title: How to store java objects on Solr
body: <p>I want to store java objects as part of the Solr document.
  They don't need to be parsed or searched, only be returned as part of the document.
  I can convert them to json or XML and store the text but I prefer something more efficient.
  If I could use Java serialization and then add the binary blob to the document it could be ideal.
  I'm aware of the option to convert the binary blob with base64 but I was wondering if there is a more efficient way.</p>