how is java treemap implemented code example

Example 1: TreeMap in java

import java.util.Map;
import java.util.TreeMap;
public class TreeMapExample
{
   public static void main(String[] args) 
   {
      TreeMap<Integer, String> tm = new TreeMap<Integer, String>();    
      tm.put(1000, "Apple");    
      tm.put(1002, "Raspberry");    
      tm.put(1001, "Velvet apple");    
      tm.put(1003, "Banana");    
      for(Map.Entry obj : tm.entrySet())
      {    
         System.out.println(obj.getKey() + " " + obj.getValue());    
      }
   }
}

Example 2: java treemap

import java.util.*;

// Declare the variable using the interface of the object for flexibility.
// Non-primative data types only.
Map<Integer, String> mambo = new TreeMap<Integer, String>();

mambo.put(key, value);
// TreeMap will be sorted by key.
// Work with any comparable object as a key.

mambo.put(1, "Monica");
mambo.put(2, "Erica");
mambo.put(3, "Rita");