Lucene--FuzzyQuery与WildCardQuery(通配符)

时间:2023-03-08 22:03:35

FuzzyQuery:

创建索引:

IndexWriter writer = new IndexWriter(path, new StandardAnalyzer(), false); 

writer.setUseCompoundFile(false);

Document doc1 = new Document(); 

Document doc2 = new Document(); 

Document doc3 = new Document(); 

Document doc4 = new Document(); 

Document doc5 = new Document(); 

Document doc6 = new Document();

Field f1 = new Field("content", "word", Field.Store.YES,
Field.Index.TOKENIZED); Field f2 = new Field("content", "work", Field.Store.YES,
Field.Index.TOKENIZED); Field f3 = new Field("content", "seed", Field.Store.YES,
Field.Index.TOKENIZED); Field f4 = new Field("content", "sword", Field.Store.YES,
Field.Index.TOKENIZED); Field f5 = new Field("content", "world", Field.Store.YES,
Field.Index.TOKENIZED); Field f6 = new Field("content", "ford", Field.Store.YES,
Field.Index.TOKENIZED); doc1.add(f1);
doc2.add(f2);
doc3.add(f3);
doc4.add(f4);
doc5.add(f5);
doc6.add(f6); writer.addDocument(doc1);
writer.addDocument(doc2);
writer.addDocument(doc3);
writer.addDocument(doc4);
writer.addDocument(doc5);
writer.addDocument(doc6); writer.close();

  

注:IndexWriter中的create的变量值一般设为true

搜索:

IndexSearcher searcher = new IndexSearcher(path);
//构建一个Term,然后对其进行模糊查找 Term t = new Term("content", "work"); FuzzyQuery query = new FuzzyQuery(t);
//FuzzyQuery还有两个构造函数,来限制模糊匹配的程度
// 在FuzzyQuery中,默认的匹配度是0.5,当这个值越小时,通过模糊查找出的文档的匹配程度就
// 越低,查出的文档量就越多,反之亦然 FuzzyQuery query1 = new FuzzyQuery(t, 0.1f); FuzzyQuery query2 = new FuzzyQuery(t, 0.1f, 1);
Hits hits = searcher.search(query2); for (int i = 0; i < hits.length(); i++) { System.out.println(hits.doc(i));
}
searcher.close();

  

模糊搜索的三种构造函数,具体讲一下参数的用法(以第三个为例);

第一个参数当然是词条对象,第二个参数指的是levenshtein算法的最小相似度,第三个参数指的是要有多少个前缀字母完全匹配:

WildCardQuery:

通配符就更简单了,只要知道“*”表示0到多个字符,而使用“?”表示一个字符就行了:

IndexSearcher searcher=new IndexSearcher(path);

Term t1=new Term("content","?o*");

WildcardQuery query=new WildcardQuery(t1);
Hits hits=searcher.search(query); for(int i=0;i<hits.length();i++)
{ System.out.println(hits.doc(i));
}

  

That“s all!