--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/dancres/blitz/txn/TxnOp.java	Sat Mar 21 11:00:06 2009 +0000
@@ -0,0 +1,22 @@
+package org.dancres.blitz.txn;
+
+import java.io.Serializable;
+import java.io.IOException;
+
+import org.dancres.blitz.entry.OpInfo;
+
+/**
+   <p>
+   Each separate operation of a Transaction identified by TxnId is a TxnOp
+   which should implement this interface.  TxnOp's are repeatable, disk-level
+   actions which can be logged to disk and re-applied during system recovery.
+   </p>
+ */
+public interface TxnOp extends Serializable {
+    /**
+       Must be invoked inside an active DiskTxn.
+     */
+    public void restore(TxnState aState) throws IOException;
+    public void commit(TxnState aState) throws IOException;
+    public void abort(TxnState aState) throws IOException;
+}