added missing file.

1 files changed, 28 insertions, 0 deletions

diff --git a/src/compiler/scala/tools/nsc/util/InterruptReq.scala b/src/compiler/scala/tools/nsc/util/InterruptReq.scala
new file mode 100644
index 0000000000..aa7804acbe
--- /dev/null
+++ b/src/compiler/scala/tools/nsc/util/InterruptReq.scala
@@ -0,0 +1,28 @@
+package scala.tools.nsc
+package util
+
+/** A class of work items to be used in interrupt requests.
+ */
+abstract class InterruptReq {
+  /** The result type of the operation
+   */
+  type R
+
+  /** The operation to be performed */
+  protected val todo: () => R
+
+  /** The result provided */
+  private var result: Option[R] = None
+
+  /** To be called from interrupted server to execute demanded task */
+  def execute(): Unit = synchronized {
+    result = Some(todo())
+    notify()
+  }
+
+  /** To be called from interrupting client to get result fo interrupt */
+  def getResult(): R = synchronized {
+    while (result.isEmpty) wait()
+    result.get
+  }
+}