A tutorial on sorted maps in Java, plus some explanation of the Map interface and interfaces in general.

After starting the video, click the maximise button to make it fullscreen so you can see the code!

Code For This Tutorial

App.java:

import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.TreeMap;

public class App {

	public static void main(String[] args) {
		Map<Integer, String> hashMap = new HashMap<Integer, String>();
		Map<Integer, String> linkedHashMap = new LinkedHashMap<Integer, String>();
		Map<Integer, String> treeMap = new TreeMap<Integer, String>();
		
		testMap(treeMap);
	}
	
	public static void testMap(Map<Integer, String> map) {
		map.put(9, "fox");
		map.put(4, "cat");
		map.put(8, "dog");
		map.put(1, "giraffe");
		map.put(0, "swan");
		map.put(15, "bear");
		map.put(6, "snake");
		
		for(Integer key: map.keySet()) {
			String value = map.get(key);
			
			System.out.println(key + ": " + value);
		}
	}
	
}

0: swan
1: giraffe
4: cat
6: snake
8: dog
9: fox
15: bear

All pages on this site are copyright © 2013 John W. Purcell