treemap in java

1import java.util.ArrayList;
2import java.util.Collections;
3import java.util.List;
4import java.util.ListIterator;
5public class Main {
6   public static void main(String[] args) {
7      List<String> list = new ArrayList<String>();
8      list.add("a");
9      list.add("b");
10      list.add("c");
11      list.add("d");
12      list.add("e");
13      list.add("f");
14      
15      //On met la liste dans le désordre
16      Collections.shuffle(list);
17      System.out.println(list);
18      
19      //On la remet dans l'ordre
20      Collections.sort(list);
21      System.out.println(list);
22      
23      Collections.rotate(list, -1);
24      System.out.println(list);
25      
26      //On récupère une sous-liste
27      List<String> sub = list.subList(2, 5);
28      System.out.println(sub);
29      Collections.reverse(sub);
30      System.out.println(sub);
31      
32      //On récupère un ListIterator
33      ListIterator<String> it = list.listIterator();
34      while(it.hasNext()){
35         String str = it.next();
36         if(str.equals("d"))
37            it.set("z");
38      }
39      while(it.hasPrevious())
40         System.out.print(it.previous());
41      
42   }
43}
44

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