Java LeafReader.postings方法代码示例

import org.apache.lucene.index.LeafReader; //导入方法依赖的package包/类
public static void printAnnotations(LeafReader reader, Term term) throws IOException {
    System.out.println("Annotations for " + term);
    final ByteArrayDataInput in = new ByteArrayDataInput();
    final PostingsEnum postings = reader.postings(term, PostingsEnum.PAYLOADS);
    for (int docID = postings.nextDoc(); docID != DocIdSetIterator.NO_MORE_DOCS; docID = postings.nextDoc()) {
        final int freq = postings.freq();
        System.out.println("  doc=" + docID + ", freq=" + freq);
        for (int i = 0; i < freq; i++) {
            postings.nextPosition();
            final BytesRef payload = postings.getPayload();
            in.reset(payload.bytes, payload.offset, payload.length);
            System.out.println("    start=" + in.readVInt() + ", length=" + in.readVInt());
        }
    }
}
 

import org.apache.lucene.index.LeafReader; //导入方法依赖的package包/类
private void executeNeedleTests(Analyzer analyzer) throws Exception {

    String needle = getNeedle(analyzer);
    int numFieldValues = 23;

    Directory directory = buildNeedleIndex(needle, analyzer, numFieldValues);

    IndexReader reader = DirectoryReader.open(directory);

    LeafReaderContext ctx = reader.leaves().get(0);
    LeafReader r = ctx.reader();

    PostingsEnum dpe = r.postings(new Term(FIELD, needle), PostingsEnum.ALL);
    int numTests = 0;
    try {
      while (dpe.nextDoc() != DocIdSetIterator.NO_MORE_DOCS) {
        int frq = dpe.freq();
        int advanced = 0;

        String[] fieldValues = r.document(dpe.docID()).getValues(FIELD);
        while (++advanced < frq) {
          dpe.nextPosition();
          String rebuilt = SimpleAnalyzerUtil.substringFromMultiValuedFields(dpe.startOffset(),
              dpe.endOffset(), fieldValues, analyzer.getOffsetGap(FIELD), " | ");
          assertEquals(needle, rebuilt);
          numTests++;
        }
      }
    } finally {
      reader.close();
      directory.close();
    }
    assertEquals("number of tests", numFieldValues - 1, numTests);
  }
 

import org.apache.lucene.index.LeafReader; //导入方法依赖的package包/类
@SuppressWarnings("resource")
public static void main(String[] args) throws Exception {
    final Directory dir = new RAMDirectory();
    final IndexWriterConfig conf = new IndexWriterConfig(new WhitespaceAnalyzer());
    final IndexWriter writer = new IndexWriter(dir, conf);

    final Document doc = new Document();
    doc.add(new TextField("f", new TokenStream() {
        final PositionIncrementAttribute pos = addAttribute(PositionIncrementAttribute.class);
        final CharTermAttribute term = addAttribute(CharTermAttribute.class);
        boolean first = true, done = false;

        @Override
        public boolean incrementToken() throws IOException {
            if (done) {
                return false;
            }
            if (first) {
                term.setEmpty().append("a");
                pos.setPositionIncrement(1);
                first = false;
            } else {
                term.setEmpty().append("b");
                pos.setPositionIncrement(0);
                done = true;
            }
            return true;
        }
    }));
    writer.addDocument(doc);
    writer.close();

    final DirectoryReader reader = DirectoryReader.open(dir);
    final IndexSearcher searcher = new IndexSearcher(reader);
    final LeafReader ar = reader.leaves().get(0).reader();
    final TermsEnum te = ar.terms("f").iterator();
    BytesRef scratch = new BytesRef();
    while ((scratch = te.next()) != null) {
        System.out.println(scratch.utf8ToString());
        final PostingsEnum dape = ar.postings(new Term("f", scratch.utf8ToString()));
        System.out.println("  doc=" + dape.nextDoc() + ", pos=" + dape.nextPosition());
    }

    System.out.println();

    // try a phrase query with a slop
    final PhraseQuery pqNoSlop = buildPhraseQuery(0);
    System.out.println("searching for \"a b\"; num results = " + searcher.search(pqNoSlop, 10).totalHits);

    final PhraseQuery pqSlop1 = buildPhraseQuery(1);
    System.out.println("searching for \"a b\"~1; num results = " + searcher.search(pqSlop1, 10).totalHits);

    final PhraseQuery pqSlop3 = buildPhraseQuery(3);
    System.out.println("searching for \"a b\"~3; num results = " + searcher.search(pqSlop3, 10).totalHits);

    final SpanNearQuery snqUnOrdered =
            new SpanNearQuery(new SpanQuery[] { new SpanTermQuery(new Term("f", "a")),
                    new SpanTermQuery(new Term("f", "b")) }, 1, false);
    System.out.println("searching for SpanNearUnordered('a', 'b'), slop=1; num results = "
            + searcher.search(snqUnOrdered, 10).totalHits);

    final SpanNearQuery snqOrdered = new SpanNearQuery(new SpanQuery[] { new SpanTermQuery(new Term("f", "a")),
            new SpanTermQuery(new Term("f", "b")) }, 1, true);
    System.out.println("searching for SpanNearOrdered('a', 'b'), slop=1; num results = "
            + searcher.search(snqOrdered, 10).totalHits);

    reader.close();
}