45 lines
619 B
Java
45 lines
619 B
Java
package com.iluwatar.nullobject;
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/**
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*
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* Null Object implementation for binary tree node.
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*
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* Implemented as Singleton, since all the NullNodes are the same.
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*
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*/
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public class NullNode implements Node {
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private static NullNode instance = new NullNode();
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private NullNode() {
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}
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public static NullNode getInstance() {
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return instance;
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}
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@Override
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public int getTreeSize() {
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return 0;
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}
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@Override
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public Node getLeft() {
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return null;
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}
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@Override
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public Node getRight() {
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return null;
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}
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@Override
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public String getName() {
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return null;
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}
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@Override
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public void walk() {
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}
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}
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