MapsDemo.java

packagecollections;

importjava.util.HashMap;
importjava.util.LinkedHashMap;
importjava.util.TreeMap;

publicclassMapsDemo {

publicstaticvoidmain(String[] args) {

System.out.println("HashMap demo\n");
HashMap<Integer, String> map = newHashMap<>();

map.put(5, "testing");
map.put(1, "nirmal");
map.put(2, "rabindra");
map.put(3, "om");
System.out.println(map.entrySet());

System.out.println("size: " + map.size());

System.out.println(map);

System.out.println(map.containsKey(2));

System.out.println(map.containsValue("OM"));
System.out.println(map.containsValue("om"));

System.out.println(map.keySet());

System.out.println(map.values());

System.out.println(map.remove(3));
System.out.println(map);

System.out.println("\nLinkedHashMap demo\n");

LinkedHashMap<Integer, String> lmap = newLinkedHashMap<>();
lmap.put(1, "nirmal");
lmap.put(2, "rabindra");
lmap.put(3, "om");

System.out.println(lmap);
System.out.println(lmap.entrySet());

System.out.println(lmap.keySet());
System.out.println(lmap.values());

System.out.println("\nTreeMap demo\n");

TreeMap<String, String> tmap = newTreeMap<>();

tmap.put("aab", "Hello");
tmap.put("aaa", "First expected");
tmap.put("aad", "last expected");

System.out.println(tmap);
System.out.println(tmap.entrySet());

System.out.println(tmap.lastEntry());

System.out.println(tmap.ceilingKey("aab"));
System.out.println(tmap.ceilingKey("aar"));

// System.out.println(tmap.pollFirstEntry());

System.out.println(tmap);

System.out.println(tmap.subMap("aaa", false, "aar", false));

System.out.println(tmap.tailMap("aab", false));
 }

}