无法取消对java QueryParser short的引用

Question

我有一些索引文档，我想用一个查询来搜索它们，我检查了lucene文档并编写了这段代码，但不知怎的，我在QueryParser行中得到了“short Can Dereference”，我是Java和lucene的新手，我使用lucene 5.3.1

import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import static java.time.Clock.system;
import javax.management.Query;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.core.KeywordAnalyzer;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.FuzzyQuery;
import org.apache.lucene.search.IndexSearcher;

import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import static sun.rmi.transport.TransportConstants.Version;
import static sun.rmi.transport.TransportConstants.Version;




public class Searcher
{
    public static void main(String args[]) throws IOException{
        String  query="computer science";
        Analyzer analyzer = new KeywordAnalyzer();
         Query q = new QueryParser(Version.LUCENE_CURRENT, "W", analyzer).parse(query); //ERROR IS HERE

         Path indexPath = Paths.get("MonIndex");
        Directory directory = FSDirectory.open(indexPath);
        DirectoryReader reader = DirectoryReader.open(directory);
        IndexSearcher iSearcher = new IndexSearcher(reader);

        TopDocs topdocs = iSearcher.search(q2, 100);
        ScoreDoc[] resultsList = topdocs.scoreDocs;
         for(int i = 0; i<resultsList.length; i++){
             Document book = iSearcher.doc(resultsList[i].doc); 
             System.out.println(book.getField("I").stringValue());
         }

    }

}

Answer 1

问题是Version.LUCENE_CURRENT。您没有导入Lucene的Version，但是您确实有sun.rmi.transport.TransportConstants.Version，虽然我不熟悉这个库，但它肯定是does appear to be a short。因此，试图通过引用不存在的sun.rmi.transport.TransportConstants.Version.LUCENE_CURRENT来取消引用，会导致抛出该错误

但是，在您所说的Lucene版本中，the ^{}ctor甚至不再接受版本参数，所以只需删除它：

Query q = new QueryParser("W", analyzer).parse(query);

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您的下一个错误：queryparser返回的Query不是javax.management.Query