Merge pull request #342 from yahoo/bratseth/transactional-application-remove

Bratseth/transactional application remove

4 files changed, 59 insertions, 30 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/transaction/AbstractTransaction.java b/vespajlib/src/main/java/com/yahoo/transaction/AbstractTransaction.java
new file mode 100644
index 00000000000..cff02f4da53
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/transaction/AbstractTransaction.java
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.transaction;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Logger;
+
+/**
+ * A convenience base transaction class for multi-operation transactions
+ * which maintains the ordered list of operations to commit and provides a default
+ * implementation of rollbackOrLog which logs a SEVERE message.
+ * 
+ * @author bratseth
+ */
+public abstract class AbstractTransaction implements Transaction {
+
+    private static final Logger log = Logger.getLogger(AbstractTransaction.class.getName());
+    private final List<Operation> operations = new ArrayList<>();
+
+    protected AbstractTransaction() { }
+
+    @Override
+    public Transaction add(Operation operation) {
+        this.operations.add(operation);
+        return this;
+    }
+
+    @Override
+    public Transaction add(List<Operation> operations) {
+        this.operations.addAll(operations);
+        return this;
+    }
+
+    @Override
+    public List<Operation> operations() { return operations; }
+
+    /** Default implementations which logs a severe message. Operations should implement toString to use this. */
+    @Override
+    public void rollbackOrLog() {
+        log.severe("The following operations were incorrectly committed and probably require " +
+                   "manual correction: " + operations());
+    }
+
+    /** Default implementation which only clears operations */
+    @Override
+    public void close() {
+        operations.clear();
+    }
+
+}
diff --git a/vespajlib/src/main/java/com/yahoo/transaction/NestedTransaction.java b/vespajlib/src/main/java/com/yahoo/transaction/NestedTransaction.java
index 4be0a32ffe8..f437aa8ac19 100644
--- a/vespajlib/src/main/java/com/yahoo/transaction/NestedTransaction.java
+++ b/vespajlib/src/main/java/com/yahoo/transaction/NestedTransaction.java
@@ -21,9 +21,6 @@ public final class NestedTransaction implements AutoCloseable {
     /** Nested transactions with ordering constraints, in the order they are added */
     private final List<ConstrainedTransaction> transactions = new ArrayList<>(2);
 
-    /** Transaction ordering pairs */
-    //private final List<OrderingConstraint> transactionOrders = new ArrayList<>(2);
-
     /** A list of (non-transactional) operations to execute after this transaction has committed successfully */
     private final List<Runnable> onCommitted = new ArrayList<>(2);
 
diff --git a/vespajlib/src/main/java/com/yahoo/transaction/Transaction.java b/vespajlib/src/main/java/com/yahoo/transaction/Transaction.java
index 642438dda0a..bde458cb150 100644
--- a/vespajlib/src/main/java/com/yahoo/transaction/Transaction.java
+++ b/vespajlib/src/main/java/com/yahoo/transaction/Transaction.java
@@ -4,8 +4,11 @@ package com.yahoo.transaction;
 import java.util.List;
 
 /**
- * An interface for building a transaction and committing it. Implementations are required to atomically apply changes
+ * A transaction against a single system, which may include several operations against the system, 
+ * to be committed as one.
+ * Implementations are required to atomically apply changes
  * in the commit step or throw an exception if it fails.
+ * Operations are performed in the order they are added.
  *
  * @author lulf
  * @author bratseth
@@ -65,8 +68,9 @@ public interface Transaction extends AutoCloseable {
 
     /**
      * Operations that a transaction supports should implement this interface.
+     * It does not define any methods because the interface to use is a contract between the
+     * specific transaction and operation type used.
      */
-    public interface Operation {
-    }
+    interface Operation { }
 
 }
diff --git a/vespajlib/src/test/java/com/yahoo/transaction/NestedTransactionTestCase.java b/vespajlib/src/test/java/com/yahoo/transaction/NestedTransactionTestCase.java
index d75daa506b4..887c3909f73 100644
--- a/vespajlib/src/test/java/com/yahoo/transaction/NestedTransactionTestCase.java
+++ b/vespajlib/src/test/java/com/yahoo/transaction/NestedTransactionTestCase.java
@@ -111,30 +111,12 @@ public class NestedTransactionTestCase {
         }
     }
 
-    private static class MockTransaction implements Transaction {
+    private static class MockTransaction extends AbstractTransaction {
 
         public boolean prepared = false, committed = false, rolledback = false;
-        private List<Operation> operations = new ArrayList<>();
 
         public MockTransaction(String name) {
-            operations.add(new MockOperation(name));
-        }
-
-        @Override
-        public Transaction add(Operation operation) {
-            operations.add(operation);
-            return this;
-        }
-
-        @Override
-        public Transaction add(List<Operation> operation) {
-            operations.addAll(operation);
-            return this;
-        }
-
-        @Override
-        public List<Operation> operations() {
-            return operations;
+            add(new MockOperation(name));
         }
 
         @Override
@@ -156,10 +138,6 @@ public class NestedTransactionTestCase {
             rolledback = true;
         }
 
-        @Override
-        public void close() {
-        }
-
     }
 
     private static class MockOperation implements Transaction.Operation {