5cf2fe009b
* Use lombok, reformat, and optimize the code * Fix merge conflicts and some sonar issues Co-authored-by: va1m <va1m@email.com>
62 lines
2.2 KiB
Java
62 lines
2.2 KiB
Java
/*
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* The MIT License
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* Copyright © 2014-2021 Ilkka Seppälä
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*
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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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* 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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* 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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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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package com.iluwatar.lazy.loading;
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import lombok.extern.slf4j.Slf4j;
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/**
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* Lazy loading idiom defers object creation until needed.
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*
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* <p>This example shows different implementations of the pattern with increasing sophistication.
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*
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* <p>Additional information and lazy loading flavours are described in
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* http://martinfowler.com/eaaCatalog/lazyLoad.html
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*/
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@Slf4j
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public class App {
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/**
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* Program entry point.
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*
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* @param args command line args
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*/
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public static void main(String[] args) {
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// Simple lazy loader - not thread safe
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var holderNaive = new HolderNaive();
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var heavy = holderNaive.getHeavy();
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LOGGER.info("heavy={}", heavy);
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// Thread safe lazy loader, but with heavy synchronization on each access
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var holderThreadSafe = new HolderThreadSafe();
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var another = holderThreadSafe.getHeavy();
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LOGGER.info("another={}", another);
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// The most efficient lazy loader utilizing Java 8 features
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var java8Holder = new Java8Holder();
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var next = java8Holder.getHeavy();
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LOGGER.info("next={}", next);
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}
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}
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