1 public class DelSame 
 2 {
 3     public static void main(String[] args) 
 4     {
 5         String str = "AASDDFGFGFGDDD";
 6         char[] c=str.toCharArray();    
 7         for(int i=0;i<c.length-1;i++)
 8         {
 9             for(int j=i+1;j<c.length;i++)
10             {
11                 if(c[i]==c[j])
12                 {
13                     c[j]=' ';
14                 }
15             }
16         }
17         for(char x:c)
18         {
19             System.out.println(x);
20         }
21         
22     }
23 }

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 17
at test01.DelSame.main(DelSame.java:13)