Creates a new ThreadPoolExecutor with the given initial parameters, the default thread factory and the default rejected execution handler.

It may be more convenient to use one of the Executors factory methods instead of this general purpose constructor.

Parameters:

corePoolSize		the number of threads to keep in the pool, even if they are idle, unless allowCoreThreadTimeOut is set
maximumPoolSize		the maximum number of threads to allow in the pool
keepAliveTime		when the number of threads is greater than the core, this is the maximum time that excess idle threads will wait for new tasks before terminating.
unit		the time unit for the keepAliveTime argument
workQueue		the queue to use for holding tasks before they are executed. This queue will hold only the Runnable tasks submitted by the execute method.

Exceptions:

IllegalArgumentException		if one of the following holds: corePoolSize < 0 keepAliveTime < 0 maximumPoolSize <= 0 maximumPoolSize < corePoolSize
NullPointerException		if workQueue is null