$1.$ In the driver, exercise twelve various insersion and deletion operations.

$2.$If duplication is found for inserion, the program provides a message, and does not insert duplicated magzine.

$3.$ If no title is found in deletion operation, the program provides a message, and does not delete any magazin.

Code:

public class MagazineList

$\{$

private MagazineNode list;

$//---------------------------------------------------------$

$-------$

$//$ Sets up an initially empty list of magazines.

$//---------------------------------------------------------$

$-------$

public MagazineList$()$

$\{$

list $=$ null;

$\}$

$//---------------------------------------------------------$

$-------$

$//$ Creates a new MagazineNode object and adds it to the

end of

$//$ the linked list.

$//---------------------------------------------------------$

$-------$

public void add$($Magazine mag$)$

$\{$

MagazineNode node $=$ new MagazineNode$($mag$)$;

MagazineNode current;

if $($list $==$ null$)$

list $=$ node;

else

$\{$

current $=$ list;

while $($current$.$next $!=$ null$)$

current $=$ current.next;

current.next $=$ node;

$\}$

$\}$

$//------------------------------------------------------------$

$----$

$//$ Returns this list of magazines as a string.

$//------------------------------------------------------------$

$----$

public String toString$()$

$\{$

String result $=""$;

MagazineNode current $=$ list;

while $($current $!=$ null$)$

$\{$

result $+=$ current.magazine $+"$

$"$;

current $=$ current.next;

$\}$

return result;

$\}$

$//*****************************************************************$

$//$ An inner class that represents a node in the magazine

list.

$//$ The public variables are accessed by the MagazineList

class.

$//*****************************************************************$

private class MagazineNode

$\{$

public Magazine magazine;

public MagazineNode next;

$//------------------------------------------------------$

$--------$

$//$ Sets up the node

$//------------------------------------------------------$

$--------$

public MagazineNode$($Magazine mag$)$

$\{$

magazine $=$ mag;

next $=$ null;

$\}$

$\}$

$\}$