Implement a Java program that creates two new threads that are in a race condi$-$ tion. Use the problem from slide $6-6$ and $6-7$ as example, however you do not use a spooler directory, i$.$e$.$ just increment a shared variable in by copying it into a variable next$\_$free$\_$slot that is local to each thread $($comparable to a CPU register $$ in fact the Java compiler$/$virtual machine likely use a CPU register for that local variable$),$ incrementing that variable by $1,$ and writing it back to in$.$

in shall be initialised with $0.$ Each of the two threads shall increment the in in a loop using the same number of iterations $($the number is passed in as command line parameter$)$ and terminate after that number of incrementations. Use the join$()$ method to wait for the termination of the two threads. After that, the value of in is printed out.

As starting point, use the files from tol$401$g$\_$assignment$11.$zip that you find in Canvas

$$ File Assignment$11.$java contains the main method that reads the number of iter$-$ ations to be executed by each thread and prints the result out $$ do not change that file!

$$ Use file MyAssignment$11.$java to add your implementation there $($it gets called by file Assignment$11.$java$).$ Feel free to change that file except:

$($a$)$ Do not change the name of this class $($adding extends is OK$)$ nor put it into another package.

$($b$)$ Do not modify the name and input and output parameter of the main method.

$$ You are allowed to add further classes.

Hints:

$$ As each thread is executed by $($or within$)$ two different objects $($created by you via new$),$ it is not sufficient to define in as ordinary field $($outside of Java, fields are known as attributes$)$ within the two thread objects. The object$-$oriented concept of encapsulation requires to define the shared variable either as static so that it is shared by all instances of that class or to introduce a separate class $($e$.$g$.$ named Counter with, e$.$g$.,$ a method increment$())$ or a public in variable which are instantiated by you and passed to both thread instances.

$$ Depending on how threads are scheduled on your machine, the data type int may not be large enough to provoke a race condition, hence you better use the data type long for your counters and number of iterations variables.

$$ You need to define your variable that is shared by the threads as volatile $($see slide $6-41),$ e$.$g$.$ volatile long in$.2.$ Run your program: is the printed value of in the expected value? How would you see that a race condition occurred?

$3.$ What command line parameter value demonstrates typically at each run the race con$-$ dition on your computer? What is the name and version of your OS $($e$.$g$.$MS Windows $10)?//$ You are free to modify this class, e$.$g$.$ add fields, methods,

$//$ constructors, extend from class Thread etc. with the two exceptions:

$//1.$ Do not change the name of this class nor put it into another package

$//2.$ Do not modify the name and input and output parameter of the main method.

public class MyAssignment$11\{//$ TODO: Modify as necessary

$//$ TODO: fill in your code here

public static long main$($long iterationsPerThread$)\{//$ Do not modify this line!

$//$ TODO: fill in your code here

$\}$

$\}$

$//$ Any modifications to this file will be ignored.

public class Assignment$11\{$

public static void main$($String$[]$ args$)\{$

if $($args$.$length $1)\{$

System.out.println$("$One command line parameter only: must be an interger $($or long$)$ number"$)$;

$\}$ else $\{$

long iterationsPerThread $=$ Long.parseLong$($args$[0])$;

$//$ Call to student's class:

$//$ takes number of iterations per thread as input

$//$ returns result of two threads each incrementing a shared

$//$ variable $"$in$"($initialised with $0)$ "iterationsPerThread" times.

long result $=$ MyAssignment$11.$main$($iterationsPerThread$)$;

System.out.println$($result$)$;

$\}$

$\}$

$\}$