Lucene: Compression support not configured

I got this error when trying to extract Hits.Doc from Lucene:

Compression support not configured

at SupportClass.CompressionSupport.CheckCompressionSupport()
at SupportClass.CompressionSupport.Uncompress(Byte[] input)
at Lucene.Net.Index.FieldsReader.Uncompress(Byte[] input)
at Lucene.Net.Index.FieldsReader.AddField(Document doc, FieldInfo fi, Boolean binary, Boolean compressed, Boolean tokenize)
at Lucene.Net.Index.FieldsReader.Doc(Int32 n, FieldSelector fieldSelector)
at Lucene.Net.Index.SegmentReader.Document(Int32 n, FieldSelector fieldSelector)
at Lucene.Net.Index.IndexReader.Document(Int32 n)
at Lucene.Net.Search.IndexSearcher.Doc(Int32 i)
at Lucene.Net.Search.Hits.Doc(Int32 n)

The solution was to add the following missing keys into Sitecore AppSettings.config:

<add key="Lucene.Net.FSDirectory.class" value="Sitecore.Data.Indexing.FSDirectory, Sitecore.Kernel" />
<add key="Lucene.Net.CompressionLib.class" value="Sitecore.IO.Compression, Sitecore.Kernel" />