Implementation of the xrootd data access protocol in Java. The project provides a library for integration and a standalone xrootd data server.
xrootd is the native data access protocol of the ROOT data analysis framework. The reference implementation of the protocol is provided by SLAC National Accelerator Laboratory.
dCache is a distributed storage system frequently used in the Worldwide LHC Computing Grid, high energy physics, photon sciences, and other communities.
This project provides our implementation of the xrootd data access protocol in Java. The library is used to implement the xrootd support in dCache.
A standalone data server is provided. The primary purpose of the standalone data server is for testing, both interoperability testing and as a platform to test plugins without having to install dCache.
xrootd4j heavily depends on Netty, a high performance asynchronous event-drive network application framework.
To compile the project simply execute:
mvn package
To install the core library (xrootd4j) into your local maven repository run:
mvn -am -pl xrootd4j install
Add the following Maven dependency to your project:
<dependency>
<groupId>org.dcache</groupId>
<artifactId>xrootd4j</artifactId>
<version>2.0.0</version>
</dependency>
To automatically download the dependency, add our Maven repository to your project:
<repositories>
<repository>
<id>xrootd4j.repository</id>
<url>https://download.dcache.org/nexus/content/repositories/releases/</url>
</repository>
</repositories>
Alternatively, download or build the JAR by hand and add it to the build classpath.
The standalone server may be executed as follows:
java -Dlog=debug -jar xrootd-standalone/target/xrootd4j-standalone-2.0.0-jar-with-dependencies.jar
Please adjust the log level as needed. Add the -h option at the end of the command to get a brief synopsis of available options.
The code was originally written by Martin Radicke and sponsored by DESY. It has since been maintained by Gerd Behrmann and Thomas Zangerl sponsored by NDGF.