java - org.apache.lucene.index.IndexNotFoundException: no segments* file found in org.apache.lucene.store.RAMDirectory - Stack Overflow

You need to do is to explicitly call commit before opening your IndexSearcher.

    directory = new RAMDirectory();      iwriter = new IndexWriter(directory, config);      iwriter.commit();

Now Open Searcher

ireader = DirectoryReader.open(directory);  isearcher = new IndexSearcher(ireader);

Also remember you need to call commit after adding documents otherwise search may not find it. Searcher needs to reopened after commit (of course close old searcher).

iwriter.commit();

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