title: How to use MultiFieldQueryParser from Lucene?
body: <p>I am using <code>Version.Lucene_29</code>. Using the normal string query method i could do the following:</p>
  
  <pre><code>Directory directory = new FSDirectory(...);
  //Start Lucene retrieval.
  IndexSearcher iSearch = new IndexSearcher(directory, true);
  Analyzer analyzer = new WhitespaceAnalyzer();
  QueryParser parser = new QueryParser(Version.LUCENE_29, "content", analyzer);
  String str = 'filename:testfile.txt AND filetext:"Singapore food"'
  Query query = parser.parse(str);
  ScoreDoc[] hits = iSearch.search(query, 1000).scoreDocs;
  </code></pre>
  
  <p>How do i fire a query using MultiFieldQueryParser in Lucene similar to the string query method?</p>
  
  <pre><code>MultiFieldQueryParser multiParser = new MultiFieldQueryParser(
      Version.LUCENE_29, new String[] {"content", "ne"}, analyzer);
  str = ???
  Query = ????
  ScoreDoc[] hits = iSearch.search(query, 1000).scoreDocs;
  </code></pre>