if(log.isInfoEnabled()) log.info("created a pool of " + MAX_NUM + " threads");
if(log.isDebugEnabled()) log.debug("created a pool of " + MAX_NUM + " threads");
    public ThreadPool(int max_num) {        MAX_NUM=max_num;        pool=new ReusableThread[MAX_NUM];        available_threads=new boolean[MAX_NUM];        for(int i=0; i < pool.length; i++) {            pool[i]=null;            available_threads[i]=true;        }            if(log.isInfoEnabled()) log.info("created a pool of " + MAX_NUM + " threads");    }