What you can do with a TreeMap : HashTable Map : Collections Data Structure : Java examples (example source code) Organized by topic






// : c11:SortedMapDemo.java

//What you can do with a TreeMap.

//From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002

//www.BruceEckel.com. See copyright notice in CopyRight.txt.



import java.util.Iterator;

import java.util.TreeMap;



public class SortedMapDemo {



  public static void main(String[] args) {

    TreeMap sortedMap = new TreeMap();

    sortedMap.put("Adobe", "Mountain View, CA");

    sortedMap.put("IBM", "White Plains, NY");

    sortedMap.put("Learning Tree", "Los Angeles, CA");

    sortedMap.put("Microsoft", "Redmond, WA");

    sortedMap.put("Netscape", "Mountain View, CA");

    sortedMap.put("O'Reilly", "Sebastopol, CA");

    sortedMap.put("Sun", "Mountain View, CA");

    System.out.println(sortedMap);

    Object low = sortedMap.firstKey(), high = sortedMap.lastKey();

    System.out.println(low);

    System.out.println(high);

    Iterator it = sortedMap.keySet().iterator();

    for (int i = 0; i <= 6; i++) {

      if (i == 3)

        low = it.next();

      if (i == 6)

        high = it.next();

      else

        it.next();

    }

    System.out.println(low);

    System.out.println(high);

    System.out.println(sortedMap.subMap(low, high));

    System.out.println(sortedMap.headMap(high));

    System.out.println(sortedMap.tailMap(low));

  }

} ///:~


1. Associates keys with values
2. A simple Map implementation
3. Hash table with separate chaining
4. Hash table with linear probing
5. Hash table with double hashing
6. Working with Key-Value Pairs in a Hashtable
7. Demonstrate the Hashtable class, and an Enumeration
8. Demonstrate the HashMap class, and an Iterator
9. Soft HashMap
10. MultiMap extends AbstractMap
11. Array Map extends AbstractMap
12. Demonstrating the WeakHashMap
13. Use treemap
14. Sorting Elements in a TreeMap
15. A Map implemented with ArrayLists
16. Simple demonstration of HashMap