Java TreeMap Ascending | Descending

1. import  java.util.Comparator;  
2. import  java.util.TreeMap;  
3. public class  Main {   
4.     publicstaticvoid main(String[] args) {    
5.         TreeMap<Integer,Integer> map1 =  new  TreeMap<Integer,Integer>();   //The default TreeMap is sorted in ascending order  
6.         TreeMap<Integer,Integer> map2= new TreeMap<Integer,Integer>(new Comparator<Integer>(){  
7.              /*  
8.              * int compare(Object o1, Object o2) returns a primitive integer,  
9.              * Return a negative number to indicate: o1 is less than o2,  
10.              * Return 0 means: o1 and o2 are equal,  
11.              * Returns a positive number indicating: o1 is greater than o2.  
12.              */    
13.             publicint compare(Integer a,Integer b){   
14.                 return b-a;           
15.             }  
16.             });  
17.         map2.put(1,2);  
18.         map2.put(2,4);  
19.         map2.put(7, 1);  
20.         map2.put(5,2);  
21.         System.out.println("Map2="+map2);    
22.           
23.         map1.put(1,2);  
24.         map1.put(2,4);  
25.         map1.put(7, 1);  
26.         map1.put(5,2);  
27.         System.out.println("map1="+map1);  
28.     }  
29.       
30.       
31.       
32.       
33. }