Uses term 'close' instead of mixed apply/close and makes TxStateVisit…

…or an AutoCloseable since less confusing than having explicit done() method

community/kernel/src/main/java/org/neo4j/kernel/api/txstate/TxStateVisitor.java

@@ -36,7 +36,7 @@
 /**
  * A visitor for visiting the changes that have been made in a transaction.
  */
-public interface TxStateVisitor
+public interface TxStateVisitor extends AutoCloseable
 {
     void visitCreatedNode( long id );
 
@@ -94,10 +94,8 @@ void visitAddedRelationshipPropertyExistenceConstraint( RelationshipPropertyExis
 
     void visitDroppedProcedure( ProcedureDescriptor procedureDescriptor );
 
-    /**
-     * Must be called Called after all visitor methods, i.e. all changes have been visited.
-     */
-    void done();
+    @Override
+    void close();
 
     class Adapter implements TxStateVisitor
     {
@@ -233,7 +231,7 @@ public void visitDroppedProcedure( ProcedureDescriptor procedureDescriptor )
         }
 
         @Override
-        public void done()
+        public void close()
         {
         }
     }
@@ -406,9 +404,9 @@ public void visitDroppedProcedure( ProcedureDescriptor procedureDescriptor )
         }
 
         @Override
-        public void done()
+        public void close()
         {
-            actual.done();
+            actual.close();
         }
     }
 }

community/kernel/src/main/java/org/neo4j/kernel/impl/api/TransactionRepresentationCommitProcess.java

@@ -148,7 +148,7 @@ private void close( TransactionToApply batch )
         {
             if ( batch.commitment().markedAsCommitted() )
             {
-                batch.commitment().publishAsApplied();
+                batch.commitment().publishAsClosed();
             }
             batch = batch.next();
         }

community/kernel/src/main/java/org/neo4j/kernel/impl/storageengine/StorageEngine.java

@@ -104,7 +104,7 @@ Collection<Command> createCommands(
     /**
      * Apply a batch of transactions to this storage. Transactions are applied to storage after being committed,
      * i.e. appended to a log by {@link TransactionAppender}. Implementations should NOT
-     * {@link Commitment#publishAsApplied() mark transactions as applied}, instead caller is expected to do that.
+     * {@link Commitment#publishAsClosed() mark transactions as applied}, instead caller is expected to do that.
      * Caller is typically {@link TransactionCommitProcess}.
      *
      * @param batch batch of transactions to apply to storage.

community/kernel/src/main/java/org/neo4j/kernel/impl/storageengine/impl/recordstorage/RecordStorageEngine.java

@@ -230,6 +230,7 @@ public StoreReadLayer storeReadLayer()
         return storeLayer;
     }
 
+    @SuppressWarnings( "resource" )
     @Override
     public Collection<Command> createCommands(
             TransactionState txState,
@@ -267,8 +268,10 @@ public Collection<Command> createCommands(
                 txStateVisitor );
         txStateVisitor = new TransactionCountingStateVisitor(
                 txStateVisitor, storeLayer, txState, countsRecordState );
-        txState.accept( txStateVisitor );
-        txStateVisitor.done();
+        try ( TxStateVisitor visitor = txStateVisitor )
+        {
+            txState.accept( txStateVisitor );
+        }
 
         // Convert record state into commands
         recordState.extractCommands( commands );

community/kernel/src/main/java/org/neo4j/kernel/impl/storageengine/impl/recordstorage/TransactionToRecordStateVisitor.java

@@ -72,7 +72,7 @@ public TransactionToRecordStateVisitor( TransactionRecordState recordState, Runn
     }
 
     @Override
-    public void done()
+    public void close()
     {
         try
         {

community/kernel/src/main/java/org/neo4j/kernel/impl/transaction/log/Commitment.java

@@ -19,14 +19,15 @@
  */
 package org.neo4j.kernel.impl.transaction.log;
 
+import org.neo4j.kernel.impl.api.TransactionCommitProcess;
+import org.neo4j.kernel.impl.api.TransactionToApply;
+import org.neo4j.kernel.impl.transaction.tracing.LogAppendEvent;
 
 /**
- * A way to mark a transaction as committed after
- * {@link TransactionAppender#append(org.neo4j.kernel.impl.transaction.TransactionRepresentation, long) appended}
- * and manually {@link TransactionAppender#force() forced} and later closed after
- * {@link org.neo4j.kernel.impl.api.TransactionRepresentationStoreApplier#apply(
- * org.neo4j.kernel.impl.transaction.TransactionRepresentation, org.neo4j.kernel.impl.api.index.ValidatedIndexUpdates,
- *  org.neo4j.kernel.impl.locking.LockGroup, long, org.neo4j.kernel.impl.api.TransactionApplicationMode)} .
+ * Represents a commitment that invoking {@link TransactionAppender#append(TransactionToApply, LogAppendEvent)}
+ * means. As a transaction is carried through the {@link TransactionCommitProcess} this commitment is updated
+ * when {@link #publishAsCommitted() committed} (which happens when appending to log), but also
+ * when {@link #publishAsClosed() closing}.
  */
 public interface Commitment
 {
@@ -38,7 +39,7 @@ public void publishAsCommitted()
         }
 
