[LeetCode]71 Simplify Path

public class Solution {
public String simplifyPath(String path) {
if (path == null)
return null;

String[] paths = path.split("/");

Stack<String> stack = new Stack<>();
for (String p : paths)
{
if (p.equals(".") || p.isEmpty())
{
continue;
}

if (p.equals(".."))
{
if (!stack.empty())
stack.pop();
}
else
{
stack.push(p);
}
}

if (stack.empty())
return "/"; // No path

StringBuilder sb = new StringBuilder();
while (!stack.empty())
{
sb.insert(0, "/" + stack.pop());
}
return sb.toString();
}
}