Merge pull request #1520 from h2database/pit-if-absent

Fixes bug in PutIfAbsentDecisionMaker

h2/src/main/org/h2/mvstore/tx/Transaction.java

@@ -395,6 +395,7 @@ public class Transaction {
         try {
             store.rollbackTo(this, logId, savepointId);
         } finally {
+            notifyAllWaitingTransactions();
             long expectedState = composeState(STATUS_ROLLING_BACK, logId, hasRollback(lastState));
             long newState = composeState(STATUS_OPEN, savepointId, true);
             if (!statusAndLogId.compareAndSet(expectedState, newState)) {
@@ -404,7 +405,6 @@ public class Transaction {
                                 "while rollback to savepoint was in progress",
                         transactionId);
             }
-            notifyAllWaitingTransactions();
         }
     }
 
@@ -412,14 +412,26 @@ public class Transaction {
      * Roll the transaction back. Afterwards, this transaction is closed.
      */
     public void rollback() {
+        Throwable ex = null;
         try {
             long lastState = setStatus(STATUS_ROLLED_BACK);
             long logId = getLogId(lastState);
             if (logId > 0) {
                 store.rollbackTo(this, logId, 0);
             }
+        } catch (Throwable e) {
+            ex = e;
+            throw e;
         } finally {
-            store.endTransaction(this, true);
+            try {
+                store.endTransaction(this, true);
+            } catch (Throwable e) {
+                if (ex == null) {
+                    throw e;
+                } else {
+                    ex.addSuppressed(e);
+                }
+            }
         }
     }
 

h2/src/main/org/h2/mvstore/tx/TxDecisionMaker.java

@@ -168,9 +168,12 @@ abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
                     }
                     logIt(existingValue);
                     return setDecision(MVMap.Decision.PUT);
-                } else if (isCommitted(blockingId) && existingValue.value == null) {
+                } else if (isCommitted(blockingId)) {
                     // entry belongs to a committing transaction
                     // and therefore will be committed soon
+                    if(existingValue.value != null) {
+                        return setDecision(MVMap.Decision.ABORT);
+                    }
                     logIt(null);
                     return setDecision(MVMap.Decision.PUT);
                 } else if (getBlockingTransaction() != null) {