20 Lucene学习总结之七：Lucene有哪些信誉好的足球投注网站过程解析.doc

2.4、有哪些信誉好的足球投注网站查询对象 ? ? 2.4.2、创建Scorer及SumScorer对象树 当创建完Weight对象树的时候，调用IndexSearcher.search(Weight, Filter, int)，代码如下： //(a)创建文档号收集器 TopScoreDocCollector collector = TopScoreDocCollector.create(nDocs, !weight.scoresDocsOutOfOrder()); search(weight, filter, collector); //(b)返回有哪些信誉好的足球投注网站结果 return collector.topDocs(); public void search(Weight weight, Filter filter, Collector collector) ??? throws IOException { ? if (filter == null) { ??? for (int i = 0; i subReaders.length; i++) { ????? collector.setNextReader(subReaders[i], docStarts[i]); ????? //(c)创建Scorer对象树，以及SumScorer树用来合并倒排表 ????? Scorer scorer = weight.scorer(subReaders[i], !collector.acceptsDocsOutOfOrder(), true); ????? if (scorer != null) { ??????? //(d)合并倒排表，(e)收集文档号 ??????? scorer.score(collector); ????? } ??? } ? } else { ??? for (int i = 0; i subReaders.length; i++) { ????? collector.setNextReader(subReaders[i], docStarts[i]); ????? searchWithFilter(subReaders[i], weight, filter, collector); ??? } ? } } 在本节中，重点分析(c)创建Scorer对象树，以及SumScorer树用来合并倒排表，在2.4.3节中，分析 (d)合并倒排表，在2.4.4节中，分析文档结果收集器的创建(a)，结果文档的收集(e)，以及文档的返回(b)。 BooleanQuery$BooleanWeight.scorer(IndexReader, boolean, boolean) 代码如下： public Scorer scorer(IndexReader reader, boolean scoreDocsInOrder, boolean topScorer){ ? //存放对应于MUST语句的Scorer ? ListScorer required = new ArrayListScorer(); ? //存放对应于MUST_NOT语句的Scorer ? ListScorer prohibited = new ArrayListScorer(); ? //存放对应于SHOULD语句的Scorer ? ListScorer optional = new ArrayListScorer(); ? //遍历每一个子语句，生成子Scorer对象，并加入相应的集合，这是一个递归的过程。 ? IteratorBooleanClause cIter = clauses.iterator(); ? for (Weight w? : weights) { ??? BooleanClause c =? cIter.next(); ??? Scorer subScorer = w.scorer(reader, true, false); ??? if (subScorer == null) { ????? if (c.isRequired()) { ??????? return null; ????? } ??? } else if (c.isRequired()) { ????? required.add(subScorer); ??? } else if (c.isProhibited()) { ????? prohibited.add(subScorer); ??? } else { ????? optional.add(subScorer); ??? } ? } ? //此处在有关BooleanScorer及scoreDocsInOrder一节会详细描述 ? if