33 lines
762 B
Java
33 lines
762 B
Java
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package com.iluwatar;
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/**
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*
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* Null Object pattern replaces null values with neutral objects.
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* Many times this simplifies algorithms since no extra null checks
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* are needed.
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*
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* In this example we build a binary tree where the nodes are either
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* normal or Null Objects. No null values are used in the tree making
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* the traversal easy.
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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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Node root = new NodeImpl("1",
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new NodeImpl("11",
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new NodeImpl("111",
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new NullNode(),
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new NullNode()),
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new NullNode()),
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new NodeImpl("12",
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new NullNode(),
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new NodeImpl("122",
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new NullNode(),
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new NullNode())));
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root.walk();
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}
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}
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