diff --git a/src/main/java/li/strolch/persistence/api/TransactionCloseStrategy.java b/src/main/java/li/strolch/persistence/api/TransactionCloseStrategy.java
index 40604eea2..18f25e5d8 100644
--- a/src/main/java/li/strolch/persistence/api/TransactionCloseStrategy.java
+++ b/src/main/java/li/strolch/persistence/api/TransactionCloseStrategy.java
@@ -33,7 +33,5 @@ public enum TransactionCloseStrategy {
 	/**
 	 * @param tx
 	 */
-	public void close(StrolchTransaction tx) {
-		throw new UnsupportedOperationException("Override in enum!"); //$NON-NLS-1$
-	}
+	public abstract void close(StrolchTransaction tx);
 }
\ No newline at end of file