34 lines
1.0 KiB
Java
34 lines
1.0 KiB
Java
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package com.iluwatar;
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/**
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*
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* Lazy loading idiom defers object creation until needed.
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*
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* This example shows different implementations of the pattern
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* with increasing sophistication.
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*
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* 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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*/
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public class App
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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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HolderNaive holderNaive = new HolderNaive();
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Heavy heavy = holderNaive.getHeavy();
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System.out.println("heavy=" + heavy);
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// Thread safe lazy loader, but with heavy synchronization on each access
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HolderThreadSafe holderThreadSafe = new HolderThreadSafe();
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Heavy another = holderThreadSafe.getHeavy();
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System.out.println("another=" + another);
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// The most efficient lazy loader utilizing Java 8 features
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Java8Holder java8Holder = new Java8Holder();
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Heavy next = java8Holder.getHeavy();
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System.out.println("next=" + next);
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}
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}
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