added lock util class

akka-core/src/main/scala/util/LockUtil.scala

@@ -0,0 +1,51 @@
+/**
+ * Copyright (C) 2009-2010 Scalable Solutions AB <http://scalablesolutions.se>
+ */
+
+package se.scalablesolutions.akka.util
+
+import java.util.concurrent.locks.{ReentrantReadWriteLock, ReentrantLock}
+
+/**
+ * @author <a href="http://jonasboner.com">Jonas Bon&#233;r</a>
+ */
+class ReentrantGuard {
+  private val lock = new ReentrantLock
+
+  def withGuard[T](body: => T): T = {
+    lock.lock
+    try {
+      body
+    } finally {
+      lock.unlock
+    }
+  }
+}
+
+/**
+ * @author <a href="http://jonasboner.com">Jonas Bon&#233;r</a>
+ */
+class ReadWriteGuard {
+  private val rwl = new ReentrantReadWriteLock
+  private val readLock = rwl.readLock
+  private val writeLock = rwl.writeLock
+
+  def withWriteGuard[T](body: => T): T = {
+    writeLock.lock
+    try {
+      body
+    } finally {
+      writeLock.unlock
+    }
+  }
+
+  def withReadGuard[T](body: => T): T = {
+    readLock.lock
+    try {
+      body
+    } finally {
+      readLock.unlock
+    }
+  }
+}
+