Consider the following code on Singleton to answer below questions:

public class Driver $\{$

private static Driver instance;

private Driver$()\{\}$

public static synchronized Driver getInstance$()\{$

if$($instance $==$ null$)\{$ instance $=$ new Driver$()$; $\}$

return instance;

$\}$

$\}$

Which OO basics is used by the Singleton pattern, justify your answer?

Can we consider the instance of Driver in the above code thread$-$safe? Explain your answer?

What is the issue with this code?

rewrite the above code to make it better based on your answer in $3$