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<title>Template method pattern</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Template method pattern</span></span>

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</style><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="Template_processor" title="Template processor">Template processor</a>.</div>

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<p>In <a href="Object-oriented_programming" title="Object-oriented programming">object-oriented programming</a>, the <b>template method</b> is one of the <a href="Behavioral_pattern" title="Behavioral pattern">behavioral</a> <a href="Software_design_pattern" title="Software design pattern">design patterns</a> identified by Gamma et al.<sup id="cite_ref-:0_1-0" class="reference"><a href="#cite_note-:0-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> in the book <i><a href="Design_Patterns" title="Design Patterns">Design Patterns</a></i>. The template method is a method in a superclass, usually an abstract superclass, and defines the skeleton of an operation in terms of a number of high-level steps. These steps are themselves implemented by additional <i>helper methods</i> in the same class as the <i>template method</i>.

</p><p>The <i>helper methods</i> may be either <i><a href="Abstract_method" class="mw-redirect" title="Abstract method">abstract methods</a></i>, in which case subclasses are required to provide concrete implementations, or <i><a href="Hooking" title="Hooking">hook methods</a>,</i> which have empty bodies in the superclass. <a href="Subclass_(computer_science)" class="mw-redirect" title="Subclass (computer science)">Subclasses</a> can (but are not required to) customize the operation by <a href="Method_overriding" title="Method overriding">overriding</a> the hook methods. The intent of the template method is to define the overall structure of the operation, while allowing subclasses to refine, or redefine, certain steps.<sup id="cite_ref-:2_2-0" class="reference"><a href="#cite_note-:2-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2></div>

<p>This pattern has two main parts:

</p>

<ul><li>The "template method" is implemented as a method in a <a href="Base_class" class="mw-redirect" title="Base class">base class</a> (usually an <a href="Abstract_class" class="mw-redirect" title="Abstract class">abstract class</a>). This method contains code for the parts of the overall algorithm that are invariant. The template ensures that the overarching algorithm is always followed.<sup id="cite_ref-:0_1-1" class="reference"><a href="#cite_note-:0-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> In the template method, portions of the algorithm that may <i>vary</i> are implemented by sending self messages that request the execution of additional <i>helper</i> methods. In the base class, these helper methods are given a default implementation, or none at all (that is, they may be abstract methods).</li>

<li>Subclasses of the base class "fill in" the empty or "variant" parts of the "template" with specific algorithms that vary from one subclass to another.<sup id="cite_ref-:1_3-0" class="reference"><a href="#cite_note-:1-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> It is important that subclasses do <i>not</i> override the <i>template method</i> itself.</li></ul>

<p>At run-time, the algorithm represented by the template method is executed by sending the template message to an instance of one of the concrete subclasses. Through inheritance, the template method in the base class starts to execute. When the template method sends a message to self requesting one of the helper methods, the message will be received by the concrete sub-instance. If the helper method has been overridden, the overriding implementation in the sub-instance will execute; if it has not been overridden, the inherited implementation in the base class will execute. This mechanism ensures that the overall algorithm follows the same steps every time while allowing the details of some steps to depend on which instance received the original request to execute the algorithm.

</p><p>This pattern is an example of <a href="Inversion_of_control" title="Inversion of control">inversion of control</a> because the high-level code no longer determines what algorithms to run; a lower-level algorithm is instead selected at run-time.

</p><p>Some of the self-messages sent by the template method may be to <i><a href="Hooking" title="Hooking">hook</a> methods.</i> These methods are implemented in the same base class as the template method, but with empty bodies (i.e., they do nothing). Hook methods exist so that subclasses can override them, and can thus fine-tune the action of the algorithm <i>without</i> the need to override the template method itself. In other words, they provide a "hook" on which to "hang" variant implementations.

</p>

<div class="mw-heading mw-heading2"><h2 id="Structure">Structure</h2></div>

<div class="mw-heading mw-heading3"><h3 id="UML_class_diagram">UML class diagram</h3></div>

<p>In the above <a href="Unified_Modeling_Language" title="Unified Modeling Language">UML</a> <a href="Class_diagram" title="Class diagram">class diagram</a>, the <code>AbstractClass</code> defines a <code>templateMethod()</code> operation that defines the skeleton (template) of a behavior by

</p>

<ul><li>implementing the invariant parts of the behavior and</li>

<li>sending to <b>self</b> the messages <code>primitive1()</code> and <code>primitive2()</code> , which, because they are implemented in <code>SubClass1</code> , allow that subclass to provide a variant implementation of those parts of the algorithm.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Usage">Usage</h2></div>

