Talk:Builder pattern: Difference between revisions

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==Why builders?==

Builders are an OOP pattern to construct complex objects without overloading a constructor. The important part is that you don’t need to call all of the steps to construct. You can call only those steps that are necessary for producing a particular configuration of an object. Also a `director` class helps the builder to construct a specific type of object. I'm missing these concepts in the article. [[User:Theking2|Theking2]] ([[User talk:Theking2|talk]]) 20:52, 25 November 2024 (UTC)

:This is helpful. I've read the wiki and it's still isn't entirely clear to me how or why I would use this. [[User:Jgoure|Jgoure]] ([[User talk:Jgoure|talk]]) 21:49, 7 April 2025 (UTC)

==Builders and immutable objects==

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A major benefit of builders is that they can be used to create immutable objects without complex constructors. In Java, the builder pattern also simulates named constructor parameters:

<sourcesyntaxhighlight lang="java">

public final class Pizza {

private final String dough;

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}

}

</syntaxhighlight>

</source>

==Abstract Builder class==

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This seems to say that the Builder manages "the correct sequence of object creation". Is the client the "Director" or is the builder the "Director"? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/61.14.96.7|61.14.96.7]] ([[User talk:61.14.96.7|talk]]) 07:51, 30 April 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->

:According to the UML, the client is the Director. And I believe the word "Director" should be replaced with "Client" for clarity and to avoid confusion since some people tend to think "Director" is a class which is part of the pattern. [[Special:Contributions/186.0.181.64|186.0.181.64]] ([[User talk:186.0.181.64|talk]]) 17:46, 10 April 2023 (UTC)

== Missing the Mark ==

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== Two example implementations ==

I'm not sure we need two example implementations. C++ and Java are not radically different in syntax, and there's nothing about the pattern that can't be covered in one. &mdash;&nbsp;[[User:Anndelion|<fontspan colorstyle="color:#6B8E23;">'''anndelion'''</fontspan>]]&nbsp;[[User_talk:Anndelion|<span style="font-size:125%; vertical-align:text-middle; color:#DAA520"><span class="Unicode">&#10059;</span></span>]] 21:40, 18 April 2011 (UTC)

:Not terribly impressed by the C++ example either - don't expose pointers, use references instead, and the Builder certainly cannot be a singleton. As an example, use more meaningful names - ideally (necessarily) the same as those in other examples to emphasis the relationship between the representations in different languages. [[Special:Contributions/15.203.137.74|15.203.137.74]] ([[User talk:15.203.137.74|talk]]) 12:19, 26 November 2014 (UTC)

== C# implementation ==

In keeping with C# style, shouldn't properties be used instead of java-like setters?

<sourcesyntaxhighlight lang = "csharp">

public string Dough {

get {return _dough;}

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}

...

</syntaxhighlight>

</source>

== Critics ==

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disappears:

<sourcesyntaxhighlight lang="python">

class Pizza:

def __init__(self,dough='Hand Tossed', sauce='Marinara', topping='Cheese'):

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# Use the standard dough

p = Pizza(sauce='Garlic Butter', topping='Pepperoni')

</syntaxhighlight>

</source>

...But then, the "Definition" section of the article says this:

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A less abstract example might be DocumentBuilder with addParagraph, addImage etc methods. Then we could have a PdfDocumentBuilder, WordDocumentBuilder etc implementations. [[Special:Contributions/81.187.215.34|81.187.215.34]] ([[User talk:81.187.215.34|talk]]) 11:23, 10 July 2016 (UTC)

:The current example is no longer about cars. [[User:Dandv|<span style="text-shadow:lightgrey 0.3em 0.3em 0.15em;">Dandv</span>]] 04:33, 6 October 2022 (UTC)

== UML class and sequence diagram ==

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[[User:Mlouns|Mlouns]] ([[User talk:Mlouns|talk]]) 22:43, 3 June 2019 (UTC)

:This was resolved. Can we delete the section? [[User:Dandv|<span style="text-shadow:lightgrey 0.3em 0.3em 0.15em;">Dandv</span>]] 04:32, 6 October 2022 (UTC)

== Confusing Bicycle example ==

I find the Pizza example given on this Talk page in 2007 ([[#Builders_and_immutable_objects]]) far easier to follow than the [https://en.wikipedia.org/w/index.php?title=Builder_pattern&oldid=1102311912#Examples current Bicycle example]. -- [[User:Dandv|<span style="text-shadow:lightgrey 0.3em 0.3em 0.15em;">Dandv</span>]] 04:30, 6 October 2022 (UTC)