw(amount)! end! ! def check_access! if Etc.getlogin != @owner_name ! raise "Illegal access: #{Etc.getlogin} cannot access account."! end! end! end!
- 34. class UserDecorator! attr_reader :user! delegate :first_name, :last_name,! :position, :institution, to: :user! ! def initialize(user)! @user = user! end! ! def short_name! "#{first_name[0]}. #{last_name}"! end! ! def description! "#{short_name} is a #{position} at #{institution}"! end! end! <p>! <b>Name:<b>! {{short_name}}! <br>! {{description}}! <p>!
- 36. class SimpleLogger! @@instance = SimpleLogger.new! ! def self.instance! return @@instance! end! ! def warn(s)! puts s! end! end! ! SimpleLogger.instance.warn("I don't know what I'm doing")!
- 38. factory :user do! first_name 'John'! last_name 'Doe'! admin false! ! factory :admin do! admin true! end! end! ! FactoryGirl.build(:user)! FactoryGirl.build(:admin)!
- 40. user = UserBuilder.new('John', 'Doe')! .age(30)! .phone('1234567')! .address('Fake address 1234')! .build()! Hello Java ;-)
- 42. AST (Abstract SyntaxTree) querying stuff, building SQL, etc. # Files that are bigger than 20KB and not writable,! # or are mp3 files! expr = Or.new(! And.new(Bigger.new(20.kilobytes), Not.new(Writable.new)),! FileName.new('*.mp3'))! expr.evaluate # => [File, File, ...]!
- 43. •teamleadi določite enega ki naj v naslednji 1 uri uporabi na projektu enega od patternov •checkmarks