<p>The <i>template method</i> is used in frameworks, where each implements the invariant parts of a domain's architecture, while providing hook methods for customization. This is an example of <a href="Inversion_of_control" title="Inversion of control">inversion of control</a>. The template method is used for the following reasons.<sup id="cite_ref-:1_3-1" class="reference"><a href="#cite_note-:1-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</p>

<ul><li>It lets subclasses implement varying behavior (through <a href="Method_overriding_(programming)" class="mw-redirect" title="Method overriding (programming)">overriding</a> of the hook methods).<sup id="cite_ref-:3_6-0" class="reference"><a href="#cite_note-:3-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></li>

<li>It avoids duplication in the code: the general workflow of the algorithm is implemented once in the abstract class's template method, and necessary variations are implemented in the subclasses.<sup id="cite_ref-:3_6-1" class="reference"><a href="#cite_note-:3-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></li>

<li>It controls the point(s) at which specialization is permitted. If the subclasses were to simply override the template method, they could make radical and arbitrary changes to the workflow. In contrast, by overriding only the hook methods, only certain specific details of the workflow can be changed,<sup id="cite_ref-:3_6-2" class="reference"><a href="#cite_note-:3-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> and the overall workflow is left intact.</li></ul>

<div class="mw-heading mw-heading3"><h3 id="Use_with_code_generators">Use with code generators</h3></div>

<p>The template pattern is useful when working with auto-generated code. The challenge of working with generated code is that changes to the source code will lead to changes in the generated code; if hand-written modifications have been made to the generated code, these will be lost. How, then, should the generated code be customized?

</p><p>The Template pattern provides a solution. If the generated code follows the template method pattern, the generated code will all be an abstract superclass. Provided that hand-written customizations are confined to a subclass, the code generator can be run again without risk of over-writing these modifications. When used with code generation, this pattern is sometimes referred to as the <a href="Generation_gap_(pattern)" title="Generation gap (pattern)">generation gap pattern</a>.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="C++_example">C++ example</h2></div>

<p>This C++14 implementation is based on the pre C++98 implementation in the book.

</p><p><span class="mw-default-size" typeof="mw:File"></span>

</p>

<div class="mw-highlight mw-highlight-lang-c++ mw-content-ltr" dir="ltr"><pre><span class="cp">#include</span><span class="w"> </span><span class="cpf"><iostream></span>

<span class="cp">#include</span><span class="w"> </span><span class="cpf"><memory></span>

<span class="k">class</span><span class="w"> </span><span class="nc">View</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="c1">// AbstractClass</span>

<span class="k">public</span><span class="o">:</span>

<span class="w"> </span><span class="c1">// defines abstract primitive operations that concrete subclasses define to implement steps of an algorithm.</span>

<span class="w"> </span><span class="k">virtual</span><span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="n">doDisplay</span><span class="p">()</span><span class="w"> </span><span class="p">{}</span>

<span class="w"> </span><span class="c1">// implements a template method defining the skeleton of an algorithm. The template method calls primitive operations as well as operations defined in AbstractClass or those of other objects.</span>

<span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="n">display</span><span class="p">()</span><span class="w"> </span><span class="p">{</span>

<span class="w"> </span><span class="n">setFocus</span><span class="p">();</span>

<span class="w"> </span><span class="n">doDisplay</span><span class="p">();</span>

<span class="w"> </span><span class="n">resetFocus</span><span class="p">();</span>

<span class="w"> </span><span class="k">virtual</span><span class="w"> </span><span class="o">~</span><span class="n">View</span><span class="p">()</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">default</span><span class="p">;</span>

<span class="k">private</span><span class="o">:</span>

<span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="n">setFocus</span><span class="p">()</span><span class="w"> </span><span class="p">{</span>

<span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">cout</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"View::setFocus</span><span class="se">\n</span><span class="s">"</span><span class="p">;</span>

<span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="n">resetFocus</span><span class="p">()</span><span class="w"> </span><span class="p">{</span>

<span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">cout</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"View::resetFocus</span><span class="se">\n</span><span class="s">"</span><span class="p">;</span>

<span class="k">class</span><span class="w"> </span><span class="nc">MyView</span><span class="w"> </span><span class="o">:</span><span class="w"> </span><span class="k">public</span><span class="w"> </span><span class="n">View</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="c1">// ConcreteClass</span>

<span class="w"> </span><span class="c1">// implements the primitive operations to carry out subclass-specific steps of the algorithm.</span>

<span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="nf">doDisplay</span><span class="p">()</span><span class="w"> </span><span class="k">override</span><span class="w"> </span><span class="p">{</span>

