About several common queues in the Java Collection Class library

Several common queues in Java

The difference between a blocking queue and a normal queue is that when the queue is empty, the operation to get elements from the queue is blocked, or when the queue is full, the operation to add elements to the queue is blocked. Threads that attempt to fetch elements from an empty blocking queue are blocked until other threads insert new elements into the empty queue. Similarly, threads that attempt to add new elements to the full blocking queue are also blocked until other threads make the queue idle again, such as removing one or more elements from the queue, or completely emptying the queue.

First type: Concurrentlinkedqueue, high performance nonblocking unbounded queue

Code Demo:

1concurrentlinkedqueue<string> q =NewConcurrentlinkedqueue<string>();2Q.offer ("a");3Q.offer ("B");4Q.offer ("C");5Q.offer ("D");6Q.add ("E");7         8System.out.println (Q.poll ());//a remove elements from the head and delete them from the queue9System.out.println (Q.size ());//4TenSystem.out.println (Q.peek ());//b OneSystem.out.println (Q.size ());//4

Second type: Arrayblockingqueue, array-based blocking queue, bounded queue

1  New Arrayblockingqueue<string> (5); 2         Array.put ("a"); 3         Array.put ("B"); 4         Array.add ("C"); 5         Array.add ("D"); 6         Array.add ("E"); 7         // Array.add ("F"); 8         System.out.println (Array.offer ("A", 3, Timeunit.seconds)); 　　　　

Third type: linkedblockingqueue, blocking queue, no queue

1linkedblockingqueue<string> q =NewLinkedblockingqueue<string>();2Q.offer ("a");3Q.offer ("B");4Q.offer ("C");5Q.offer ("D");6Q.offer ("E");7Q.add ("F");8         //System.out.println (Q.size ());9         Ten //For (Iterator Iterator = Q.iterator (); Iterator.hasnext ();) { One //String string = (string) iterator.next (); A //System.out.println (string); - //        } -          thelist<string> list =NewArraylist<string>(); -System.out.println (Q.drainto (list, 3)); - System.out.println (List.size ()); -          for(String string:list) { + System.out.println (string); -}

Fourth type: Synchronousqueue

1 Finalsynchronousqueue<string> q =NewSynchronousqueue<string>();2Thread T1 =NewThread (NewRunnable () {3 @Override4              Public voidrun () {5                 Try {6 System.out.println (Q.take ());7}Catch(interruptedexception e) {8 e.printstacktrace ();9                 }Ten             } One         }); A T1.start (); -Thread t2 =NewThread (NewRunnable () { -              the @Override -              Public voidrun () { -Q.add ("ASDASD"); -             } +         }); -T2.start ();

About several common queues in the Java Collection Class library