JJack

JJack is a framework for the Java programming language. JJack allows creating and running audio processor clients for the JACK Audio Connection Kit:

- Uses Java to create audio processors (effects processors, synthesizers etc.).
- Provides a JavaBeans-compatible event mechanism to interconnect audio processors.

Native bridge code uses new java.nio.ByteBuffer for direct memory access from Java.

Installation:

Unpack the distribution archive jjack-0_2.tgz to /usr/java. A directory /usr/java/jjack_0-2 will be created. You can also choose a different directory, in that case the absolute path values in the shell-scripts bin/jjack.sh and bin/runBeanBuilder.sh need to be adopted to your choice.

The native bridge library libjjack.so (on Linux systems) needs to be accessible by the Java Virtual Machine (JVM).

There are two ways to make sure the JVM can load the native bridge library:

- Copy the file /lib///* to the system's default library path. On Linux:

cp ./lib/i386/linux/libjjack.so /usr/lib/

Alternatively create a filesystem-link to the binary file at the system's default library location:

cd /usr/lib
ln -s < jjack-install-dir >/lib/i386/linux/libjjack.so

- Or the library-path can directly be set through the JVM system property "java.library.path". Add the parameter "-Djava.library.path=< jjack-install-dir >/lib/i386/linux" to the invocation command.

Note: The current version includes a pre-compiled binary library for i386-Linux. To run JJack on different platforms, the source files libjjack.c and libjjack.h need to be compiled on your system. Please send a copy of the binary and a description of your compilation process if you succeed in running JJack on different platforms.

Before using JJack, don't forget to start the JACK daemon. This is either done by manually invoking jackd, or by configuring the system to start up jackd at boot time. There are several alternative ways to configure and run the daemon, see the JACK user documentation for details (http://www.djcj.org/LAU/jack/).