<span class="w"> </span><span class="c1">// render the view's contents</span>

<span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">cout</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"MyView::doDisplay</span><span class="se">\n</span><span class="s">"</span><span class="p">;</span>

<span class="w"> </span><span class="c1">// The smart pointers prevent memory leaks</span>

<span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">unique_ptr</span><span class="o"><</span><span class="n">View</span><span class="o">></span><span class="w"> </span><span class="n">myview</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">make_unique</span><span class="o"><</span><span class="n">MyView</span><span class="o">></span><span class="p">();</span>

<span class="w"> </span><span class="n">myview</span><span class="o">-></span><span class="n">display</span><span class="p">();</span>

</pre></div>

<p>The program output is

</p>

<div class="mw-highlight mw-highlight-lang-c++ mw-content-ltr" dir="ltr"><pre><span class="n">View</span><span class="o">::</span><span class="n">setFocus</span>

<span class="n">MyView</span><span class="o">::</span><span class="n">doDisplay</span>

<span class="n">View</span><span class="o">::</span><span class="n">resetFocus</span>

</pre></div>

<ul><li><a href="Inheritance_(object-oriented_programming)" title="Inheritance (object-oriented programming)">Inheritance (object-oriented programming)</a></li>

<li><a href="Method_overriding_(programming)" class="mw-redirect" title="Method overriding (programming)">Method overriding (programming)</a></li>

<li><a href="GRASP_(object-oriented_design)" title="GRASP (object-oriented design)">GRASP (object-oriented designer)</a></li>

<li><a href="Adapter_pattern" title="Adapter pattern">Adapter pattern</a></li>

<li><a href="Strategy_pattern" title="Strategy pattern">Strategy pattern</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFGammaHelmJohnsonVlissides1994" class="citation book cs1"><a href="Erich_Gamma" title="Erich Gamma">Gamma, Erich</a>; <a href="Richard_Helm" title="Richard Helm">Helm, Richard</a>; <a href="Ralph_Johnson_(computer_scientist)" title="Ralph Johnson (computer scientist)">Johnson, Ralph</a>; <a href="John_Vlissides" title="John Vlissides">Vlissides, John</a> (1994). "Template Method". <a href="Design_Patterns" title="Design Patterns"><i>Design Patterns</i></a>. Addison-Wesley. pp. <a rel="nofollow" class="external text" href="https://archive.org/details/designpatternsel00gamm/page/325">325–330</a>. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-201-63361-2</bdi>.</cite></span>

</li>

<li id="cite_note-:2-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-:2_2-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFFreemanFreemanSierraBates2004" class="citation book cs1">Freeman, Eric; Freeman, Elisabeth; Sierra, Kathy; Bates, Bert (2004). Hendrickson, Mike; Loukides, Mike (eds.). <a rel="nofollow" class="external text" href="http://shop.oreilly.com/product/9780596007126.do"><i>Head First Design Patterns</i></a> <span class="cs1-format">(paperback)</span>. Vol. 1. O'REILLY. pp. 289, 311. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-596-00712-6</bdi><span class="reference-accessdate">. Retrieved <span class="nowrap">2012-09-12</span></span>.</cite></span>

</li>

<li id="cite_note-:1-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-:1_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:1_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://sourcemaking.com/design_patterns/template_method">"Template Method Design Pattern"</a>. Source Making - teaching IT professional<span class="reference-accessdate">. Retrieved <span class="nowrap">2012-09-12</span></span>. <q>Template Method is used prominently in frameworks.</q></cite></span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://w3sdesign.com/?gr=b10&ugr=struct">"The Template Method design pattern - Structure"</a>. <i>w3sDesign.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2017-08-12</span></span>.</cite></span>

</li>

<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">LePUS3 legend. Retrieved from <a rel="nofollow" class="external free" href="http://lepus.org.uk/ref/legend/legend.xml">http://lepus.org.uk/ref/legend/legend.xml</a>.</span>

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<li id="cite_note-:3-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-:3_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:3_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-:3_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFChung2011" class="citation book cs1">Chung, Carlo (2011). <i>Pro Objective-C Design Patterns for iOS</i>. Berkeley, CA: Apress. p. 266. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1-4302-3331-2</bdi>.</cite></span>

</li>

<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><cite id="CITEREFVlissides1998" class="citation book cs1">Vlissides, John (1998-06-22). <a rel="nofollow" class="external text" href="http://www.informit.com/store/pattern-hatching-design-patterns-applied-9780201432930"><i>Pattern Hatching: Design Patterns Applied</i></a>. Addison-Wesley Professional. pp. <span class="nowrap">85–</span>101. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0201432930</bdi>.</cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

