As Drools is an open source project, instructions for building from source are part of the manual ! Building from source means you can stay on top with the latest features. Whilst aspects of Drools are quite complicated, many users have found ways to become contributors.
Drools works with JDK1.4 and above. you will need also need to have the following tools installed. Minimum requirement version numbers provided.
Ensure the executeables for ant and java are in your path. The examples given illustrative and are for a win32 system:
Path=D:\java\j2sdk1.4.2_10\bin;D:\java\apache-ant-1.6.5\bin;
Following environment variables will also need to be set. The examples given illustrative and are for a win32 system::
JAVA_HOME=D:\java\j2sdk1.4.2_10
ANT_HOME=D:\java\apache-ant-1.6.5
Past releases used to use maven 2 as the build mechanism, but now ant is used as the primary mechanism. Maven is used underneath the covers as the mechanism for managing project dependencies etc. (You can of course still have maven 2 installed and use it if needed - there is a pom.xml structure for each module - this is what is used for dependency management).