docs(backPressure): add comments for DCL.

PhantomThief · Oct 13, 2020 · 5923c9f · 5923c9f
1 parent dd54b63
commit 5923c9f
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/main/java/com/github/phantomthief/collection/impl/SimpleBufferTrigger.java b/src/main/java/com/github/phantomthief/collection/impl/SimpleBufferTrigger.java
@@ -142,7 +142,8 @@ public void enqueue(E element) {
             boolean pass = false;
             if (rejectHandler != null) {
                 if (writeLock != null && writeCondition != null) {
-                    writeLock.lock();
+                    writeLock.lock(); // 这里采用 DCL，是为了避免部分消费情况下没有 signalAll 唤醒，导致的卡死问题
+                    // 判断堵塞的条件也的确应该在锁块内保护，之前的代码在临界区（counter）的保护上是有缺陷的
                 }
                 try {
                     currentCount = counter.get();