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<div class="side-box-text plainlist">The Wikibook <i><a href="https://en.wikibooks.org/wiki/Computer_Science_Design_Patterns" class="extiw external" title="wikibooks:Computer Science Design Patterns">Computer Science Design Patterns</a></i> has a page on the topic of: <i><b><a href="https://en.wikibooks.org/wiki/Computer_Science_Design_Patterns/Template_method" class="extiw external" title="wikibooks:Computer Science Design Patterns/Template method">Template method</a></b></i></div></div>

</div>

<ul><li><a rel="nofollow" class="external text" href="https://www.codeproject.com/Articles/307452/common-use-of-Template-Design-pattern-Design-pat">Six common uses of the template pattern</a></li>

<li><a rel="nofollow" class="external text" href="http://sourcemaking.com/design_patterns/template_method">Template Method Design Pattern</a></li></ul>

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</style><div id="Software_design_patterns225" style="font-size:114%;margin:0 4em"><a href="Software_design_pattern" title="Software design pattern">Software design patterns</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Design_Patterns" title="Design Patterns">Gang of Four<br>patterns</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Creational_pattern" title="Creational pattern">Creational</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Abstract_factory_pattern" title="Abstract factory pattern">Abstract factory</a></li>

<li><a href="Builder_pattern" title="Builder pattern">Builder</a></li>

<li><a href="Factory_method_pattern" title="Factory method pattern">Factory method</a></li>

<li><a href="Prototype_pattern" title="Prototype pattern">Prototype</a></li>

<li><a href="Singleton_pattern" title="Singleton pattern">Singleton</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Structural_pattern" title="Structural pattern">Structural</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Adapter_pattern" title="Adapter pattern">Adapter</a></li>

<li><a href="Bridge_pattern" title="Bridge pattern">Bridge</a></li>

<li><a href="Composite_pattern" title="Composite pattern">Composite</a></li>

<li><a href="Decorator_pattern" title="Decorator pattern">Decorator</a></li>

<li><a href="Facade_pattern" title="Facade pattern">Facade</a></li>

<li><a href="Flyweight_pattern" title="Flyweight pattern">Flyweight</a></li>

<li><a href="Proxy_pattern" title="Proxy pattern">Proxy</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Behavioral_pattern" title="Behavioral pattern">Behavioral</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Chain-of-responsibility_pattern" title="Chain-of-responsibility pattern">Chain of responsibility</a></li>

<li><a href="Command_pattern" title="Command pattern">Command</a></li>

<li><a href="Interpreter_pattern" title="Interpreter pattern">Interpreter</a></li>

<li><a href="Iterator_pattern" title="Iterator pattern">Iterator</a></li>

<li><a href="Mediator_pattern" title="Mediator pattern">Mediator</a></li>

<li><a href="Memento_pattern" title="Memento pattern">Memento</a></li>

<li><a href="Observer_pattern" title="Observer pattern">Observer</a></li>

<li><a href="State_pattern" title="State pattern">State</a></li>

<li><a href="Strategy_pattern" title="Strategy pattern">Strategy</a></li>

<li><a href="Visitor_pattern" title="Visitor pattern">Visitor</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Concurrency_pattern" title="Concurrency pattern">Concurrency<br>patterns</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Active_object" title="Active object">Active object</a></li>

<li><a href="Balking_pattern" title="Balking pattern">Balking</a></li>

<li><a href="Binding_properties_pattern" title="Binding properties pattern">Binding properties</a></li>

<li><a href="Double-checked_locking" title="Double-checked locking">Double-checked locking</a></li>

<li><a href="Asynchronous_method_invocation" title="Asynchronous method invocation">Event-based asynchronous</a></li>

<li><a href="Guarded_suspension" title="Guarded suspension">Guarded suspension</a></li>

<li><a href="Monitor_(synchronization)" title="Monitor (synchronization)">Monitor</a></li>

<li><a href="Proactor_pattern" title="Proactor pattern">Proactor</a></li>

<li><a href="Reactor_pattern" title="Reactor pattern">Reactor</a></li>

<li><a href="Readers%E2%80%93writer_lock" title="Readers–writer lock">Read–write lock</a></li>

<li><a href="Scheduler_pattern" class="mw-redirect" title="Scheduler pattern">Scheduler</a></li>

<li><a href="Scheduled-task_pattern" title="Scheduled-task pattern">Scheduled-task pattern</a></li>

<li><a href="Semaphore_(programming)" title="Semaphore (programming)">Semaphore</a></li>

