// Construct and load the hash. This simulates loading a
// database or reading from a file, or wherever the data is.
Map map = new MyMap();
// The hash maps from company name to address.
// In real life this might map to an Address object...
map.put("Adobe", "Mountain View, CA");
map.put("Learning Tree", "Los Angeles, CA");
map.put("IBM", "White Plains, NY");
map.put("Netscape", "Mountain View, CA");
map.put("Microsoft", "Redmond, WA");
map.put("Sun", "Mountain View, CA");
map.put("O'Reilly", "Sebastopol, CA");
// Two versions of the "retrieval" phase.
// Version 1: get one pair's value given its key
// (presumably the key would really come from user input):
String queryString = "O'Reilly";
System.out.println("You asked about " + queryString + ".");
String resultString = (String)map.get(queryString);
System.out.println("They are located in: " + resultString);
System.out.println();
// Version 2: get ALL the keys and pairs
// (maybe to print a report, or to save to disk)
Iterator k = map.keySet().iterator();
while (k.hasNext()) {
String key = (String) k.next();
System.out.println("Key " + key + "; Value " +
(String) map.get(key));
}
// Step 3 - try out the entrySet() method.
Set es = map.entrySet();
System.out.println("entrySet() returns " + es.size() + " Map.Entry's");
