Java Code Examples for java.util.concurrent.LinkedBlockingDeque#poll()

The following examples show how to use java.util.concurrent.LinkedBlockingDeque#poll() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source File: ChatController.java    From SpringMVC-Project with MIT License 6 votes vote down vote up 
@Override
public void run() {
    LinkedBlockingDeque<MessageVo> messageQueue = MESSAGE_QUEUE_MAP.get(userId);
    BaseResponse<List<MessageVo>> response = new BaseResponse<>();
    List<MessageVo> list = Lists.newArrayList();

    MessageVo vo;
    try {
        if ((vo = messageQueue.poll(timeout, TimeUnit.MILLISECONDS)) != null) {
            list.add(vo);
            //一次最多取10条信息
            for (int i = 0; i < 9; i++) {
                vo = messageQueue.poll();
                if (vo == null) {
                    break;
                }
                list.add(vo);
            }
        }
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

    response.setData(list);
    deferredResult.setResult(response);
}
Example 2
Source File: LinkedBlockingDequeTest.java    From openjdk-jdk9 with GNU General Public License v2.0 6 votes vote down vote up 
/**
 * drainTo(c, n) empties first min(n, size) elements of queue into c
 */
public void testDrainToN() {
    LinkedBlockingDeque q = new LinkedBlockingDeque();
    for (int i = 0; i < SIZE + 2; ++i) {
        for (int j = 0; j < SIZE; j++)
            assertTrue(q.offer(new Integer(j)));
        ArrayList l = new ArrayList();
        q.drainTo(l, i);
        int k = (i < SIZE) ? i : SIZE;
        assertEquals(k, l.size());
        assertEquals(SIZE - k, q.size());
        for (int j = 0; j < k; ++j)
            assertEquals(l.get(j), new Integer(j));
        do {} while (q.poll() != null);
    }
}
Example 3
Source File: LinkedBlockingDequeTest.java    From j2objc with Apache License 2.0 6 votes vote down vote up 
/**
 * drainTo(c, n) empties first min(n, size) elements of queue into c
 */
public void testDrainToN() {
    LinkedBlockingDeque q = new LinkedBlockingDeque();
    for (int i = 0; i < SIZE + 2; ++i) {
        for (int j = 0; j < SIZE; j++)
            assertTrue(q.offer(new Integer(j)));
        ArrayList l = new ArrayList();
        q.drainTo(l, i);
        int k = (i < SIZE) ? i : SIZE;
        assertEquals(k, l.size());
        assertEquals(SIZE - k, q.size());
        for (int j = 0; j < k; ++j)
            assertEquals(l.get(j), new Integer(j));
        do {} while (q.poll() != null);
    }
}
Example 4
Source File: LocalJobHistoryStore.java    From airpal with Apache License 2.0 6 votes vote down vote up 
@Override
protected boolean evictItem(LinkedBlockingDeque<Job> deque) {
    final Job job = deque.poll();

    if (job != null) {
        if (job.getState().isDone()) {
            return true;
        } else {
            boolean addResult = add(job);
            boolean secondEviction = evictItem(deque);

