Hello, I have a ToParentBlockJoinQuery and I want to sort the results by one of the child fields. I have: ToParentBlockJoinSortField
Sometimes it works good. And sometimes I have a strange error. Maybe you can guess what's going on based on the stack trace. If not - I created an example here: https://github.com/jamerlan/LuceneNestedSearchError It fails on: "parents.length()" because parents is null. Lucene version: 6.6.0 Exception in thread "main" java.lang.NullPointerException at org.apache.lucene.search.join.BlockJoinSelector.wrap(BlockJoinSelector.java:161) at org.apache.lucene.search.join.ToParentBlockJoinSortField$3.getNumericDocValues(ToParentBlockJoinSortField.java:168) at org.apache.lucene.search.FieldComparator$NumericComparator.doSetNextReader(FieldComparator.java:153) at org.apache.lucene.search.SimpleFieldComparator.getLeafComparator(SimpleFieldComparator.java:36) at org.apache.lucene.search.FieldValueHitQueue.getComparators(FieldValueHitQueue.java:180) at org.apache.lucene.search.TopFieldCollector$SimpleFieldCollector.getLeafCollector(TopFieldCollector.java:100) at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:659) at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:472) at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:591) at org.apache.lucene.search.IndexSearcher.searchAfter(IndexSearcher.java:576) at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:491) at parentchild.StrangeErrorTest.main(StrangeErrorTest.java:87) Strange thing is: If you comment out this block: BookStore bs2 = new BookStore(2, "second"); BookStoreInfo bookStoreInfo2 = new BookStoreInfo(20, "book 2"); index(searcherManager, indexWriter, bs2, bookStoreInfo2); then it works. Thank you for help!
