title: How to read a document in lucene which is not stored but indexed
body: <p>Hello i have  3 fields title,content,url and i created the index added some document</p>
  
  <pre><code> Document doc = new Document();
    doc.add(new TextField("title", title, Field.Store.YES));
    doc.add(new TextField("content", title, Field.Store.YES));
    doc.add(new StringField("url", isbn, Field.Store.NO));
    w.addDocument(doc);
  </code></pre>
  
  <p>I can read the index using the index writer and iterate and receive the field title,content how can i receive the field url ?</p>