Installing HPS Java

Overview

The HPS Java Project is based on the org.lcsim framework and provides a full set of physics reconstruction and simulation tools compatible with the LCIO data format.

Preliminary Tools

Before beginning the installation process, you will want to have available the following tools on your machine first.

Unix

The project itself is cross-platform and should run on Linux, OSX and Windows.  These setup instructions assume a Unix-like environment using the bash shell.  Windows users should be able to execute the equivalent commands on their system to perform the installation successfully.

Java

The software is currently compatible with Java versions 1.7 and greater.  It will not currently build with Java 1.6 or other earlier versions.  You need to download the "Java Platform (JDK)" and not just the JRE.

The bundle for your system should be downloaded from the Java SE downloads site.  Then you need to follow the setup instructions listed there.

You may want to add lines like the following to your shell initialization script, especially if Java is not installed in a standard system location like the /usr directory.

export JAVA_HOME=/path/to/java/jdk
export PATH=$JAVA_HOME/bin:$PATH

This will make sure that the shell can find the Java commands such as java and javac that will be needed for the installation.

Note that there have been problems when using the OpenJDK distribution of java to compile hps-java, therefore make sure that the distribution of java is Oracle's version.

Once the Java installation is completed, you should make sure that the compiler is available from the command line.

[$] javac -version
javac 1.7.0_17

If this command prints "command not found", the current PATH variable probably does not contain the Java bin directory or the location was set incorrectly.

Maven

Maven is a Java based build tool used to create a runnable version of HPS Java on your machine.

You will need to get Maven from the Maven Download Site and save (for instance) the tar.gz file to your machine.

Then you can set it up as follows.

tar -zxvf apache-maven-3.2.3-bin.tar.gz
export MAVEN_HOME=$PWD/apache-maven-3.2.3
export PATH=$MAVEN_HOME/bin:$PATH

Now you should check that the mvn command works.

[$] mvn -version
Apache Maven 3.2.3 [etc.]

If this command does not work, then you should check that the PATH variable is set correctly.

Subversion

Subversion is the source control system system used to obtain the source code from a remote server.  You will need the Subversion client tool in order to checkout the HPS Java code.

Subversion should not be compiled from source code.  It is probably best to either have your local administrator install it if it is not present already, or you can use your package manager (like yum on Redhat systems).

This is an example of using your package manage to do this.

yum install subversion

Windows users can install the TortoiseSVN tool, but its usage is not covered in these instructions.

The Subversion client is a complex command line tool with many sub-commands and options.  You may want to study detailed documentation such as The SVN Book in order to familiarize yourself with it.

Obtaining the Source Code

First, you are going to want to create some kind of work directory so that everything can be kept organized.

mkdir /work/hps
cd /work/hps

You will now use the svn command to checkout the trunk, or main development branch, of the HPS Java Project.

svn checkout svn://svn.freehep.org/hps/java/trunk hps_trunk

This may take awhile as the source code is downloaded from the server.

Building the Project

The Maven tool is used to build all of the modules and produce the jar file used to run command line jobs.

From the hps_trunk directory, you can execute the following command to build the project.

mvn -DskipTests

Especially the first time this is done, it may take quite a long time to bootstrap Maven.

Running the Distribution Jar

The primary tool produced by the installation is a standalone, runnable jar file that can be used along with XML steering files to run reconstruction jobs.

In order to test the installation, you may execute a command such as the following.

java -jar ./distribution/target/hps-distribution-*-bin.jar

The Maven tool will also install this file into your local repository.  This is an example of running the bin jar from your local repository.

java -jar ~/.m2/repository/org/hps/hps-distribution/3.0.3-SNAPSHOT/hps-distribution-3.0.3-SNAPSHOT-bin.jar

The output of these commands will be something like this.

java -jar lcsim-bin.jar [options] steeringFile.xml
usage:
 -D    Define a variable with form [name]=[value]
 -b    Run in headless mode in which plots will not be shown.
 -i    Add an LCIO input file to process
 -n    Set the max number of events to process
 -p    Load a properties file containing variable definitions
 -q    Turn on quiet mode
 -r    Use a steering resource rather than a file
 -s    Set the number of events to skip
 -v    Turn on verbose mode
 -w    Rewrite the XML file with variables resolved
 -x    Perform a dry run which does not process events

Actually running steering files using this tool is covered elsewhere.

Congratulations!  You now have a working local installation of HPS Java.

Using Distributions Jars from Nexus

As an alternative to the above instructions for building the software locally, you may also download and run the distribution jars from a Nexus repository.

This search URL will show all the available versions of the distribution jar that can be downloaded.

Now you can simply click on the "bin jar" link for the distribution version you want to download, save it to your machine, and run it using the previous instructions.