leetcode--Simplify Path

Given an absolute path for a file (Unix-style), simplify it.

For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"

click to show corner cases.

Corner Cases:

 

• Did you consider the case where path = "/../"?
  In this case, you should return "/".
• Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
  In this case, you should ignore redundant slashes and return "/home/foo".

public class Solution {
    public String simplifyPath(String path) {
        StringBuffer pathaccu= new StringBuffer();
        if(path == null || path.length() == 0)
            return pathaccu.toString();

        String[] splits = path.split("/");
        Stack<String> st = new Stack<String>();
        for(int i = 0; i < splits.length; ++i){
            if(splits[i].equals("..")){
                if(!st.empty())
                    st.pop();
            }
            else if(splits[i].equals(".") || splits[i].equals("")){
                //do nothing
            }
            else
                st.push(splits[i]);
        }
        if(st.empty())
            pathaccu.append("/");
        else{
            while(!st.empty())
                pathaccu.insert(0, "/"+st.pop());
            //pathaccu.insert(0,"/");
        }
        return pathaccu.toString();
    }
}