71. Simplify Path

class Solution {
    public String simplifyPath(String path) {
        Deque<String> stack = new ArrayDeque<>();
        String[] components = path.split("/");
        for (String directory : components) {
            if (directory.equals(".") || directory.equals("")) {
                continue;
            } else if (directory.equals("..")) {
                if (!stack.isEmpty()) {
                    stack.pop();
                }
            } else {
                stack.push(directory);
            }
        }
        
        StringBuilder sb = new StringBuilder();
        while (! stack.isEmpty()) {
            sb.insert(0, stack.pop());
            sb.insert(0, "/");
        }
        return sb.length() > 0 ? sb.toString() : "/";
    }
}