[LUCENE-5931] DirectoryReader.openIfChanged(oldReader, commit) incorrectly assumes given commit point has deletes/field updates

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 4.6.1
• Fix Version/s: 6.2, 7.0
• Component/s: core/index
• Lucene Fields: New
• Assignee: Michael McCandless
• Reporter: Vitaly Funstein
• Created: 10/Sep/14 01:01
• Updated: 28/Aug/22 14:15
• Resolved: 12/Jun/16 21:02

Description

StandardDirectoryReader assumes that the segments from commit point have deletes, when they may not, yet the original SegmentReader for the segment that we are trying to reuse does. This is evident when running attached JUnit test case with asserts enabled (default):

java.lang.AssertionError
	at org.apache.lucene.index.StandardDirectoryReader.open(StandardDirectoryReader.java:188)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenIfChanged(StandardDirectoryReader.java:326)
	at org.apache.lucene.index.StandardDirectoryReader$2.doBody(StandardDirectoryReader.java:320)
	at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:702)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenFromCommit(StandardDirectoryReader.java:315)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenNoWriter(StandardDirectoryReader.java:311)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenIfChanged(StandardDirectoryReader.java:262)
	at org.apache.lucene.index.DirectoryReader.openIfChanged(DirectoryReader.java:183)

or, if asserts are disabled then it falls through into NPE:

java.lang.NullPointerException
	at java.io.File.<init>(File.java:305)
	at org.apache.lucene.store.NIOFSDirectory.openInput(NIOFSDirectory.java:80)
	at org.apache.lucene.codecs.lucene40.BitVector.<init>(BitVector.java:327)
	at org.apache.lucene.codecs.lucene40.Lucene40LiveDocsFormat.readLiveDocs(Lucene40LiveDocsFormat.java:90)
	at org.apache.lucene.index.SegmentReader.<init>(SegmentReader.java:131)
	at org.apache.lucene.index.StandardDirectoryReader.open(StandardDirectoryReader.java:194)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenIfChanged(StandardDirectoryReader.java:326)
	at org.apache.lucene.index.StandardDirectoryReader$2.doBody(StandardDirectoryReader.java:320)
	at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:702)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenFromCommit(StandardDirectoryReader.java:315)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenNoWriter(StandardDirectoryReader.java:311)
	at org.apache.lucene.index.StandardDirectoryReader.doOpenIfChanged(StandardDirectoryReader.java:262)
	at org.apache.lucene.index.DirectoryReader.openIfChanged(DirectoryReader.java:183)