public void testForceMergeNotNeeded() throws IOException {
try (Directory dir = newDirectory()) {
final AtomicBoolean mayMerge = new AtomicBoolean(true);
final MergeScheduler mergeScheduler =
new SerialMergeScheduler() {
@Override
public synchronized void merge(
IndexWriter writer, MergeTrigger trigger, boolean newMergesFound)
throws IOException {
if (mayMerge.get() == false) {
MergePolicy.OneMerge merge = writer.getNextMerge();
if (merge != null) {
System.out.println(
"TEST: we should not need any merging, yet merge policy returned merge "
+ merge);
throw new AssertionError();
}
}
super.merge(writer, trigger, newMergesFound);
}
};
MergePolicy mp = mergePolicy();
assumeFalse(
"this test cannot tolerate random forceMerges",
mp.toString().contains("MockRandomMergePolicy"));
mp.setNoCFSRatio(random().nextBoolean() ? 0 : 1);
IndexWriterConfig iwc = newIndexWriterConfig(new MockAnalyzer(random()));
iwc.setMergeScheduler(mergeScheduler);
iwc.setMergePolicy(mp);
IndexWriter writer = new IndexWriter(dir, iwc);
final int numSegments = TestUtil.nextInt(random(), 2, 20);
for (int i = 0; i < numSegments; ++i) {
final int numDocs = TestUtil.nextInt(random(), 1, 5);
for (int j = 0; j < numDocs; ++j) {
writer.addDocument(new Document());
}
writer.getReader().close();
}
for (int i = 5; i >= 0; --i) {
final int segmentCount = writer.getSegmentCount();
final int maxNumSegments = i == 0 ? 1 : TestUtil.nextInt(random(), 1, 10);
mayMerge.set(segmentCount > maxNumSegments);
if (VERBOSE) {
System.out.println(
"TEST: now forceMerge(maxNumSegments="
+ maxNumSegments
+ ") vs segmentCount="
+ segmentCount);
}
writer.forceMerge(maxNumSegments);
}
writer.close();
}
}
