false,
- * in which case you must open a new IndexReader in order
- * to see the changes. Use {@link IndexWriter#commit} to
- * commit changes to the index.
- *
- * @throws CorruptIndexException if the index is corrupt
- * @throws IOException if there is a low-level IO error
- */
public boolean isCurrent() throws CorruptIndexException, IOException {
ensureOpen();
- return SegmentInfos.readCurrentVersion(directory) == segmentInfos.getVersion();
+ if (writer == null) {
+ // we loaded SegmentInfos from the directory
+ return SegmentInfos.readCurrentVersion(directory) == segmentInfos.getVersion();
+ } else {
+ return writer.nrtIsCurrent(segmentInfosStart);
+ }
}
protected synchronized void doClose() throws IOException {
Index: src/java/org/apache/lucene/index/IndexReader.java
===================================================================
--- src/java/org/apache/lucene/index/IndexReader.java (revision 825137)
+++ src/java/org/apache/lucene/index/IndexReader.java (working copy)
@@ -468,7 +468,27 @@
}
/**
- * Version number when this IndexReader was opened. Not implemented in the IndexReader base class.
+ * Version number when this IndexReader was opened. Not
+ * implemented in the IndexReader base class.
+ *
+ * If this reader is based on a Directory (ie, was + * created by calling {@link #open}, or {@link #reopen} on + * a reader based on a Directory), then this method + * returns the version recorded in the commit that the + * reader opened. This version is advanced every time + * {@link IndexWriter#commit} is called.
+ * + *If instead this reader is a near real-time reader + * (ie, obtained by a call to {@link + * IndexWriter#getReader}, or by calling {@link #reopen} + * on a near real-time reader), then this method returns + * the version of the last commit done by the writer. + * Note that even as further changes are made with the + * writer, the version will not changed until a commit is + * completed. Thus, you should not rely on this method to + * determine when a near real-time reader should be + * opened. Use {@link #isCurrent} instead.
+ * * @throws UnsupportedOperationException unless overridden in subclass */ public long getVersion() { @@ -518,21 +538,32 @@ throw new UnsupportedOperationException("This reader does not support this method."); } + /** - * Check whether this IndexReader is still using the - * current (i.e., most recently committed) version of the - * index. If a writer has committed any changes to the - * index since this reader was opened, this will return - *false, in which case you must open a new
- * IndexReader in order to see the changes. Changes must
- * be committed using {@link IndexWriter#commit} to be
- * visible to readers.
- *
- * - * Not implemented in the IndexReader base class. - *
+ * Check whether any new changes have occurred to the + * index since this reader was opened. + * + *If this reader is based on a Directory (ie, was + * created by calling {@link #open}, or {@link #reopen} on + * a reader based on a Directory), then this method checks + * if any further commits (see {@link IndexWriter#commit} + * have occurred in that directory).
+ * + *If instead this reader is a near real-time reader + * (ie, obtained by a call to {@link + * IndexWriter#getReader}, or by calling {@link #reopen} + * on a near real-time reader), then this method checks if + * either a new commmit has occurred, or any new + * uncommitted changes have taken place via the writer. + * Note that even if the writer has only performed + * merging, this method will still return false.
+ * + *In any event, if this returns false, you should call + * {@link #reopen} to get a new reader that sees the + * changes.
+ * * @throws CorruptIndexException if the index is corrupt - * @throws IOException if there is a low-level IO error + * @throws IOException if there is a low-level IO error * @throws UnsupportedOperationException unless overridden in subclass */ public boolean isCurrent() throws CorruptIndexException, IOException { Index: src/java/org/apache/lucene/index/DocumentsWriter.java =================================================================== --- src/java/org/apache/lucene/index/DocumentsWriter.java (revision 825137) +++ src/java/org/apache/lucene/index/DocumentsWriter.java (working copy) @@ -543,6 +543,13 @@ return true; } + synchronized boolean anyChanges() { + return numDocsInRAM != 0 || + deletesInRAM.numTerms != 0 || + deletesInRAM.docIDs.size() != 0 || + deletesInRAM.queries.size() != 0; + } + synchronized private void initFlushState(boolean onlyDocStore) { initSegmentName(onlyDocStore); flushState = new SegmentWriteState(this, directory, segment, docStoreSegment, numDocsInRAM, numDocsInStore, writer.getTermIndexInterval()); Index: src/java/org/apache/lucene/index/IndexWriter.java =================================================================== --- src/java/org/apache/lucene/index/IndexWriter.java (revision 825137) +++ src/java/org/apache/lucene/index/IndexWriter.java (working copy) @@ -4961,4 +4961,14 @@ boolean testPoint(String name) { return true; } + + synchronized boolean nrtIsCurrent(SegmentInfos infos) { + if (!infos.equals(segmentInfos)) { + // if any structural changes (new segments), we are + // stale + return false; + } else { + return !docWriter.anyChanges(); + } + } }