example lucene query parsers

import groovy.grape.Grape

Grape.addResolver(name:'mvnRepository', root:'http://central.maven.org/maven2/')
Grape.addResolver(name:'kint', root:'http://nexus.k-int.com/content/repositories/releases')
Grape.grab(group:'org.apache.lucene', module:'lucene-queryparser', version:'8.4.0')


import org.apache.lucene.search.Query;
import org.apache.lucene.queryparser.classic.QueryParser;

private void interpret(Query q, int depth) {
  println("${q} - ${q.class.name}");
  switch ( q.class ) {
    case org.apache.lucene.search.TermQuery:
      println("TermQuery");
      break;
    case org.apache.lucene.search.BooleanQuery:
      println("Boolean ${q}");
      q.clauses.each { clause ->
        interpret(clause.getQuery(), depth+1);
      }
      break;
    default:
      println("Unhandled: ${q.class.name}");
      break;
  }
}

def queries = [
  'title:fred',
  'title:"fred phrase search"',
  'title:fred author:freda',
  'title:fred ( author:freda AND author:jane )'
]


org.apache.lucene.analysis.standard.StandardAnalyzer analyzer = new org.apache.lucene.analysis.standard.StandardAnalyzer();
queries.each { qrystr ->
  println("Parse ${qrystr}");
  Query q = new QueryParser("title", analyzer).parse(qrystr);
  println("Parsed into ${q}");
  interpret(q,0);
}