在創(chuàng)建索引的時候分為了許多Field列，在查詢的時候可以同時查詢這些列，然后使用布爾邏輯查詢將這些查詢返回的結(jié)果合并。

在沒有使用布爾邏輯查詢之前的代碼：

public void seacher(String queryString) throws IOException, ParseException {
        String field[] = { "title", "content", "author" };
        for (int i = 0; i < field.length; i++) {
            String defualtField = field[i];
            TopDocs topDocs = null;

            IndexReader reader = DirectoryReader.open(
                  FSDirectory.open(Paths.get(indexPath)));
            IndexSearcher searcher = new IndexSearcher(reader);

            Analyzer analyzer = getAnalyzer();
            //QueryParser是用來解析查詢串
            QueryParser queryParser 
                = new QueryParser(defualtField, analyzer);
            Query query = queryParser.parse(queryString);
            //返回最相關(guān)的10個文檔
            topDocs = searcher.search(query, 10);

            ScoreDoc[] hits = topDocs.scoreDocs;
            for (ScoreDoc hit : hits) {
                Document hitDoc = searcher.doc(hit.doc);
                System.out.println(hitDoc.get("title") 
                      + " " + hitDoc.get("url"));
            }
        }
    }

得到的結(jié)果為：

會將重復的結(jié)果也展示

改為布爾邏輯查詢：

    public void seacher(String queryString) throws IOException, ParseException {
        TopDocs topDocs = null;

        IndexReader reader = DirectoryReader.open(
                     FSDirectory.open(Paths.get(indexPath)));
        IndexSearcher searcher = new IndexSearcher(reader);

        Analyzer analyzer = getAnalyzer();
        // QueryParser是用來解析查詢串
        QueryParser queryParser = new QueryParser("title", analyzer);
        Query titleQuery = queryParser.parse(queryString);// 查詢標題列

        queryParser = new QueryParser("content", analyzer);// 查詢內(nèi)容列
        Query contentQuery = queryParser.parse(queryString);

        queryParser = new QueryParser("autor", analyzer);// 查詢作者列
        Query authorQuery = queryParser.parse(queryString);
        
        // 使用布爾邏輯查詢
        
        BooleanQuery.Builder queryBuild=new BooleanQuery.Builder();
        queryBuild.add(titleQuery,BooleanClause.Occur.SHOULD);
        queryBuild.add(contentQuery,BooleanClause.Occur.SHOULD);
        queryBuild.add(authorQuery,BooleanClause.Occur.SHOULD);
        
        BooleanQuery query=queryBuild.build();
        // 返回最相關(guān)的10個文檔
        topDocs = searcher.search(query, 10);

        ScoreDoc[] hits = topDocs.scoreDocs;
        for (ScoreDoc hit : hits) {
            Document hitDoc = searcher.doc(hit.doc);
            System.out.println(hitDoc.get("title") 
                      + " " + hitDoc.get("url"));
        }
    }

將重復的結(jié)果去掉了

在Lucene 6.1.0使用布爾邏輯查詢可以先創(chuàng)建一個BooleanQuery.Builder對象，通過add方法將之前的創(chuàng)建的查詢加入到該對象中，然后再調(diào)用build()方法轉(zhuǎn)換為BooleanQuery 對象。

一共有4種Occur方式：

    /** Use this operator for clauses that <i>must</i> appear in the matching documents. */
    MUST     { @Override public String toString() { return "+"; } },

    /** Like {@link #MUST} except that these clauses do not participate in scoring. */
    FILTER   { @Override public String toString() { return "#"; } },

    /** Use this operator for clauses that <i>should</i> appear in the 
     * matching documents. For a BooleanQuery with no <code>MUST</code> 
     * clauses one or more <code>SHOULD</code> clauses must match a document 
     * for the BooleanQuery to match.
     * @see BooleanQuery.Builder#setMinimumNumberShouldMatch
     */
    SHOULD   { @Override public String toString() { return "";  } },

    /** Use this operator for clauses that <i>must not</i> appear in the matching documents.
     * Note that it is not possible to search for queries that only consist
     * of a <code>MUST_NOT</code> clause. These clauses do not contribute to the
     * score of documents. */
　　 MUST_NOT { @Override public String toString() { return "-"; } };

SHOULD是析取查詢，選擇出包含任何一個查詢詞的文檔；
　　MUST_NOT是否定查詢，即不包括符合這個條件的文檔。
　　
　　BooleanQuery對象還可以設(shè)置最小匹配數(shù)量，只要設(shè)置minimumNumberShouldMatch屬性即可（在構(gòu)造函數(shù)中設(shè)置）。