Combined error handling in single object

Author: pontusmelke

driver/src/main/java/org/neo4j/driver/internal/ClusterDriver.java

@@ -198,21 +198,20 @@ public Session session()
     public Session session( final AccessMode mode )
     {
         return new ClusteredNetworkSession( acquireConnection( mode ),
-                new Consumer<BoltServerAddress>()
+                new ClusteredErrorHandler()
                 {
                     @Override
-                    public void accept( BoltServerAddress address )
+                    public void onConnectionFailure( BoltServerAddress address )
                     {
                         forget( address );
                     }
-                }, new Consumer<BoltServerAddress>()
-        {
-            @Override
-            public void accept( BoltServerAddress address )
-            {
-                writeServers.remove( address );
-            }
-        },
+
+                    @Override
+                    public void onWriteFailure( BoltServerAddress address )
+                    {
+                        writeServers.remove( address );
+                    }
+                },
                 log );
     }
 

driver/src/main/java/org/neo4j/driver/internal/ClusteredErrorHandler.java

@@ -0,0 +1,31 @@
+/**
+ * Copyright (c) 2002-2016 "Neo Technology,"
+ * Network Engine for Objects in Lund AB [http://neotechnology.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.neo4j.driver.internal;
+
+import org.neo4j.driver.internal.net.BoltServerAddress;
+
+/**
+ * Interface used for tracking errors when connected to a cluster.
+ */
+interface ClusteredErrorHandler
+{
+    void onConnectionFailure( BoltServerAddress address );
+
+    void onWriteFailure( BoltServerAddress address );
+}

driver/src/main/java/org/neo4j/driver/internal/ClusteredNetworkSession.java

@@ -21,7 +21,6 @@
 
 import org.neo4j.driver.internal.net.BoltServerAddress;
 import org.neo4j.driver.internal.spi.Connection;
-import org.neo4j.driver.internal.util.Consumer;
 import org.neo4j.driver.v1.Logger;
 import org.neo4j.driver.v1.Statement;
 import org.neo4j.driver.v1.StatementResult;
@@ -31,36 +30,32 @@
 
 public class ClusteredNetworkSession extends NetworkSession
 {
-    private final Consumer<BoltServerAddress> onFailedConnection;
-    private final Consumer<BoltServerAddress> onFailedWrite;
+    private final ClusteredErrorHandler onError;
 
-    //TODO combine failure handling
     ClusteredNetworkSession( Connection connection,
-            Consumer<BoltServerAddress> onFailedConnection,
-            Consumer<BoltServerAddress> onFailedWrite, Logger logger )
+            ClusteredErrorHandler onError, Logger logger )
     {
         super( connection, logger );
-        this.onFailedConnection = onFailedConnection;
-        this.onFailedWrite = onFailedWrite;
+        this.onError = onError;
     }
 
     @Override
     public StatementResult run( Statement statement )
     {
         try
         {
-            return new ClusteredStatementResult( super.run( statement ), connection.address(), onFailedConnection, onFailedWrite);
+            return new ClusteredStatementResult( super.run( statement ), connection.address(), onError );
         }
         catch ( ConnectionFailureException e )
         {
-            onFailedConnection.accept( connection.address() );
+            onError.onConnectionFailure( connection.address() );
             throw new SessionExpiredException( "Failed to perform write load to server", e );
         }
         catch ( ClientException e )
         {
             if ( e.code().equals( "Neo.ClientError.General.ForbiddenOnFollower" ) )
             {
-                onFailedWrite.accept( connection.address() );
+                onError.onWriteFailure( connection.address() );
                 throw new SessionExpiredException(
                         String.format( "Server at %s no longer accepts writes", connection.address().toString() ) );
             }
@@ -81,8 +76,9 @@ public void close()
         catch ( ConnectionFailureException e )
         {
             BoltServerAddress address = connection.address();
-            onFailedConnection.accept( address );
-            throw new SessionExpiredException( String.format( "Server at %s is no longer available", address.toString()), e);
+            onError.onConnectionFailure( address );
+            throw new SessionExpiredException(
+                    String.format( "Server at %s is no longer available", address.toString() ), e );
         }
     }
 }

driver/src/main/java/org/neo4j/driver/internal/ClusteredStatementResult.java

@@ -21,7 +21,6 @@
 import java.util.List;
 
 import org.neo4j.driver.internal.net.BoltServerAddress;
-import org.neo4j.driver.internal.util.Consumer;
 import org.neo4j.driver.v1.Record;
 import org.neo4j.driver.v1.StatementResult;
 import org.neo4j.driver.v1.exceptions.ClientException;
@@ -35,15 +34,13 @@ public class ClusteredStatementResult implements StatementResult
 {
     private final StatementResult delegate;
     private final BoltServerAddress address;
-    private final Consumer<BoltServerAddress> onFailedConnection;
-    private final Consumer<BoltServerAddress> onFailedWrite;
+    private final ClusteredErrorHandler onError;
 
-    ClusteredStatementResult( StatementResult delegate, BoltServerAddress address, Consumer<BoltServerAddress> onFailedConnection, Consumer<BoltServerAddress> onFailedWrite)
+    ClusteredStatementResult( StatementResult delegate, BoltServerAddress address, ClusteredErrorHandler onError )
     {
         this.delegate = delegate;
         this.address = address;
-        this.onFailedConnection = onFailedConnection;
-        this.onFailedWrite = onFailedWrite;
+        this.onError = onError;
     }
 
     @Override
@@ -241,14 +238,13 @@ public ResultSummary consume()
 
     private SessionExpiredException sessionExpired( ConnectionFailureException e )
     {
-        onFailedConnection.accept( address );
+        onError.onConnectionFailure( address );
         return new SessionExpiredException( String.format( "Server at %s is no longer available", address.toString()), e);
     }
 
     private SessionExpiredException failedWrite()
     {
-
-        onFailedWrite.accept( address );
+        onError.onWriteFailure( address );
         return new SessionExpiredException( String.format( "Server at %s no longer accepts writes", address.toString()));
     }