Datastax Java Driver for Apache Cassandra

If you're reading this on GitHub, please note that this is the readme for the development version and that some features described here might not yet have been released. You can find the documentation for latest version through Java driver docs or via the release tags, e.g. 2.1.5.

A Java client driver for Apache Cassandra. This driver works exclusively with the Cassandra Query Language version 3 (CQL3) and Cassandra's binary protocol.

JIRA: https://datastax-oss.atlassian.net/browse/JAVA
MAILING LIST: https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user
IRC: #datastax-drivers on irc.freenode.net
TWITTER: Follow the latest news about DataStax Drivers - @olim7t, @mfiguiere
DOCS: http://www.datastax.com/documentation/developer/java-driver/2.1/index.html
API: http://www.datastax.com/drivers/java/2.1
CHANGELOG: https://github.com/datastax/java-driver/blob/2.1/driver-core/CHANGELOG.rst

The driver architecture is based on layers. At the bottom lies the driver core. This core handles everything related to the connections to a Cassandra cluster (for example, connection pool, discovering new nodes, etc.) and exposes a simple, relatively low-level API on top of which higher level layer can be built.

The driver contains the following modules:

driver-core: the core layer.
driver-mapping: the object mapper.
driver-examples: example applications using the other modules which are only meant for demonstration purposes.

Please refer to the README of each module for more information.

Maven

The last release of the driver is available on Maven Central. You can install it in your application using the following Maven dependency:

<dependency>
  <groupId>com.datastax.cassandra</groupId>
  <artifactId>cassandra-driver-core</artifactId>
  <version>2.1.5</version>
</dependency>

Note that the object mapper is published as a separate artifact:

<dependency>
  <groupId>com.datastax.cassandra</groupId>
  <artifactId>cassandra-driver-mapping</artifactId>
  <version>2.1.5</version>
</dependency>

We also provide a shaded JAR to avoid the explicit dependency to Netty.

Compatibility

The Java client driver 2.1 (branch 2.1) is compatible with Apache Cassandra 1.2, 2.0 and 2.1.

UDT and tuple support is available only when using Apache Cassandra 2.1 (see CQL improvements in Cassandra 2.1).

Other features are available only when using Apache Cassandra 2.0 or higher (e.g. result set paging, BatchStatement, lightweight transactions -- see What's new in Cassandra 2.0). Trying to use these with a cluster running Cassandra 1.2 will result in an UnsupportedFeatureException being thrown.

Upgrading from previous versions

If you are upgrading from the 2.0.x branch of the driver, be sure to have a look at the upgrade guide.

If you are upgrading from the 1.x branch, follow the upgrade guide to 2.0, and then the above document.

Troubleshooting

If you are having issues connecting to the cluster (seeing NoHostAvailableConnection exceptions) please check the connection requirements.

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0