Hi Mike, Thank you.
This exception is pretty clear that during lucene execute readInternal(...) on _0.cfs and encountered an npe. The root cause is because the object being read, FileBlock is null. As far as i can tell, it happen only during reading _0.cfs but not on the index files that were read before ( that is, for example, segments.gen, segments_1, _0.cfs). It's pretty mind boggling to understand without a better description on how lucene read the file. Tried to search in google, lucene wiki, lucene source repository on the lib and your blog but without much avail, could you give some pointer or write a general description on what happened after IndexReader reader = DirectoryReader.open(cassandraDirectory); ? 2014-02-17 16:40:48 CassandraDirectory [INFO] called length() and returning 1034 2014-02-17 16:40:48 BufferedIndexInput [INFO] length = '1034' 2014-02-17 16:40:48 CassandraDirectory [INFO] called length() and returning 1034 2014-02-17 16:40:48 CassandraDirectory [TRACE] read internal to bytes with offset 0 and length 309 2014-02-17 16:40:48 CassandraDirectory [INFO] fileDescriptor name = '_0.cfs' fileLength = '1034' 2014-02-17 16:40:48 CassandraDirectory [INFO] fileDescriptor length 1034 fileDescriptor blockSize 1 java.lang.NullPointerException at org.apache.lucene.store.CassandraDirectory$CassandraIndexInput.readInternal(CassandraDirectory.java:1850) at org.apache.lucene.store.BufferedIndexInput.readBytes(BufferedIndexInput.java:178) at org.apache.lucene.store.Directory$SlicedIndexInput.readInternal(Directory.java:306) at org.apache.lucene.store.BufferedIndexInput.refill(BufferedIndexInput.java:298) at org.apache.lucene.store.BufferedIndexInput.readByte(BufferedIndexInput.java:50) at org.apache.lucene.store.DataInput.readInt(DataInput.java:84) at org.apache.lucene.store.BufferedIndexInput.readInt(BufferedIndexInput.java:202) at org.apache.lucene.codecs.CodecUtil.checkHeader(CodecUtil.java:126) at org.apache.lucene.codecs.lucene46.Lucene46FieldInfosReader.read(Lucene46FieldInfosReader.java:56) at org.apache.lucene.index.SegmentReader.readFieldInfos(SegmentReader.java:214) at org.apache.lucene.index.SegmentReader.<init>(SegmentReader.java:94) at org.apache.lucene.index.StandardDirectoryReader$1.doBody(StandardDirectoryReader.java:62) at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:843) at org.apache.lucene.index.StandardDirectoryReader.open(StandardDirectoryReader.java:52) at org.apache.lucene.index.DirectoryReader.open(DirectoryReader.java:66) at org.apache.lucene.store.Search.<init>(Search.java:41) at org.apache.lucene.store.Search.main(Search.java:34) On Fri, Feb 14, 2014 at 7:14 PM, Michael McCandless < luc...@mikemccandless.com> wrote: > This means Lucene was attempting to open _0.fnm but somehow got the > contents of _0.cfs instead; seems likely that it's a bug in the > Cassanda Directory implementation? Somehow it's opening the wrong > file name? > > Mike McCandless > > http://blog.mikemccandless.com > > > On Fri, Feb 14, 2014 at 3:13 AM, Jason Wee <peich...@gmail.com> wrote: > > Hello, > > > > This is my first question to lucene mailing list, sorry if the question > > sounds funny. > > > > I have been experimenting to store lucene index files on cassandra, > > unfortunately the exception got overwhelmed. Below are the stacktrace. > > > > org.apache.lucene.index.CorruptIndexException: codec mismatch: actual > > codec=CompoundFileWriterData vs expected codec=Lucene46FieldInfos > > (resource: SlicedIndexInput(SlicedIndexInput(_0.fnm in > > lucene-cassandra-desc) in lucene-cassandra-desc slice=31:340)) > > at > org.apache.lucene.codecs.CodecUtil.checkHeaderNoMagic(CodecUtil.java:140) > > at org.apache.lucene.codecs.CodecUtil.checkHeader(CodecUtil.java:130) > > at > > > org.apache.lucene.codecs.lucene46.Lucene46FieldInfosReader.read(Lucene46FieldInfosReader.java:56) > > at > > > org.apache.lucene.index.SegmentReader.readFieldInfos(SegmentReader.java:214) > > at org.apache.lucene.index.SegmentReader.<init>(SegmentReader.java:94) > > at > > > org.apache.lucene.index.StandardDirectoryReader$1.doBody(StandardDirectoryReader.java:62) > > at > > > org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:843) > > at > > > org.apache.lucene.index.StandardDirectoryReader.open(StandardDirectoryReader.java:52) > > at org.apache.lucene.index.DirectoryReader.open(DirectoryReader.java:66) > > at org.apache.lucene.store.Search.<init>(Search.java:41) > > at org.apache.lucene.store.Search.main(Search.java:34) > > > > I'm not sure what does it means, can anybody help? > > > > When I check the hex representation of _0.fnm in cassandra, and > translated > > to ascii. It is something like this: > > > ??l??Lucene46FieldInfos??????path?Q??????????????PerFieldPostingsFormat.format?Lucene41?PerFieldPostingsFormat.suffix?0?modified?Q??????????????PerFieldPostingsFormat.format?Lucene41?PerFieldPostingsFormat.suffix?0?contents????????????????PerFieldPostingsFormat.format?Lucene41?PerFieldPostingsFormat.suffix?0 > > > > It looks to me the expected codec is found in the _0.fnm file or am I > wrong? > > > > Thank you and please let me know if you need additional information. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org > >