<li><a href="Thread_pool" title="Thread pool">Thread pool</a></li>

<li><a href="Thread-local_storage" title="Thread-local storage">Thread-local storage</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Architectural_pattern" title="Architectural pattern">Architectural<br>patterns</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Front_controller" title="Front controller">Front controller</a></li>

<li><a href="Interceptor_pattern" title="Interceptor pattern">Interceptor</a></li>

<li><a href="Specification_pattern" title="Specification pattern">Specification</a></li>

<li><a href="Publish%E2%80%93subscribe_pattern" title="Publish–subscribe pattern">Publish–subscribe</a></li>

<li><a href="Naked_objects" title="Naked objects">Naked objects</a></li>

<li><a href="Service_locator_pattern" title="Service locator pattern">Service locator</a></li>

<li><a href="Active_record_pattern" title="Active record pattern">Active record</a></li>

<li><a href="Identity_map_pattern" title="Identity map pattern">Identity map</a></li>

<li><a href="Data_access_object" title="Data access object">Data access object</a></li>

<li><a href="Data_transfer_object" title="Data transfer object">Data transfer object</a></li>

<li><a href="Inversion_of_control" title="Inversion of control">Inversion of control</a></li>

<li><a href="JSP_model_2_architecture" title="JSP model 2 architecture">Model 2</a></li>

<li><a href="Broker_pattern" title="Broker pattern">Broker</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other<br>patterns</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Blackboard_design_pattern" class="mw-redirect" title="Blackboard design pattern">Blackboard</a></li>

<li><a href="Business_delegate_pattern" title="Business delegate pattern">Business delegate</a></li>

<li><a href="Composite_entity_pattern" title="Composite entity pattern">Composite entity</a></li>

<li><a href="Dependency_injection" title="Dependency injection">Dependency injection</a></li>

<li><a href="Guard_(computer_science)" title="Guard (computer science)">Guard clause</a></li>

<li><a href="Intercepting_filter_pattern" title="Intercepting filter pattern">Intercepting filter</a></li>

<li><a href="Lazy_loading" title="Lazy loading">Lazy loading</a></li>

<li><a href="Mock_object" title="Mock object">Mock object</a></li>

<li><a href="Null_object_pattern" title="Null object pattern">Null object</a></li>

<li><a href="Object_pool_pattern" title="Object pool pattern">Object pool</a></li>

<li><a href="Servant_(design_pattern)" title="Servant (design pattern)">Servant</a></li>

<li><a href="Type_Tunnel_pattern" class="mw-redirect" title="Type Tunnel pattern">Type tunnel</a></li>

<li><a href="Method_chaining" title="Method chaining">Method chaining</a></li>

<li><a href="Delegation_pattern" title="Delegation pattern">Delegation</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Books</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><i><a href="Design_Patterns" title="Design Patterns">Design Patterns</a></i></li>

<li><i><a href="Enterprise_Integration_Patterns" title="Enterprise Integration Patterns">Enterprise Integration Patterns</a></i></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Christopher_Alexander" title="Christopher Alexander">Christopher Alexander</a></li>

<li><a href="Erich_Gamma" title="Erich Gamma">Erich Gamma</a></li>

<li><a href="Ralph_Johnson_(computer_scientist)" title="Ralph Johnson (computer scientist)">Ralph Johnson</a></li>

<li><a href="John_Vlissides" title="John Vlissides">John Vlissides</a></li>

<li><a href="Grady_Booch" title="Grady Booch">Grady Booch</a></li>

<li><a href="Ward_Cunningham" title="Ward Cunningham">Ward Cunningham</a></li>

<li><a href="Martin_Fowler_(software_engineer)" title="Martin Fowler (software engineer)">Martin Fowler</a></li>

<li><a href="Robert_C._Martin" title="Robert C. Martin">Robert Martin</a></li>

<li><a href="Jim_Coplien" title="Jim Coplien">Jim Coplien</a></li>

<li><a href="Douglas_C._Schmidt" title="Douglas C. Schmidt">Douglas Schmidt</a></li>

<li><a href="Linda_Rising" title="Linda Rising">Linda Rising</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Communities</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="The_Hillside_Group" title="The Hillside Group">The Hillside Group</a></li>

<li><a href="Portland_Pattern_Repository" title="Portland Pattern Repository">Portland Pattern Repository</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">See also</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Anti-pattern" title="Anti-pattern">Anti-pattern</a></li>

<li><a href="Architectural_pattern" title="Architectural pattern">Architectural pattern</a></li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-04-11" href="https://en.wikipedia.org/wiki/?title=Template_method_pattern&oldid=1285035236">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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