From 0b55ddeedf221b3f85e45574dd51d9425fce8d3f Mon Sep 17 00:00:00 2001
From: Simon Willnauer <simonw@apache.org>
Date: Mon, 12 Sep 2011 19:18:05 +0000
Subject: [PATCH] LUCENE-3428: force DWPT unlock if unchecked exception is
 thrown by DWFC#addFlushableState

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1169877 13f79535-47bb-0310-9956-ffa450edef68
---
 .../index/DocumentsWriterFlushControl.java    | 24 ++++++++++++-------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/lucene/src/java/org/apache/lucene/index/DocumentsWriterFlushControl.java b/lucene/src/java/org/apache/lucene/index/DocumentsWriterFlushControl.java
index 35a372cd95f..cdef910f570 100644
--- a/lucene/src/java/org/apache/lucene/index/DocumentsWriterFlushControl.java
+++ b/lucene/src/java/org/apache/lucene/index/DocumentsWriterFlushControl.java
@@ -366,15 +366,23 @@ public final class DocumentsWriterFlushControl {
   ThreadState obtainAndLock() {
     final ThreadState perThread = perThreadPool.getAndLock(Thread
         .currentThread(), documentsWriter);
-    if (perThread.isActive()
-        && perThread.perThread.deleteQueue != documentsWriter.deleteQueue) {
-      // There is a flush-all in process and this DWPT is
-      // now stale -- enroll it for flush and try for
-      // another DWPT:
-      addFlushableState(perThread);
+    boolean success = false;
+    try {
+      if (perThread.isActive()
+          && perThread.perThread.deleteQueue != documentsWriter.deleteQueue) {
+        // There is a flush-all in process and this DWPT is
+        // now stale -- enroll it for flush and try for
+        // another DWPT:
+        addFlushableState(perThread);
+      }
+      success = true;
+      // simply return the ThreadState even in a flush all case sine we already hold the lock
+      return perThread;
+    } finally {
+      if (!success) { // make sure we unlock if this fails
+        perThread.unlock();
+      }
     }
-    // simply return the ThreadState even in a flush all case sine we already hold the lock
-    return perThread;
   }
   
   void markForFullFlush() {