/* * listPostings displays the first n postings for a term in a * field in an index (specified by reader). Set n to MAX_VALUE * to display all postings. */ static void listPostings(IndexReader reader, String termString, String field, Integer n) throws IOException { System.out.println("\nPostings: " + termString + " " + field); /* * Prepare to access the index. */ BytesRef termBytes = new BytesRef(termString); Term term = new Term(field, termBytes); Bits liveDocs = MultiFields.getLiveDocs(reader); /* * Lookup the collection term frequency (ctf). */ long df = reader.docFreq(term); System.out.println("\tdf: " + df); long ctf = reader.totalTermFreq(term); System.out.println("\tctf: " + ctf); if (df < 1) return; /* * Lookup the inverted list. */ DocsAndPositionsEnum postings = MultiFields.getTermPositionsEnum(reader, liveDocs, field, termBytes); /* * Iterate through the first n postings. */ long count = 0; while ((count < n) && (postings.nextDoc() != DocIdSetIterator.NO_MORE_DOCS)) { System.out.println("\tdocid: " + postings.docID()); int tf = postings.freq(); System.out.println("\ttf: " + tf); System.out.print("\tPositions: "); for (int j = 0; j < tf; j++) { int pos = postings.nextPosition(); System.out.print(pos + " "); } System.out.println(""); count++; } ; return; }