public class HashMapDemo
1: //HashMapDemo.java
2: //Illustrates the following HashMap methods:
3: //put()
4: //containsKey()
5: //remove()
6: //keySet()
7: //get()
8:
9: import java.util.HashMap;
10:
11: public class HashMapDemo
12: {
13: public static void main(String[] args)
14: {
15: HashMap<String, Integer> mountains = new HashMap<String, Integer>();
16: mountains.put("Everest",29029);
17: mountains.put("K2",28251);
18: mountains.put("Kangchenjunga",28169);
19: mountains.put("Denali",20335);
20: printMap(mountains);
21:
22: System.out.println("Denali in the map: " +
23: mountains.containsKey("Denali"));
24: System.out.println();
25:
26: System.out.println("Changing height of Denali.");
27: mountains.put("Denali", 20320); // Overwrites the old value for Denali
28: printMap(mountains);
29:
30: System.out.println("Removing Kangchenjunga.");
31: mountains.remove("Kangchenjunga");
32: printMap(mountains);
33:
34: }
35:
36: public static void printMap(HashMap<String, Integer> map)
37: {
38: System.out.println("Map contains:");
39: for (String keyMountainName : map.keySet())
40: {
41: Integer height = map.get(keyMountainName);
42: System.out.println(keyMountainName + " --> " + height.intValue() + " feet.");
43: }
44: System.out.println();
45: }
46: }