java - how to use BlockingQueues -

i having problem blockingqueues. size of queue comes 1 first loop , 0 after there there. variables 'as' null.

public class board extends jpanel {     private myclass mc;     private thread combatthread;     final blockingqueue<myclass> queue = new linkedblockingqueue<myclass>();      public board() {         mc = new myclass();         mc.add(1);         mc.add(2);         combatthread = new thread(new cthread(queue));          test();     }      public void test() {             try {             queue.add(mc);         } catch(exception e1) {}         combatthread.start();     }       public class cthread implements runnable {         private myclass as;          public cthread(blockingqueue queue) {          }          public void run() {             while( true ){                 try {                     = queue.poll(); //as null                 } catch (exception e) {}             }         }     } } 

in constructor

public board() 

you create 1 object - mc, , give 2 values (1,2)

in method

public void test() 

you add 1 object queue

queue.add(mc); 

so when thread starts, queue contains 1 (myclass)mc instance reference, , mc object should contain 1 , 2 values (i not sure because not give myclass source). first iteration in

  while( true ){                 try {                     = queue.poll(); //as null                 } catch (exception e) {}             } 

will assign "as" variable reference "mc". how know object kind of queue, why think asarray method should work? implement or inherit somewhere? suggest not. if ask blockingqueue mess.

myclass - here wrong. class name should start capital letter. read java name conventions.

this constructor confuse too, nothing, why use it?

 public cthread(blockingqueue queue) {          } 

i think should read http://javarevisited.blogspot.com/2012/02/producer-consumer-design-pattern-with.html, see how blockingqueue works, see not understand basics, may should start beginners books variable references, inheritance, collections , after return task.