Hi Daniel, Just saw your email regarding kundera download. Kundera snapshot jar is available at:
http://kundera.googlecode.com/svn/maven2/maven-missing-resources/com/impetus/kundera/1.1.1-SNAPSHOT/ In addition, If you want to download source code then it is at: https://github.com/impetus-opensource/Kundera You could also refer to Kundera-examples for reference at: https://github.com/impetus-opensource/Kundera-Examples I hope it helps. From: Daniel Colchete [mailto:d...@cloud3.tc] Sent: Monday, June 20, 2011 8:23 PM To: user@cassandra.apache.org Subject: Re: Cassandra Clients for Java Thank you all for your answers! It hard to tell the good projects from the not so good projects and it seems that the choice is really between Hector and Pelops. On average, most of the people are using Hector or Pelops and most of the names starts with Da (sorry, couldn't help :)). Dan Washusen asked to comment more regarding Hector's e Pelops' APIs. Lets start with what cassandra gives us: get, insert, remove for simple operations; get_slice to read an entire row (or something like that); multiget_slice and batch_mutate for reading or writing multiple data with a single call. So we could start from this and we would be speaking Cassandra-nease. One CassandraClient class exporting all those methods, with the necessary model classes on the package. All of those methods have small details we don't want to have to work out every time, like timestamp (now is a perfect default value), consistency level (the client could have default values) and string encoding (UTF8 could be a default, but the CassandraClient and the model classes should handle it themselves). So, at this point we would have an API similar to Thrift's but a little less boring to use. With this API we could do failover, load balancing, auto node discovery, and still be speaking Cassandra-nease. But them writing methods to read from Cassandra to create models and to persist models would be a pretty time wasting task. So them we would move to an JPA implementation doing this automagically, like Hector did (thanks for showing this up). The JPA implementation (I have no idea how to write something like this, although I would like to learn), would use our simplified thrift-like interface. In the end: no third semantics, still have direct access to Cassandra to deal with special cases and for most of the cases you have JPA, still have failover and load balancing. How many dependencies do we need besides what Cassandra already requires: zero. Simple, powerful. I agree that I'm not showing a proof-of-concept or anything but it is a good starting vision for a client. Of course there are corner cases and details to work out but, what do you think? With Hector, from their Getting Started page, first you initialize a Cluster, them you create a Keyspace from that cluster, them, wait, you have to create a template for your column family. With that template you can create an updater to do an insert (in Cassandra-nease), or you can query columns to do an get_slice (in Cassandra-nease), or delete column to do a remove (in Cassandra-nease). You can clearly see a third semantics here. With Pelops their documentation on their main website (at GitHub) seems very lacking and I couldn't understand if you have to create a mutator to every write or not and why they assigned strings and not objects to organize connections. They have this pool thing related to the fact that they use strings to organize connections. In the end I think Hector should be a better choice because of their JPA implementation and because Pelops doesn't seem to have documentation. Thanks again for showing the JPA thing up, I really couldn't find anything linking to it. Not even their User guide. Thank you very much for all for the answers. Best, Dani On Sat, Jun 18, 2011 at 4:04 PM, Rajesh Koilpillai <rajesh.koilpil...@gmail.com<mailto:rajesh.koilpil...@gmail.com>> wrote: +1 to Hector (especially with the changes made in the latest version of their API) On Sun, Jun 19, 2011 at 12:01 AM, Steve Willcox <swill...@rallydev.com<mailto:swill...@rallydev.com>> wrote: I'm using Hector. The main contributor Nate McCall is very active and responsive to any issues. The Hector community is very active. I've been using Java for a long time and I disagree that the client is more complex than the underlying Thrift client. The latest version of Hector has made large gains in simplifying the API. It has connection caching, load balancing and failover build into its client. I found it easy to use and stable. My code has been in production since April 2011 and we've not had one Hector issue yet. Hope that helps Steve W. On Fri, Jun 17, 2011 at 4:02 PM, Daniel Colchete <d...@cloud3.tc<mailto:d...@cloud3.tc>> wrote: Good day everyone! I'm getting started with a new project and I'm thinking about using Cassandra because of its distributed quality and because of its performance. I'm using Java on the back-end. There are many many things being said about the Java high level clients for Cassandra on the web. To be frank, I see problems with all of the java clients. For example, Hector and Scale7-pelops have new semantics on them that are neither Java's or Cassandra's, and I don't see much gain from it apart from the fact that it is more complex. Also, I was hoping to go with something that was annotation based so that it wouldn't be necessary to write boilerplate code (again, no gain). Demoiselle Cassandra seems to be one option but I couldn't find a download for it. I'm new to Java in the back-end and I find that maven is too much to learn just because of a client library. Also it seems to be hard to integrate with the other things I use on my project (GWT, GWT-platform, Google Eclipse Plugin). Kundera looks great but besides not having a download link (Google site link to Github, that links to Google site, but no download) its information is partitioned on many blog posts, some of them saying things I couldn't find on its website. One says it uses Lucandra for indexes but that is the only place talking about it, no documentation about using it. It doesn't seem to support Cassandra 0.8 also. Does it? I would like to hear from the users here what worked for you guys. Some real world project in production that was good to write in Java, where the client was stable and is maintained. What are the success stories of using Cassandra with Java. What would you recommend? Thank you very much! Best, -- Dani Cloud3 Tech - http://cloud3.tc/ Twitter: @DaniCloud3 @Cloud3Tech -- Thanks, - Rajesh Koilpillai -- Dani Cloud3 Tech - http://cloud3.tc/ Twitter: @DaniCloud3 @Cloud3Tech ________________________________ Register for Impetus Webinar on 'Leveraging the Cloud for your Product Testing Needs' on June 22 (10:00am PT). Meet Impetus as a sponsor for Hadoop Summit 2011 in Santa Clara, CA on June 29. Click http://www.impetus.com to know more. Follow us on www.twitter.com/impetuscalling NOTE: This message may contain information that is confidential, proprietary, privileged or otherwise protected by law. The message is intended solely for the named addressee. If received in error, please destroy and notify the sender. Any use of this email is prohibited when received in error. Impetus does not represent, warrant and/or guarantee, that the integrity of this communication has been maintained nor that the communication is free of errors, virus, interception or interference.
