aboutsummaryrefslogtreecommitdiffstats
path: root/infrastructure/net.appjet.oui/synchronizer.scala
diff options
context:
space:
mode:
Diffstat (limited to 'infrastructure/net.appjet.oui/synchronizer.scala')
-rw-r--r--infrastructure/net.appjet.oui/synchronizer.scala69
1 files changed, 69 insertions, 0 deletions
diff --git a/infrastructure/net.appjet.oui/synchronizer.scala b/infrastructure/net.appjet.oui/synchronizer.scala
new file mode 100644
index 0000000..2a6d9c1
--- /dev/null
+++ b/infrastructure/net.appjet.oui/synchronizer.scala
@@ -0,0 +1,69 @@
+/**
+ * Copyright 2009 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.appjet.oui;
+
+class Synchronizer {
+ import java.util.concurrent.locks.ReentrantLock;
+ import java.util.concurrent.ConcurrentHashMap;
+
+ private val lockMap = new ConcurrentHashMap[Object, Lock];
+ private val monitor = new Object {};
+
+ private class Lock {
+ var users = 0;
+ val impl = new ReentrantLock;
+ }
+
+ def acquire(key: Object) {
+ val lock = monitor.synchronized {
+ var lck = lockMap.get(key);
+ if (lck == null) {
+ lck = new Lock;
+ lockMap.put(key, lck);
+ }
+ lck.users += 1;
+ lck;
+ }
+ lock.impl.lock();
+ }
+
+ def isHeld(key: Object): Boolean = {
+ monitor.synchronized {
+ val lck = lockMap.get(key);
+ if (lck == null) {
+ false;
+ }
+ else {
+ lck.impl.isLocked;
+ }
+ }
+ }
+
+ def release(key: Object) {
+ val lock = monitor.synchronized {
+ var lck = lockMap.get(key);
+ lck.users -= 1;
+ if (lck.users == 0) {
+ lockMap.remove(key);
+ }
+ lck;
+ }
+ lock.impl.unlock();
+ }
+}
+
+object GlobalSynchronizer extends Synchronizer;