[Tex/LaTex] Create Double line Border in table

Question

Here, i have simple latex code which generate simple table. However, i want double lined border in my table. How can i generate that?

\begin{table}[]
\centering
\caption{My caption}
\label{my-label}
\begin{tabular}{|l|l|l|}
\hline
x & x & x \\ \hline
x & x & x \\ \hline
x & x & x \\ \hline
x & x & x \\ \hline
\end{tabular}
\end{table}

Please help me out.

I want table like below,

Answer 1

Since both frames are using thicker lines than the normal table lines, two nested \fbox commands solves the issue:

\documentclass{article}
\usepackage{caption}
\begin{document}
\begin{table}
\centering
\caption{My caption}
\label{my-label}
\setlength{\fboxrule}{1pt}
\setlength{\fboxsep}{\doublerulesep}
\fbox{%
  \setlength{\fboxsep}{0pt}%
  \fbox{%
    \begin{tabular}{l|l|l}
    x & x & x \\ \hline
    x & x & x \\ \hline
    x & x & x \\ \hline
    x & x & x \\
    \end{tabular}%
  }%
}
\end{table}
\end{document}

For nicer tables, see ilFuria's comment.