CareerCup

do we need to do anything here when it is only the read operations.

Dont put critical section in synchronized block.

As long as the resource in critical section is immutable, no need to do anything.

static ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
	public void readMethod()
	{
		lock.readLock().lock();
		//read something
		lock.writeLock().unlock();
	}

	public void writeMethod()
	{
		lock.writeLock().lock();
		//read something
		lock.writeLock().unlock();
	}

-> You can use ConcurrentHashMap, which allows multiple reads can happen if no write operation is going on.

-> You can use ConcurrentHashMap, which allows multiple reads can happen if no write operation is going on.

We dont even need a critical section if no one is writing anything.

use read-write lock as in pthreads

readCount=0;
mutex=0;

Reading:

while(writelock == true);
writelock=true;
while(mutex==1);
mutex=1;
readCount++;
mutex=0;

---------
READ
---------

while(mutex==1);
mutex=1;
readCount--;
mutex=0;
writelock=false;




Writing:

while(readLock >0 && writelock==true)
{
writelock=true;
---------
WRITE
---------
writelock=false;
}