You need JAVA: JRE 1.6 at least (1.8 recommended). You can download it from [java.com|http://www.java.com/download/]
Start rapla.bat (rapla.sh under Unix). If the .jar extension is associated to your Java Runtime Enviroment you can also double-click on the rapla.jar (rapla.jar is located in the lib subfolder of your binary-distribution)
You can also start Rapla by directly calling the java command. Change into the rapla-directory and type:
java -jar lib/common/rapla.jar
To start Rapla from the command-line, you have to set the java command in your PATH-Variable (if its not already there) Example:
setenv PATH $PATH:/usr/local/java/bin
This error happens when there is many events (data.xml > 900Ko). Before starting RAPLA, indicate a bigger maximum heap size. In the examples it is set to 500Mb:
setenv JAVA_OPTIONS "-Xmx500M"