Fixes a -1 short -> int conversion issue w/ legacy index key id

where we'd like to treat the short as unsigned, except for the value -1.
This commit ensure that -1 gets recognized properly.

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

@@ -30,7 +30,6 @@
 import org.neo4j.kernel.impl.transaction.command.CommandRecordVisitor;
 import org.neo4j.kernel.impl.transaction.command.NeoCommandHandler;
 
-import static java.lang.Math.pow;
 import static java.lang.String.format;
 
 import static org.neo4j.collection.primitive.Primitive.intObjectMap;
@@ -47,6 +46,7 @@
  */
 public class IndexDefineCommand extends Command
 {
+    static final int HIGHEST_POSSIBLE_ID = 0xFFFF - 1; // -1 since the actual value -1 is reserved for all-ones
     private final AtomicInteger nextIndexNameId = new AtomicInteger();
     private final AtomicInteger nextKeyId = new AtomicInteger();
     private Map<String,Integer> indexNameIdRange;
@@ -129,11 +129,11 @@ private int getOrAssignId( Map<String,Integer> stringToId, PrimitiveIntObjectMap
         }
 
         int nextIdInt = nextId.incrementAndGet();
-        if ( (nextIdInt & ~0xFFFF) != 0 )
+        if ( nextIdInt > HIGHEST_POSSIBLE_ID ) // >= since the actual value -1 is reserved for all-ones
         {
             throw new IllegalStateException( format(
                     "Modifying more than %d indexes in a single transaction is not supported",
-                    (int)(pow( 2, 16 ) - 1) ) );
+                    HIGHEST_POSSIBLE_ID + 1 ) );
         }
         id = nextIdInt;
 

community/kernel/src/main/java/org/neo4j/kernel/impl/transaction/command/PhysicalLogNeoCommandReaderV2_2_4.java

@@ -695,7 +695,8 @@ private Map<String,Integer> readMap( ReadableLogChannel channel ) throws IOExcep
 
     private int getUnsignedShort( ReadableLogChannel channel ) throws IOException
     {
-        return channel.getShort() & 0xFFFF;
+        int result = channel.getShort() & 0xFFFF;
+        return result == 0xFFFF ? -1 : result;
     }
 
     private IndexCommandHeader readIndexCommandHeader() throws ReadPastEndException, IOException

community/kernel/src/test/java/org/neo4j/kernel/impl/index/IndexDefineCommandTest.java

@@ -30,20 +30,31 @@ public void testIndexCommandCreationEnforcesLimit() throws Exception
     {
         // Given
         IndexDefineCommand idc = new IndexDefineCommand();
-        int max = (int) (Math.pow( 2, 16 ) - 1);
+        int count = IndexDefineCommand.HIGHEST_POSSIBLE_ID;
 
         // When
-        for ( int i = 0; i < max; i++ )
+        for ( int i = 0; i < count; i++ )
         {
-            idc.getOrAssignKeyId( "index" + i );
+            idc.getOrAssignKeyId( "key" + i );
+            idc.getOrAssignIndexNameId( "index" + i );
         }
 
         // Then
-        // it should break on the 64th
+        // it should break on too many
         try
         {
             idc.getOrAssignKeyId( "dropThatOverflows" );
-            fail( "IndexDefineCommand should not allow more than 63 indexes per transaction" );
+            fail( "IndexDefineCommand should not allow more than " + count + " indexes per transaction" );
+        }
+        catch( IllegalStateException e )
+        {
+            // wonderful
+        }
+
+        try
+        {
+            idc.getOrAssignIndexNameId( "dropThatOverflows" );
+            fail( "IndexDefineCommand should not allow more than " + count + " keys per transaction" );
         }
         catch( IllegalStateException e )
         {

community/kernel/src/test/java/org/neo4j/kernel/impl/transaction/command/PhysicalLogNeoCommandReaderV2_2_4Test.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2002-2015 "Neo Technology,"
+ * Network Engine for Objects in Lund AB [http://neotechnology.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.kernel.impl.transaction.command;
+
+import org.junit.Test;
+
+import org.neo4j.helpers.collection.MapUtil;
+import org.neo4j.kernel.impl.index.IndexCommand;
+import org.neo4j.kernel.impl.index.IndexCommand.RemoveCommand;
+import org.neo4j.kernel.impl.index.IndexDefineCommand;
+import org.neo4j.kernel.impl.index.IndexEntityType;
+import org.neo4j.kernel.impl.transaction.log.CommandWriter;
+import org.neo4j.kernel.impl.transaction.log.InMemoryLogChannel;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+public class PhysicalLogNeoCommandReaderV2_2_4Test
+{
+    @Test
+    public void shouldReadNoKeyIdAsMinusOne() throws Exception
+    {
+        // GIVEN
+        InMemoryLogChannel channel = new InMemoryLogChannel();
+        CommandWriter writer = new CommandWriter( channel );
+        IndexDefineCommand definitions = new IndexDefineCommand();
+        int indexNameId = 10;
+        definitions.init(
+                MapUtil.<String,Integer>genericMap( "myindex", indexNameId ),
+                MapUtil.<String,Integer>genericMap() );
+        writer.visitIndexDefineCommand( definitions );
+        RemoveCommand removeCommand = new IndexCommand.RemoveCommand();
+        removeCommand.init( indexNameId, IndexEntityType.Node.id(), 1234, -1, null );
+        writer.visitIndexRemoveCommand( removeCommand );
+
+        // WHEN
+        PhysicalLogNeoCommandReaderV2_2_4 reader = new PhysicalLogNeoCommandReaderV2_2_4();
+        assertTrue( reader.read( channel ) instanceof IndexDefineCommand );
+        RemoveCommand readRemoveCommand = (RemoveCommand) reader.read( channel );
+
+        // THEN
+        assertEquals( removeCommand.getIndexNameId(), readRemoveCommand.getIndexNameId() );
+        assertEquals( removeCommand.getEntityType(), readRemoveCommand.getEntityType() );
+        assertEquals( removeCommand.getEntityId(), readRemoveCommand.getEntityId() );
+        assertEquals( removeCommand.getKeyId(), readRemoveCommand.getKeyId() );
+        assertNull( removeCommand.getValue() );
+    }
+}