         @Override
-        public void publishAsApplied()
+        public void publishAsClosed()
         {
         }
 
@@ -56,20 +57,22 @@ public boolean hasLegacyIndexChanges()
     };
 
     /**
-     * <p>
-     *     Marks the transaction as committed and makes this fact public.
-     * </p>
+     * Marks the transaction as committed and makes this fact public.
      */
     void publishAsCommitted();
 
     /**
-     * <p>
-     *     Marks the transaction as closed and makes this fact public.
-     * </p>
+     * Marks the transaction as closed and makes this fact public.
      */
-    void publishAsApplied();
+    void publishAsClosed();
 
+    /**
+     * @return whether or not {@link #publishAsCommitted()} have been called.
+     */
     boolean markedAsCommitted();
 
+    /**
+     * @return whether or not this transaction contains legacy index changes.
+     */
     boolean hasLegacyIndexChanges();
 }

community/kernel/src/main/java/org/neo4j/kernel/impl/transaction/log/TransactionAppender.java

@@ -39,15 +39,15 @@ public interface TransactionAppender
      *
      * Any failure happening inside this method will cause a {@link KernelHealth#panic(Throwable) kernel panic}.
      * Callers must make sure that successfully appended
-     * transactions exiting this method are {@link Commitment#publishAsApplied()}}.
+     * transactions exiting this method are {@link Commitment#publishAsClosed()}}.
      *
      * @param batch transactions to append to the log. These transaction instances provide both input arguments
      * as well as a place to provide output data, namely {@link TransactionToApply#commitment()} and
      * {@link TransactionToApply#transactionId()}.
      * @param logAppendEvent A trace event for the given log append operation.
      * @return last committed transaction in this batch. The appended (i.e. committed) transactions
      * will have had their {@link TransactionToApply#commitment()} available and caller is expected to
-     * {@link Commitment#publishAsApplied() mark them as applied} after they have been applied to storage.
+     * {@link Commitment#publishAsClosed() mark them as applied} after they have been applied to storage.
      * Note that {@link Commitment commitments} must be {@link Commitment#publishAsCommitted() marked as committed}
      * by this method.
      * @throws IOException if there was a problem appending the transaction. See method javadoc body for

community/kernel/src/main/java/org/neo4j/kernel/impl/transaction/log/TransactionCommitment.java

@@ -46,7 +46,7 @@ public void publishAsCommitted()
     }
 
     @Override
-    public void publishAsApplied()
+    public void publishAsClosed()
     {
         transactionIdStore.transactionClosed( transactionId,
                 logPosition.getLogVersion(), logPosition.getByteOffset() );

community/kernel/src/main/java/org/neo4j/kernel/impl/transaction/log/TransactionIdStore.java

@@ -73,12 +73,16 @@ public interface TransactionIdStore
     /**
      * Returns transaction information about the highest committed transaction, i.e.
      * transaction id as well as checksum.
+     *
+     * @return {@link TransactionId} describing the last (i.e. highest) committed transaction.
      */
     TransactionId getLastCommittedTransaction();
 
     /**
      * Returns transaction information about transaction where the last upgrade was performed, i.e.
      * transaction id as well as checksum.
+     *
+     * @return {@link TransactionId} describing the most recent upgrade transaction.
      */
     TransactionId getUpgradeTransaction();
 
@@ -90,6 +94,13 @@ public interface TransactionIdStore
     /**
      * Returns transaction information about the last committed transaction, i.e.
      * transaction id as well as the log position following the commit entry in the transaction log.
+     *
+     * @return transaction information about the last closed (highest gap-free) transaction.
+     * <pre>
+     * [0]: transaction id
+     * [1]: log version
+     * [2]: byte offset into that log version
+     * </pre>
      */
     long[] getLastClosedTransaction();
 

community/kernel/src/test/java/org/neo4j/kernel/impl/transaction/log/FakeCommitment.java

@@ -46,7 +46,7 @@ public void publishAsCommitted()
     }
 
     @Override
-    public void publishAsApplied()
+    public void publishAsClosed()
     {
         transactionIdStore.transactionClosed( id, 1, 2 );
     }

community/kernel/src/test/java/org/neo4j/kernel/impl/transaction/log/StubbedCommitment.java

@@ -36,7 +36,7 @@ public boolean markedAsCommitted()
     }
 
     @Override
-    public void publishAsApplied()
+    public void publishAsClosed()
     {
     }