public  void close() throws Exception
Closes this resource, relinquishing any underlying resources.
This method is invoked automatically on objects managed by the
{@code try}-with-resources statement.

While this interface method is declared to throw {@code
Exception}, implementers are strongly encouraged to
declare concrete implementations of the {@code close} method to
throw more specific exceptions, or to throw no exception at all
if the close operation cannot fail.

Implementers of this interface are also strongly advised
to not have the {@code close} method throw InterruptedException .

This exception interacts with a thread's interrupted status,
and runtime misbehavior is likely to occur if an {@code
InterruptedException} is {@linkplain Throwable#addSuppressed
suppressed}.

More generally, if it would cause problems for an
exception to be suppressed, the {@code AutoCloseable.close}
method should not throw it.

Note that unlike the  close 
method of java.io.Closeable , this {@code close} method
is not required to be idempotent.  In other words,
calling this {@code close} method more than once may have some
visible side effect, unlike {@code Closeable.close} which is
required to have no effect if called more than once.

However, implementers of this interface are strongly encouraged
to make their {@code close} methods idempotent.