| # Apache Lucene Migration Guide |
| |
| ## Separation of IndexDocument and StoredDocument (LUCENE-3312) |
| |
| The API of oal.document was restructured to differentiate between stored |
| documents and indexed documents. IndexReader.document(int) now returns |
| StoredDocument instead of Document. In most cases a simple replacement |
| of the return type is enough to upgrade. |
| |
| ## Removed Reader from Tokenizer constructor (LUCENE-5388) |
| |
| The constructor of Tokenizer no longer takes Reader, as this was a leftover |
| from before it was reusable. See the org.apache.lucene.analysis package |
| documentation for more details. |
| |
| ## Refactored Collector API (LUCENE-5299) |
| |
| The Collector API has been refactored to use a different Collector instance |
| per segment. It is possible to migrate existing collectors painlessly by |
| extending SimpleCollector instead of Collector: SimpleCollector is a |
| specialization of Collector that returns itself as a per-segment Collector. |
| |
| ## IndexWriter.close now discards all changes and closes, even on exception (LUCENE-4246) |
| |
| When you close an IndexWriter it will discard all changes; you must |
| call .commit() and .waitForMerges() beforehand. If |
| IndexWriterConfig's matchVersion is before 5.0, then close will |
| throw an exception indicating that changes were lost (but the |
| IndexWriter will still have been closed). |
