lucene的多种搜索

关键字: termquery, phrasequery, wildcardquery, fuzzyquery, prefixquery, rangequery, booleanquery, phraseprefixquery, multifieldqueryparser

lucene的搜索相当强大,它提供了很多辅助查询类,各自完成一种特殊的查询,也可以相互组合使用,来完成一些复杂的操作.

 

 

public class Test{

    Analyzer analyzer = new StandardAnalyzer();

    RAMDirectory directory = new RAMDirectory();

    /**
     * 创建索引
     *
     * @throws IOException
     */
    public void index() throws IOException{

        IndexWriter indexWriter = new IndexWriter(directory,analyzer,true);

        Document doc1 = new Document();

        doc1.add(new Field("title","aaabbb",Store.YES,Index.TOKENIZED));

        doc1.add(new Field("content","If you would like to help promote OpenOffice",Store.YES,Index.TOKENIZED));

        doc1.add(new Field("time","2005",Store.YES,Index.TOKENIZED));

        indexWriter.addDocument(doc1);

        Document doc2 = new Document();

        doc2.add(new Field("title","bbcc",Store.YES,Index.TOKENIZED));

        doc2.add(new Field("content","sdfsdfsdfasdds",Store.YES,Index.TOKENIZED));

        doc2.add(new Field("time","2007",Store.YES,Index.TOKENIZED));

        indexWriter.addDocument(doc2);

        indexWriter.optimize();

        indexWriter.close();
    }

    // 按词条搜索
    public void termSearcher() throws IOException{

        IndexSearcher searcher = new IndexSearcher(directory);

        // 查询title中包含aaa
        Term term = new Term("title","aaa");

        Query query = new TermQuery(term);

        searcher.search(query);

        searcher.close();
    }

    // 短语搜索
    public void phraseSearcher() throws IOException{

        IndexSearcher searcher = new IndexSearcher(directory);

        PhraseQuery phraseQuery = new PhraseQuery();

        // slop 两个项的位置之间允许的最大间隔,这里would和help中间只隔了like(to会被去掉),所以最大间隔设为1就能找到值
        // 对于两个相连的关键词来说,无论坡度设为多少,都可以找到
        // 对于不相连的词来说,当两个关键词相隔数小于坡度都可以找到,否则找不到
        phraseQuery.setSlop(1);

        phraseQuery.add(new Term("content","would"));

        phraseQuery.add(new Term("content","help"));

        // 如果将help放前面,would放后面,需要将would向后移动3个位置才能到help后面(to不算),所以要设为slop最少要设为3
        // phraseQuery.add(new Term("content","help"));

        // phraseQuery.add(new Term("content","would"));

        // phraseQuery.setSlop(3);

        // 短语的评分是根据项之间距离越小,评分越高,否则越小
        Hits hits =  searcher.search(phraseQuery);

        printResult(hits);

        searcher.close();
    }

    // 通配符搜索 WildcardQuery
    // 通配符包括’?’匹配一个任意字符和’*’匹配零个或多个任意字符，例如你搜索’use*’，你可能找到’user’或者’uses’：
    public void wildcardSearcher() throws IOException{

            IndexSearcher searcher = new IndexSearcher(directory);

            // 与正则一样,*代表0个或多个字母,?代表0个或一个字母
            // WildcardQuery与QueryParser不同的是:WildcardQuery的前缀可以为*,而QueryParser不行
            WildcardQuery query = new WildcardQuery(new Term("content","a?bbb*"));

            Hits hits = searcher.search(query);

            printResult(hits);

            searcher.close();
    }

    // 模糊搜索 FuzzyQuery
    public void fuzzySearcher() throws IOException{

            IndexSearcher search = new IndexSearcher(directory);

            // OpenOffica虽然没被索引,但能找到相近的OpenOffice
            FuzzyQuery query = new FuzzyQuery(new Term("content","OpenOffica"));

            Hits hits = search.search(query);

            printResult(hits);

            search.close();
    }

    // 使用前缀PrefixQuery
    public void prefixSearcher() throws IOException{

            IndexSearcher search = new IndexSearcher(directory);

            // 全部title前缀为a
            PrefixQuery query = new PrefixQuery(new Term("title","b"));

            Hits hits = search.search(query);

            printResult(hits);

            search.close();

