Simplify getting the first element in a queue if present (c0926998) · Commits · e / os / android_frameworks_base

core/java/android/os/CombinedMessageQueue/MessageQueue.java

+15 −37

Original line number	Diff line number	Diff line
		@@ -296,23 +296,13 @@ public final class MessageQueue {
		return false;
		}

		MessageNode msgNode = null;
		MessageNode asyncMsgNode = null;

		if (!mPriorityQueue.isEmpty()) {
		try {
		msgNode = mPriorityQueue.first();
		} catch (NoSuchElementException e) { }
		}

		if (!mAsyncPriorityQueue.isEmpty()) {
		try {
		asyncMsgNode = mAsyncPriorityQueue.first();
		} catch (NoSuchElementException e) { }
		final MessageNode msgNode = first(mPriorityQueue);
		if (msgNode != null && msgNode.getWhen() <= now) {
		return false;
		}

		if ((msgNode != null && msgNode.getWhen() <= now)
		\|\| (asyncMsgNode != null && asyncMsgNode.getWhen() <= now)) {
		final MessageNode asyncMsgNode = first(mAsyncPriorityQueue);
		if (asyncMsgNode != null && asyncMsgNode.getWhen() <= now) {
		return false;
		}

		@@ -730,10 +720,8 @@ public final class MessageQueue {
		*/

		/* Get the first node from each queue */
		Iterator<MessageNode> queueIter = mPriorityQueue.iterator();
		MessageNode msgNode = iterateNext(queueIter);
		Iterator<MessageNode> asyncQueueIter = mAsyncPriorityQueue.iterator();
		MessageNode asyncMsgNode = iterateNext(asyncQueueIter);
		MessageNode msgNode = first(mPriorityQueue);
		MessageNode asyncMsgNode = first(mAsyncPriorityQueue);

		if (DEBUG) {
		if (msgNode != null) {
		@@ -1260,16 +1248,10 @@ public final class MessageQueue {

		private void removeSyncBarrierConcurrent(int token) {
		boolean removed;
		MessageNode first;
		final MatchBarrierToken matchBarrierToken = new MatchBarrierToken(token);

		try {
		/* Retain the first element to see if we are currently stuck on a barrier. */
		first = mPriorityQueue.first();
		} catch (NoSuchElementException e) {
		/* The queue is empty */
		first = null;
		}
		// Retain the first element to see if we are currently stuck on a barrier.
		final MessageNode first = first(mPriorityQueue);

		removed = findOrRemoveMessages(null, 0, null, null, 0, matchBarrierToken, true);
		if (removed && first != null) {
		@@ -1535,8 +1517,7 @@ public final class MessageQueue {
		// Call nextMessage to get the stack drained into our priority queues
		nextMessage(true, false);

		Iterator<MessageNode> queueIter = mPriorityQueue.iterator();
		MessageNode queueNode = iterateNext(queueIter);
		MessageNode queueNode = first(mPriorityQueue);

		return (queueNode != null && queueNode.isBarrier());
		} else {
		@@ -2447,16 +2428,13 @@ public final class MessageQueue {
		return nodeA != null ? nodeA : nodeB;
		}

		private MessageNode iterateNext(Iterator<MessageNode> iter) {
		if (iter.hasNext()) {
		private static MessageNode first(ConcurrentSkipListSet<MessageNode> queue) {
		try {
		return iter.next();
		return queue.first();
		} catch (NoSuchElementException e) {
		/* The queue is empty - this can happen if we race with remove */
		}
		}
		return null;
		}
		}

		/* Move any non-cancelled messages into the priority queue */
		private void drainStack(StackNode oldTop) {