48 lines
823 B
Java
48 lines
823 B
Java
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package com.iluwatar.dirtyflag;
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import java.util.ArrayList;
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import java.util.List;
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/**
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*
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* A middle-layer app that calls/passes along data from the back-end.
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*
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* @author swaisuan
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*
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*/
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public class World {
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private static World world;
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private static List<String> countries = new ArrayList<String>();
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private World() {
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}
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/**
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* Init.
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*
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* @return World instance
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*/
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public static World getInstance() {
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if (world == null) {
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world = new World();
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}
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return world;
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}
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/**
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*
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* Calls {@link DataFetcher} to fetch data from back-end.
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*
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* @return List of strings
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*/
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public List<String> fetch() {
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DataFetcher df = DataFetcher.getInstance();
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List<String> data = df.fetch();
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countries = data == null ? countries : data;
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return countries;
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}
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}
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