    }

    // 范围搜索 RangeQuery
    public void rangeSearcher() throws IOException{

        IndexSearcher search = new IndexSearcher(directory);

        // RangeQuery query = new RangeQuery(beginTime, endTime, false);
        // 开始时间,结束时间,最后一个参数表示是否包含边界条件本身,如果为false
        RangeQuery query = new RangeQuery(new Term("time","2005"),new Term("time","2007"),true);

        Hits hits = search.search(query);

        printResult(hits);

        search.close();
    }


    // 与或搜索BooleanQuery
    //BooleanClause用于表示布尔查询子句关系的类，包括：BooleanClause.Occur.MUST，BooleanClause.Occur.MUST_NOT，BooleanClause.Occur.SHOULD。有以下6种组合：

    //1．MUST和MUST：取得连个查询子句的交集。

    //2．MUST和MUST_NOT：表示查询结果中不能包含MUST_NOT所对应得查询子句的检索结果。

    //3．MUST_NOT和MUST_NOT：无意义，检索无结果。

    //4．SHOULD与MUST、SHOULD与MUST_NOT：SHOULD与MUST连用时，无意义，结果为MUST子句的检索结果。与MUST_NOT连用时，功能同MUST。

    //5．SHOULD与SHOULD：表示“或”关系，最终检索结果为所有检索子句的并集。

    public void booleanSearcher() throws IOException, ParseException{

        IndexSearcher search = new IndexSearcher(directory);

        QueryParser qp1 = new QueryParser("title",new StandardAnalyzer());

        Query query1 = qp1.parse("aa*");

        QueryParser qp2 = new QueryParser("title",new StandardAnalyzer());

        Query query2 = qp2.parse("bb*");

        BooleanQuery query = new BooleanQuery();

        // 搜索结果的title的前双缀可以是aa,或bb
        query.add(query1, BooleanClause.Occur.SHOULD);

        // BooleanClause.Occur.MUST 必须
        // BooleanClause.Occur.MUST_NOT 必须不是
        query.add(query2, BooleanClause.Occur.SHOULD);

        Hits hits = search.search(query);

        printResult(hits);

        search.close();

    }


    // 多关键的搜索 PhrasePrefixQuery
    public void phrasePrefixSearcher() throws IOException{

        IndexSearcher search = new IndexSearcher(directory);

        PhrasePrefixQuery query = new PhrasePrefixQuery();

        // 这里两项都有可能首先被匹配
        query.add(new Term[]{new Term("content","would"),new Term("content","can")});

        // 只有一项必须匹配
        query.add(new Term("content","help"));

        // If you would like to help promote OpenOffice
        // can I help you
        // slop因子的作用域为查询中的所有短语
        query.setSlop(1);

        // 匹配第一项为 would 或 can 第二项为help
        // solp设置为1
        // If you would like to help promote OpenOffice  除去if to 外,would与help的距离=1
        // can I help you 的距离也=1  所以可以搜索出两条数据

        Hits hits = search.search(query);

        printResult(hits);

        search.close();
    }

    // 在多个域上查询 MultiFieldQueryParser
    public void multiFieldSearcher() throws IOException, ParseException{

        IndexSearcher search = new IndexSearcher(directory);

        // 默认情况下的方式为Occur.SHOULD
        // titile可以匹配bb,content可以匹配you
//      MultiFieldQueryParser.parse(new String[]{"bb","you"},new String[]{"title","content"}, analyzer);

        // titile必须匹配bb,content不能匹配
        Query query = MultiFieldQueryParser.parse( new String[]{"bb","you"},new String[]{"title","content"},new BooleanClause.Occur[]{Occur.MUST,Occur.MUST_NOT}, analyzer);

        // title中必须包含bb  content不能有bb
        // Query query = MultiFieldQueryParser.parse( "bb*",new String[]{"title","content"},new BooleanClause.Occur[]{BooleanClause.Occur.MUST,BooleanClause.Occur.MUST_NOT}, analyzer);

        Hits hits = search.search(query);

        printResult(hits);

        search.close();
    }

    public void printResult(Hits hits) throws IOException{
        for(int i = 0; i < hits.length(); i++){
            Document d = hits.doc(i);
            System.out.println(d.get("title"));
            System.out.println(d.get("content"));
            System.out.println(d.get("time"));
        }
    }


}