[Leetcode] Simplify Path

 1 public class Solution {
 2     public String simplifyPath(String path) {
 3         if(path==null||path.length()==0)
 4             return "";
 5         if(path.equals("/"))
 6             return "/";
 7         String[] tokens=path.split("/");
 8         Stack<String> stack=new Stack<String>();
 9         
10         for(int i=0;i<tokens.length;++i){
11             if(tokens[i].equals("..")){
12                 if(!stack.empty())
13                     stack.pop();
14                 else
15                     continue;
16             }else if(tokens[i].equals(".")||tokens[i].length()==0){
17                 continue;
18             }else{
19                 stack.push(tokens[i]);
20             }
21         }
22         
23         Stack<String> stack2=new Stack<String>();
24         String result=new String("");
25         
26         if(stack.empty())
27             return "/";
28         
29         while(!stack.empty())
30             stack2.push(stack.pop());
31         while(!stack2.empty()){
32             result+="/";
33             result+=stack2.pop();
34         }
35         return result;   
36     }
37 }