/* A Possible future optimization could skip entire segments */
public boolean skipTo(int target) throws IOException {
for (; ; ) {
if (current != null && current.skipTo(target - base)) {
return true;
} else if (pointer < readers.length) {
if (tenum != null) {
SegmentMergeInfo smi = tenum.matchingSegments[matchingSegmentPos++];
if (smi == null) {
pointer = readers.length;
return false;
}
pointer = smi.ord;
}
base = starts[pointer];
current = termDocs(pointer++);
} else return false;
}
}
public void testSkipTo(int indexDivisor) throws IOException {
Directory dir = new RAMDirectory();
IndexWriter writer =
new IndexWriter(dir, new WhitespaceAnalyzer(), true, IndexWriter.MaxFieldLength.LIMITED);
Term ta = new Term("content", "aaa");
for (int i = 0; i < 10; i++) addDoc(writer, "aaa aaa aaa aaa");
Term tb = new Term("content", "bbb");
for (int i = 0; i < 16; i++) addDoc(writer, "bbb bbb bbb bbb");
Term tc = new Term("content", "ccc");
for (int i = 0; i < 50; i++) addDoc(writer, "ccc ccc ccc ccc");
// assure that we deal with a single segment
writer.optimize();
writer.close();
IndexReader reader = IndexReader.open(dir);
reader.setTermInfosIndexDivisor(indexDivisor);
assertEquals(indexDivisor, reader.getTermInfosIndexDivisor());
TermDocs tdocs = reader.termDocs();
// without optimization (assumption skipInterval == 16)
// with next
tdocs.seek(ta);
assertTrue(tdocs.next());
assertEquals(0, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.next());
assertEquals(1, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.skipTo(0));
assertEquals(2, tdocs.doc());
assertTrue(tdocs.skipTo(4));
assertEquals(4, tdocs.doc());
assertTrue(tdocs.skipTo(9));
assertEquals(9, tdocs.doc());
assertFalse(tdocs.skipTo(10));
// without next
tdocs.seek(ta);
assertTrue(tdocs.skipTo(0));
assertEquals(0, tdocs.doc());
assertTrue(tdocs.skipTo(4));
assertEquals(4, tdocs.doc());
assertTrue(tdocs.skipTo(9));
assertEquals(9, tdocs.doc());
assertFalse(tdocs.skipTo(10));
// exactly skipInterval documents and therefore with optimization
// with next
tdocs.seek(tb);
assertTrue(tdocs.next());
assertEquals(10, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.next());
assertEquals(11, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.skipTo(5));
assertEquals(12, tdocs.doc());
assertTrue(tdocs.skipTo(15));
assertEquals(15, tdocs.doc());
assertTrue(tdocs.skipTo(24));
assertEquals(24, tdocs.doc());
assertTrue(tdocs.skipTo(25));
assertEquals(25, tdocs.doc());
assertFalse(tdocs.skipTo(26));
// without next
tdocs.seek(tb);
assertTrue(tdocs.skipTo(5));
assertEquals(10, tdocs.doc());
assertTrue(tdocs.skipTo(15));
assertEquals(15, tdocs.doc());
assertTrue(tdocs.skipTo(24));
assertEquals(24, tdocs.doc());
assertTrue(tdocs.skipTo(25));
assertEquals(25, tdocs.doc());
assertFalse(tdocs.skipTo(26));
// much more than skipInterval documents and therefore with optimization
// with next
tdocs.seek(tc);
assertTrue(tdocs.next());
assertEquals(26, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.next());
assertEquals(27, tdocs.doc());
assertEquals(4, tdocs.freq());
assertTrue(tdocs.skipTo(5));
assertEquals(28, tdocs.doc());
assertTrue(tdocs.skipTo(40));
assertEquals(40, tdocs.doc());
assertTrue(tdocs.skipTo(57));
assertEquals(57, tdocs.doc());
assertTrue(tdocs.skipTo(74));
assertEquals(74, tdocs.doc());
assertTrue(tdocs.skipTo(75));
assertEquals(75, tdocs.doc());
assertFalse(tdocs.skipTo(76));
// without next
tdocs.seek(tc);
assertTrue(tdocs.skipTo(5));
assertEquals(26, tdocs.doc());
assertTrue(tdocs.skipTo(40));
assertEquals(40, tdocs.doc());
assertTrue(tdocs.skipTo(57));
assertEquals(57, tdocs.doc());
assertTrue(tdocs.skipTo(74));
assertEquals(74, tdocs.doc());
assertTrue(tdocs.skipTo(75));
assertEquals(75, tdocs.doc());
assertFalse(tdocs.skipTo(76));
tdocs.close();
reader.close();
dir.close();
}