Fixed command aggregation for legacy indexes

LegacyIndexTransactionStateImpl is responsible for tracking node/relationship
additions and removals. It uses two separate maps for this. Each map has index
name as a key and list of corresponding commands as a value. When index is
dropped, corresponding list of commands is cleared.

However additions to relationship legacy index ended up in the map dedicated
to node legacy index and removals from relationship legacy index cleared
commands from the node map. In particular this was a problem for node and
relationship indexes that had same name. It could lead to missing entries in the
legacy index after transaction completed successfully.

This commit makes LegacyIndexTransactionStateImpl use relationship map for
relationship commands.
It also improves equals/hashCode methods for legacy index commands.

community/kernel/src/main/java/org/neo4j/kernel/impl/api/state/LegacyIndexTransactionStateImpl.java

@@ -162,10 +162,10 @@ private void addCommand( String indexName, IndexCommand command, boolean clearFi
         }
         else if ( command.getEntityType() == IndexEntityType.Relationship.id() )
         {
-            commands = nodeCommands.get( indexName );
+            commands = relationshipCommands.get( indexName );
             if ( commands == null )
             {
-                nodeCommands.put( indexName, commands = new ArrayList<>() );
+                relationshipCommands.put( indexName, commands = new ArrayList<>() );
             }
         }
         else

community/kernel/src/main/java/org/neo4j/kernel/impl/index/IndexCommand.java

@@ -21,6 +21,7 @@
 
 import java.io.IOException;
 import java.util.Map;
+import java.util.Objects;
 
 import org.neo4j.graphdb.index.Index;
 import org.neo4j.kernel.impl.transaction.command.Command;
@@ -205,22 +206,28 @@ public byte endNodeNeedsLong()
         }
 
         @Override
-        public int hashCode()
+        public boolean equals( Object o )
         {
-            int result = (int) (startNode ^ (startNode >>> 32));
-            result = 31 * result + (int) (endNode ^ (endNode >>> 32));
-            return result;
+            if ( this == o )
+            {
+                return true;
+            }
+            if ( o == null || getClass() != o.getClass() )
+            {
+                return false;
+            }
+            if ( !super.equals( o ) )
+            {
+                return false;
+            }
+            AddRelationshipCommand that = (AddRelationshipCommand) o;
+            return startNode == that.startNode && endNode == that.endNode;
         }
 
         @Override
-        public boolean equals( Object obj )
+        public int hashCode()
         {
-            if ( !super.equals( obj ) )
-            {
-                return false;
-            }
-            AddRelationshipCommand other = (AddRelationshipCommand) obj;
-            return startNode == other.startNode && endNode == other.endNode;
+            return Objects.hash( super.hashCode(), startNode, endNode );
         }
 
         @Override
@@ -297,15 +304,28 @@ public Map<String, String> getConfig()
         }
 
         @Override
-        public int hashCode()
+        public boolean equals( Object o )
         {
-            return config != null ? config.hashCode() : 0;
+            if ( this == o )
+            {
+                return true;
+            }
+            if ( o == null || getClass() != o.getClass() )
+            {
+                return false;
+            }
+            if ( !super.equals( o ) )
+            {
+                return false;
+            }
+            CreateCommand that = (CreateCommand) o;
+            return Objects.equals( config, that.config );
         }
 
         @Override
-        public boolean equals( Object obj )
+        public int hashCode()
         {
-            return super.equals( obj ) && config.equals( ((CreateCommand)obj).config );
+            return Objects.hash( super.hashCode(), config );
         }
 
         @Override
@@ -323,20 +343,34 @@ public String toString()
     }
 
     @Override
-    public boolean equals( Object obj )
+    public boolean equals( Object o )
     {
-        IndexCommand other = (IndexCommand) obj;
-        boolean equals = getCommandType() == other.getCommandType() &&
-                entityType == other.entityType &&
-                indexNameId == other.indexNameId &&
-                keyId == other.keyId &&
-                getValueType() == other.getValueType();
-        if ( !equals )
+        if ( this == o )
+        {
+            return true;
+        }
+        if ( o == null || getClass() != o.getClass() )
+        {
+            return false;
+        }
+        if ( !super.equals( o ) )
         {
             return false;
         }
+        IndexCommand that = (IndexCommand) o;
+        return commandType == that.commandType &&
+               indexNameId == that.indexNameId &&
+               entityType == that.entityType &&
+               entityId == that.entityId &&
+               keyId == that.keyId &&
+               valueType == that.valueType &&
+               Objects.equals( value, that.value );
+    }
 
-        return value == null ? other.value == null : value.equals( other.value );
+    @Override
+    public int hashCode()
+    {
+        return Objects.hash( super.hashCode(), commandType, indexNameId, entityType, entityId, keyId, valueType, value );
     }
 
     public byte getCommandType()

community/kernel/src/main/java/org/neo4j/kernel/impl/index/IndexDefineCommand.java

@@ -22,6 +22,7 @@
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.neo4j.collection.primitive.Primitive;
@@ -31,7 +32,6 @@
 import org.neo4j.kernel.impl.transaction.command.NeoCommandHandler;
 
 import static java.lang.String.format;
-
 import static org.neo4j.collection.primitive.Primitive.intObjectMap;
 
 /**
@@ -142,25 +142,35 @@ private int getOrAssignId( Map<String,Integer> stringToId, PrimitiveIntObjectMap
         return id;
     }
 
-
     @Override
-    public int hashCode()
+    public boolean equals( Object o )
     {
-        int result = nextIndexNameId != null ? nextIndexNameId.hashCode() : 0;
-        result = 31 * result + (nextKeyId != null ? nextKeyId.hashCode() : 0);
-        result = 31 * result + (getIndexNameIdRange() != null ? getIndexNameIdRange().hashCode() : 0);
-        result = 31 * result + (getKeyIdRange() != null ? getKeyIdRange().hashCode() : 0);
-        result = 31 * result + (idToIndexName != null ? idToIndexName.hashCode() : 0);
-        result = 31 * result + (idToKey != null ? idToKey.hashCode() : 0);
-        return result;
+        if ( this == o )
+        {
+            return true;
+        }
+        if ( o == null || getClass() != o.getClass() )
+        {
+            return false;
+        }
+        if ( !super.equals( o ) )
+        {
+            return false;
+        }
+        IndexDefineCommand that = (IndexDefineCommand) o;
+        return nextIndexNameId.get() == that.nextIndexNameId.get() &&
+               nextKeyId.get() == that.nextKeyId.get() &&
+               Objects.equals( indexNameIdRange, that.indexNameIdRange ) &&
+               Objects.equals( keyIdRange, that.keyIdRange ) &&
+               Objects.equals( idToIndexName, that.idToIndexName ) &&
+               Objects.equals( idToKey, that.idToKey );
     }
 
     @Override
-    public boolean equals( Object obj )
+    public int hashCode()
     {
-        IndexDefineCommand other = (IndexDefineCommand) obj;
-        return getIndexNameIdRange().equals( other.getIndexNameIdRange() ) &&
-                getKeyIdRange().equals( other.getKeyIdRange() );
+        return Objects.hash( super.hashCode(), nextIndexNameId.get(), nextKeyId.get(), indexNameIdRange, keyIdRange,
+                idToIndexName, idToKey );
     }
 
     @Override