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tigraboris
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changes fixing mistakes
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‎pom.xml

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<module>event-sourcing</module>
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<module>data-transfer-object</module>
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<module>throttling</module>
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<module>unit-of-work</module>
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<module>partial-response</module>
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<module>eip-wire-tap</module>
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<module>eip-splitter</module>
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<module>eip-aggregator</module>
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<module>retry</module>
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<module>trampoline</module>
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</modules>
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<repositories>

‎trampoline/README.md

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---
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## Intent
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By representing a computation in one of 2 states
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Trampoline pattern is used for implementing algorithms recursively in Java without blowing the stack
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and to interleave the execution of functions without hard coding them together
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It is possible by representing a computation in one of 2 states : done | more
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(completed with result, or a reference to the reminder of the computation,
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something like the way a java.util.Supplier does)
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it is possible to implement algorithms recursively in Java without blowing the stack
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and to interleave the execution of functions without hard coding them together or even using threads.
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something like the way a java.util.Supplier does).
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## Explanation
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Trampoline pattern allows to define recursive algorithms by iterative loop.
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## Applicability
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Use the Trampoline pattern when
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Trampolines in Java usually involve the creation of a GenericListener to pass events to an outer class.
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## Credits
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## Tutorials
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* [Trampolining: a practical guide for awesome Java Developers](https://medium.com/@johnmcclean/trampolining-a-practical-guide-for-awesome-java-developers-4b657d9c3076)
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* [Trampoline in java ](http://mindprod.com/jgloss/trampoline.html)
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* [cyclops-react](https://github.com/aol/cyclops-react)
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## Credits
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* [library 'cyclops-react' uses the pattern](https://github.com/aol/cyclops-react)
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‎trampoline/pom.xml

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</parent>
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<artifactId>trampoline</artifactId>
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<dependencies>
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<!-- https://mvnrepository.com/artifact/junit/junit -->
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<dependency>
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<groupId>junit</groupId>
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<artifactId>junit</artifactId>
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<version>4.12</version>
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<scope>test</scope>
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</dependency>
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<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
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<dependency>
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<groupId>org.projectlombok</groupId>
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<artifactId>lombok</artifactId>
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<version>1.16.18</version>
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<scope>provided</scope>
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</dependency>
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‎trampoline/src/main/java/com/iluwatar/trampoline/Trampoline.java

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import java.util.stream.Stream;
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/**When get is called on the returned Trampoline, internally it will iterate calling ‘jump’
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on the returned Trampoline as long as the concrete instance returned is More,
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stopping once the returned instance is Done. Essential we convert looping via recursion into iteration,
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the key enabling mechanism is the fact that Trampoline.more is a lazy operation.
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Trampoline in cyclops-react extends java.util.Supplier. Calling Trampoline.more we are basically creating
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a Supplier that defers the actual recursive call, and having defered the call we can move it outside of the recursive loop.
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This means we can define algorithms recursively in Java but execute them iteratively.*/
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/**<p>Trampoline pattern allows to define recursive algorithms by iterative loop </p>
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* <p>When get is called on the returned Trampoline, internally it will iterate calling ‘jump’
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on the returned Trampoline as long as the concrete instance returned is {@link #more(Trampoline)},
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stopping once the returned instance is {@link #done(Object)}.</p>
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<p>Essential we convert looping via recursion into iteration,
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the key enabling mechanism is the fact that {@link #more(Trampoline)} is a lazy operation.</p>
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*/
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public interface Trampoline<T> {
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T get();

‎trampoline/src/main/java/com/iluwatar/trampoline/TrampolineApp.java

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/**
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* The MIT License
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* Copyright (c) 2014-2016 Ilkka Seppälä
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*
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* <p>
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* <p>
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* <p>
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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import lombok.extern.slf4j.Slf4j;
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/**
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* <div>
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* By representing a computation in one of 2 states
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(completed with result, or a reference to the reminder of the computation,
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something like the way a java.util.Supplier does)
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it is possible to implement algorithms recursively in Java without blowing the stack
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and to interleave the execution of functions without hard coding them together or even using threads.
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</div>
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<div>
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Trampoline has 2 state : [done], [ more]
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</div>
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When get is called on the returned Trampoline, internally it will iterate calling ‘jump’
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on the returned Trampoline as long as the concrete instance returned is More,
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stopping once the returned instance is Done. Essential we convert looping via recursion into iteration,
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the key enabling mechanism is the fact that Trampoline.more is a lazy operation.
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Trampoline in cyclops-react extends java.util.Supplier. Calling Trampoline.more we are basically creating
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a Supplier that defers the actual recursive call, and having defered the call we can move it outside of the recursive loop.
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This means we can define algorithms recursively in Java but execute them iteratively.
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* <p>Trampoline pattern allows to define recursive algorithms by iterative loop </p>
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* <p>it is possible to implement algorithms recursively in Java without blowing the stack
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* and to interleave the execution of functions without hard coding them together or even using threads.</p>
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*/
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@Slf4j
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public class TrampolineApp {
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public static void main(String[] args) {
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log.info("start pattern");
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Integer result = loop(10, 1).result();
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log.info("result {}" ,result);
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log.info("result {}", result);
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}
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/**
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* Manager for pattern.
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* Manager for pattern. Define it with a factorial function.
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* */
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public static Trampoline<Integer> loop(int times,int prod){
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if(times==0)
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public static Trampoline<Integer> loop(int times, int prod) {
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if (times == 0)
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return Trampoline.done(prod);
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else
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return Trampoline.more(()->loop(times-1,prod*times));
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return Trampoline.more(() -> loop(times - 1, prod * times));
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}
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}

‎trampoline/src/test/java/com/iluwatar/trampoline/TrampolineAppTest.java

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public class TrampolineAppTest {
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@Test
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public void test()throws IOException{
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public void testTrampolineWithFactorialFunction()throws IOException{
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int result = TrampolineApp.loop(10, 1).result();
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assertEquals("Be equal",3628800,result);
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}

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