java treemap

1import java.util.Map;
2import java.util.TreeMap;
3public class TreeMapExample
4{
5   public static void main(String[] args) 
6   {
7      TreeMap<Integer, String> tm = new TreeMap<Integer, String>();    
8      tm.put(1000, "Apple");    
9      tm.put(1002, "Raspberry");    
10      tm.put(1001, "Velvet apple");    
11      tm.put(1003, "Banana");    
12      for(Map.Entry obj : tm.entrySet())
13      {    
14         System.out.println(obj.getKey() + " " + obj.getValue());    
15      }
16   }
17}

1import java.util.*;
2
3// Declare the variable using the interface of the object for flexibility.
4// Non-primative data types only.
5Map<Integer, String> mambo = new TreeMap<Integer, String>();
6
7mambo.put(key, value);
8// TreeMap will be sorted by key.
9// Work with any comparable object as a key.
10
11mambo.put(1, "Monica");
12mambo.put(2, "Erica");
13mambo.put(3, "Rita");

1- TreeMap doesn't have null key and keys are sorted
2 Can contain only unique keys and keys are sorted in ascending order.
3

1TreeMap<Integer, String> x = new TreeMap<Integer, String>();    
2tm.put(1, "Hello");

1TreeSet: Can contain only unique values and it is sorted in ascending order
2TreeMap: Can contain only unique keys and keys are sorted in ascending order.
3