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HashtableDemo.javaAPI DocExample1421Sat Oct 26 09:53:56 BST 2002None

HashtableDemo

public class HashtableDemo extends Object
Demonstrate the Hashtable class, and an Enumeration.
see
HashMapDemo, for the newer HashMap class.

Fields Summary
Constructors Summary
Methods Summary
public static voidmain(java.lang.String[] argv)


		// Construct and load the hash. This simulates loading a
		// database or reading from a file, or wherever the data is.

		Hashtable h = new Hashtable();

		// The hash maps from company name to address.
		// In real life this might map to an Address object...
		h.put("Adobe", "Mountain View, CA");
		h.put("IBM", "White Plains, NY");
		h.put("Learning Tree", "Los Angeles, CA");
		h.put("Microsoft", "Redmond, WA");
		h.put("Netscape", "Mountain View, CA");
		h.put("O'Reilly", "Sebastopol, CA");
		h.put("Sun", "Mountain View, 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)h.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)
		Enumeration k = h.keys();
		while (k.hasMoreElements()) {
			String key = (String) k.nextElement();
			System.out.println("Key " + key + "; Value " +
				(String) h.get(key));
		}