revert TreeNode extends AtomicReference<ChildData> change (add back AtomicReferenceFieldUpdater for this)
Project: http://git-wip-us.apache.org/repos/asf/curator/repo Commit: http://git-wip-us.apache.org/repos/asf/curator/commit/043270a5 Tree: http://git-wip-us.apache.org/repos/asf/curator/tree/043270a5 Diff: http://git-wip-us.apache.org/repos/asf/curator/diff/043270a5 Branch: refs/heads/master Commit: 043270a58ba861717379dc5963e1febfced09c9a Parents: 939d7dc Author: nickhill <nickh...@us.ibm.com> Authored: Tue Jan 9 15:18:20 2018 +0000 Committer: nickhill <nickh...@us.ibm.com> Committed: Tue Jan 9 15:18:20 2018 +0000 ---------------------------------------------------------------------- .../framework/recipes/cache/TreeCache.java | 37 ++++++++++---------- 1 file changed, 19 insertions(+), 18 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/curator/blob/043270a5/curator-recipes/src/main/java/org/apache/curator/framework/recipes/cache/TreeCache.java ---------------------------------------------------------------------- diff --git a/curator-recipes/src/main/java/org/apache/curator/framework/recipes/cache/TreeCache.java b/curator-recipes/src/main/java/org/apache/curator/framework/recipes/cache/TreeCache.java index a9b8fa8..4dea736 100644 --- a/curator-recipes/src/main/java/org/apache/curator/framework/recipes/cache/TreeCache.java +++ b/curator-recipes/src/main/java/org/apache/curator/framework/recipes/cache/TreeCache.java @@ -202,13 +202,15 @@ public class TreeCache implements Closeable return cd != null && cd != DEAD; } + private static final AtomicReferenceFieldUpdater<TreeNode, ChildData> childDataUpdater = + AtomicReferenceFieldUpdater.newUpdater(TreeNode.class, ChildData.class, "childData"); + private static final AtomicReferenceFieldUpdater<TreeNode, ConcurrentMap<String,TreeNode>> childrenUpdater = (AtomicReferenceFieldUpdater)AtomicReferenceFieldUpdater.newUpdater(TreeNode.class, ConcurrentMap.class, "children"); - private final class TreeNode extends AtomicReference<ChildData> implements Watcher, BackgroundCallback + private final class TreeNode implements Watcher, BackgroundCallback { - private static final long serialVersionUID = 4736888003207088181L; - + volatile ChildData childData; final TreeNode parent; final String path; volatile ConcurrentMap<String, TreeNode> children; @@ -291,11 +293,10 @@ public class TreeCache implements Closeable void wasDeleted() throws Exception { - ChildData oldChildData; - do { - if( (oldChildData = get()) == DEAD ) return; - } while( !compareAndSet(oldChildData, DEAD) ); - + ChildData oldChildData = childDataUpdater.getAndSet(this, DEAD); + if ( oldChildData == DEAD ) { + return; + } ConcurrentMap<String, TreeNode> childMap = childrenUpdater.getAndSet(this,null); if ( childMap != null ) { @@ -374,20 +375,20 @@ public class TreeCache implements Closeable Preconditions.checkState(parent == null, "unexpected EXISTS on non-root node"); if ( event.getResultCode() == KeeperException.Code.OK.intValue() ) { - compareAndSet(DEAD, null); + childDataUpdater.compareAndSet(this, DEAD, null); wasCreated(); } break; case CHILDREN: if ( event.getResultCode() == KeeperException.Code.OK.intValue() ) { - ChildData oldChildData = get(); + ChildData oldChildData = childData; //TODO consider doing update of cversion, pzxid, numChildren only if ( isLive(oldChildData) && oldChildData.getStat().getMzxid() == newStat.getMzxid() ) { // Only update stat if mzxid is same, otherwise we might obscure // GET_DATA event updates. - compareAndSet(oldChildData, new ChildData(oldChildData.getPath(), newStat, oldChildData.getData())); + childDataUpdater.compareAndSet(this, oldChildData, new ChildData(oldChildData.getPath(), newStat, oldChildData.getData())); } if ( event.getChildren().isEmpty() ) @@ -434,15 +435,15 @@ public class TreeCache implements Closeable String eventPath = event.getPath(); ChildData toPublish = new ChildData(eventPath, newStat, event.getData()); ChildData toUpdate = cacheData ? toPublish : new ChildData(eventPath, newStat, null); - for(;;) { - final ChildData oldChildData = get(); + while (true) { + final ChildData oldChildData = childData; if ( (isLive(oldChildData) && newStat.getMzxid() <= oldChildData.getStat().getMzxid()) // Ordinary nodes are not allowed to transition from dead -> live; // make sure this isn't a delayed response that came in after death. || (parent != null && oldChildData == DEAD) ) { break; } - if ( compareAndSet(oldChildData, toUpdate) ) + if ( childDataUpdater.compareAndSet(this, oldChildData, toUpdate) ) { if ( !isLive(oldChildData) ) { @@ -669,7 +670,7 @@ public class TreeCache implements Closeable public Map<String, ChildData> getCurrentChildren(String fullPath) { TreeNode node = find(fullPath); - if ( node == null || !isLive(node.get()) ) + if ( node == null || !isLive(node.childData) ) { return null; } @@ -685,7 +686,7 @@ public class TreeCache implements Closeable for ( Map.Entry<String, TreeNode> entry : map.entrySet() ) { TreeNode childNode = entry.getValue(); - ChildData childData = childNode.get(); + ChildData childData = childNode.childData; if ( isLive(childData) ) { builder.put(entry.getKey(), childData); @@ -695,7 +696,7 @@ public class TreeCache implements Closeable } // Double-check liveness after retreiving children. - return isLive(node.get()) ? result : null; + return isLive(node.childData) ? result : null; } /** @@ -713,7 +714,7 @@ public class TreeCache implements Closeable { return null; } - ChildData result = node.get(); + ChildData result = node.childData; return result != DEAD ? result : null; }