            return addResult && secondEviction;
        }
    } else {
        return false;
    }
}
Example 5
Source File: LinkedBlockingDequeTest.java    From openjdk-jdk9 with GNU General Public License v2.0 5 votes vote down vote up 
/**
 * element returns next element, or throws NSEE if empty
 */
public void testElement() {
    LinkedBlockingDeque q = populatedDeque(SIZE);
    for (int i = 0; i < SIZE; ++i) {
        assertEquals(i, q.element());
        q.poll();
    }
    try {
        q.element();
        shouldThrow();
    } catch (NoSuchElementException success) {}
}
Example 6
Source File: LinkedBlockingDequeTest.java    From openjdk-jdk9 with GNU General Public License v2.0 5 votes vote down vote up 
/**
 * contains(x) reports true when elements added but not yet removed
 */
public void testContains() {
    LinkedBlockingDeque q = populatedDeque(SIZE);
    for (int i = 0; i < SIZE; ++i) {
        assertTrue(q.contains(new Integer(i)));
        q.poll();
        assertFalse(q.contains(new Integer(i)));
    }
}
Example 7
Source File: LinkedBlockingDequeTest.java    From j2objc with Apache License 2.0 5 votes vote down vote up 
/**
 * element returns next element, or throws NSEE if empty
 */
public void testElement() {
    LinkedBlockingDeque q = populatedDeque(SIZE);
    for (int i = 0; i < SIZE; ++i) {
        assertEquals(i, q.element());
        q.poll();
    }
    try {
        q.element();
        shouldThrow();
    } catch (NoSuchElementException success) {}
}
Example 8
Source File: LinkedBlockingDequeTest.java    From j2objc with Apache License 2.0 5 votes vote down vote up 
/**
 * contains(x) reports true when elements added but not yet removed
 */
public void testContains() {
    LinkedBlockingDeque q = populatedDeque(SIZE);
    for (int i = 0; i < SIZE; ++i) {
        assertTrue(q.contains(new Integer(i)));
        q.poll();
        assertFalse(q.contains(new Integer(i)));
    }
}
Example 9
Source File: RegressionTree.java    From pyramid with Apache License 2.0 5 votes vote down vote up 
public List<Integer> getFeatureIndices(){
    List<Integer> featureIndices = new ArrayList<Integer>();
    LinkedBlockingDeque<Node> queue = new LinkedBlockingDeque<Node>();
    queue.offer(this.root);
    while(queue.size()!=0){
        Node node = queue.poll();
        if (! node.isLeaf()){
            //don't add the feature for leaf node, as it is useless
            featureIndices.add(node.getFeatureIndex());
            queue.offer(node.getLeftChild());
            queue.offer(node.getRightChild());
        }
    }
    return featureIndices;
}
Example 10
Source File: TimeCacheQueue.java    From jstorm with Apache License 2.0 5 votes vote down vote up 
public K poll() {
    synchronized (_lock) {
        Iterator<LinkedBlockingDeque<K>> itr = _buckets.descendingIterator();
        while (itr.hasNext()) {
            LinkedBlockingDeque<K> bucket = itr.next();
            K entry = bucket.poll();
            if (entry != null) {
                return entry;
            }
        }

        return null;
    }
}
Example 11
Source File: LMDBDataWriter.java    From twister2 with Apache License 2.0 4 votes vote down vote up 
@Override
  public void run() {

    Txn<ByteBuffer> writeTxn = null;
    Map<Integer, Cursor<ByteBuffer>> openCoursors = new HashMap<>();
    List<Integer> opIDs = new ArrayList<>();
    int opID = 0;
    Cursor<ByteBuffer> c = null;
    int count = 0;
    while (currentDbiCount == 0) {
      if (dbMapRef.size() > 0 && dataQueueMapRef.size() > 0) {
        writeTxn = this.envRef.txnWrite();
        for (Map.Entry<Integer, Dbi<ByteBuffer>> dbiEntry : dbMapRef.entrySet()) {
          opID = dbiEntry.getKey();
          c = dbiEntry.getValue().openCursor(writeTxn);
          currentDbiCount++;
        }
      }
    }

    Pair<byte[], byte[]> tempPair = null;
    LinkedBlockingDeque<Pair<byte[], byte[]>> dataQueue = dataQueueMapRef.get(opID);

    while (true) {

//      if (dbMapRef.size() > currentDbiCount) {
//        for (Map.Entry<Integer, Dbi<ByteBuffer>> dbiEntry : dbMapRef.entrySet()) {
//          if (!openCoursors.containsKey(dbiEntry.getKey())) {
//            openCoursors.put(dbiEntry.getKey(), dbiEntry.getValue().openCursor(writeTxn));
//            opIDs.add(dbiEntry.getKey());
//            currentDbiCount++;
//          }
//        }
//      }
//
//      if(currentDbiCount == 0){
//        Thread.yield();
//      }
      tempPair = dataQueue.poll();
      if (tempPair != null) {
        setupThreadLocalBuffers(tempPair.getKey().length, tempPair.getValue().length);
        keyBuffer.put(tempPair.getKey());
        keyBuffer.flip();

        dataBuffer.putInt(tempPair.getValue().length);
        dataBuffer.put(tempPair.getValue());
        dataBuffer.flip();

        c.put(keyBuffer, dataBuffer);
        LMDBMemoryManager.needsCommitWriter = true;
        count++;
        if (count % 2000000 == 0 && count > 0) {
          writeTxn.commit();
          writeTxn.close();
          writeTxn = this.envRef.txnWrite();
          c = dbMapRef.get(opID).openCursor(writeTxn);
          LMDBMemoryManager.needsCommitWriter = false;
          LMDBMemoryManager.needsCommitReader = false;
          System.out.println("added 2  mil to mm");
        }
      }

      if (LMDBMemoryManager.needsCommitReader) {
        writeTxn.commit();
        writeTxn.close();
        writeTxn = this.envRef.txnWrite();
        c = dbMapRef.get(opID).openCursor(writeTxn);
        LMDBMemoryManager.needsCommitWriter = false;
        LMDBMemoryManager.needsCommitReader = false;
      }

    }


  }