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Hemant Bothra 310ae50248 Issue 989 final-batch (#1119) 
* Adding support for maven assembly plugin to generate executable jar with all dependencies in built

* Merge branch 'master' into issue-989

# Conflicts:
#	abstract-document/pom.xml
#	pom.xml

* Adding maven assemly plugin for projects with name A

* Update in format as per checkstyle, i.e. Spcae in place of tab with size of 2

* batch set - 2 having all project with B and C

* issue-989 d-e-f

* fixing eip pom and adding g-h-i-l-m-n Skipping naked object as it seems it doesn't have main method, will consider this at end

* Adding for O and P projects Skipping Object-Mother as we don't have main method for same.

* Final batch
2019-12-29 14:41:21 +02:00
..
etc
#1113 Add uml-reverse-mapper plugin
2019-12-07 18:03:49 +02:00
src
Java 11 migration: patterns (t-v) (#1085)
2019-11-14 07:42:05 +02:00
pom.xml
Issue 989 final-batch (#1119)
2019-12-29 14:41:21 +02:00
README.md
https://github.com/iluwatar/java-design-patterns-web/issues/8 Fix typo in tag
2019-12-13 22:22:11 +02:00

README.md

layout, title, folder, permalink, categories, tags
layout title folder permalink categories tags
pattern Template method template-method /patterns/template-method/ Behavioral
Gang of Four

Intent

Define the skeleton of an algorithm in an operation, deferring some steps to subclasses. Template method lets subclasses redefine certain steps of an algorithm without changing the algorithm's structure.

To make sure that subclasses don’t override the template method, the template method should be declared final.

Class diagram

alt text

Applicability

The Template Method pattern should be used

  • To implement the invariant parts of an algorithm once and leave it up to subclasses to implement the behavior that can vary
  • When common behavior among subclasses should be factored and localized in a common class to avoid code duplication. This is good example of "refactoring to generalize" as described by Opdyke and Johnson. You first identify the differences in the existing code and then separate the differences into new operations. Finally, you replace the differing code with a template method that calls one of these new operations
  • To control subclasses extensions. You can define a template method that calls "hook" operations at specific points, thereby permitting extensions only at those points

Tutorial

Real world examples

  • javax.servlet.GenericServlet.init: Method GenericServlet.init(ServletConfig config) calls the parameterless method GenericServlet.init() which is intended to be overridden in subclasses. Method GenericServlet.init(ServletConfig config) is the template method in this example.

Credits