title: How to make a bidirectional one-to-one relation by GreenDAO?
body: <p>I use ORM GreenDAO for DAL layer of my Android app. I've a problem in one to one relation between two tables. for example:</p>
  
  <pre><code>Entity page = schema.addEntity("Page");
  Entity bookmark = schema.addEntity("Bookmark");
  
  Property pageIdProperty = bookmark.addLongProperty("pageId").getProperty();
  
  bookmark.addToOne(page, pageIdProperty); // any bookmark related to a page
  page.addToOne(bookmark, pageIdProperty); // any page can has a bookmark
  </code></pre>
  
  <p>Is this relation mistake?</p>
  
  <p>When I define it, I can't call <code>page.getBookmark()</code> in the <strong>Page Class</strong></p>
  
  <p>If this is true, Does any way I can make it bidirectional for one to one relationship?</p>