package sync;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.Semaphore;

public class Test $\{$

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

ExecutorService executorService $=$ Executors.newCachedThreadPool$()$;

ReadWriteLock RW $=$ new ReadWriteLock$()$;

executorService.execute$($new Writer$($RW$))$;

executorService.execute$($new Writer$($RW$))$;

executorService.execute$($new Writer$($RW$))$;

executorService.execute$($new Writer$($RW$))$;

executorService.execute$($new Reader$($RW$))$;

executorService.execute$($new Reader$($RW$))$;

executorService.execute$($new Reader$($RW$))$;

executorService.execute$($new Reader$($RW$))$;

$\}$

$\}$

class ReadWriteLock$\{$

private Semaphore S$=$new Semaphore$(1)$;

public void readLock$()\{$

$\}$

public void writeLock$()\{$

$\}$

public void readUnLock$()\{$

$\}$

public void writeUnLock$()\{$

$\}$

$\}$

class Writer implements Runnable

$\{$

private ReadWriteLock RW$\_$lock;

public Writer$($ReadWriteLock rw$)\{$

RW$\_$lock $=$ rw;

$\}$

public void run$()\{$

while $($true$)\{$

RW$\_$lock.writeLock$()$;

RW$\_$lock.writeUnLock$()$;

$\}$

$\}$

$\}$

class Reader implements Runnable

$\{$

private ReadWriteLock RW$\_$lock;

public Reader$($ReadWriteLock rw$)\{$

RW$\_$lock $=$ rw;

$\}$

public void run$()\{$

while $($true$)\{$

RW$\_$lock.readLock$()$;

RW$\_$lock.readUnLock$()$;

$\}$

$\}$

$\}$

this is the test.java mentioned in the question.