The form that an mxj~ object takes -- the number of inlets, outlets and the messages it understands -- is determined by the Java class that it instantiates. Unlike the Max mxj object, the mxj~ object is able to perform operations on signal vectors in an MSP processing chain. Using mxj~ requires that the host computer have a recent version of the Java Virtual Machine (JVM) installed. Macintosh users can ensure that they have the most up-to-date version of the JVM by running Software Update from the System Preferences. By default, Windows XP does not have a version of the JVM installed. As of the writing of this document the most recent version of the JVM can be downloaded from this
Max includes a directory called "java-doc", which can be found on Windows machines at
C:\Program Files\Common Files\Cycling '74\java-doc
and on Macintosh machines at
The following important subdirectories are in the java-doc directory:
"classes" - contains the source code and class files of the example Java classes that are included with Max.
"help" - contains the help files that are associated with the example Java classes. Exploring these patches is a good, quick way to see how mxj~ has extended and will extend the Max universe.
"doc/tutorial" - contains a step-by-step tutorial that leads you through the process of creating your first Java class to the application of advanced mxj~ programming techniques. The tutorial is in HTML format.
"doc/api" - contains html files that specify mxj~ 's Application Programming Interface (API). These pages will serve as an invaluable resource when you are coding your own Java classes.
"doc/ide" - contains example projects for some of the Integrated Development Environments (IDEs) we think you may want to use to create Java classes.
"doc/mxj~ examples" - contains example classes for signal processing
"lib" - contains the code libraries that the mxj~ object uses to bridge the worlds of Max and Java.
In addition, a file named "max.java.config.txt" is also located in the java directory. This file allows you to specify which diretories should be in Java's classpath - a concept roughly analogous to the Max search path.
The mxj~ object must be given the name of a valid Java class as the first argument. The Java class file must exist somewhere within the classpath, and it must be a class that was designed for use with the mxj~ object (the class must subclass com.cycling74.max.MaxObject). The number of inlets that an instance of mxj~ creates and the messages that it will respond to are determined by declarations made in the peer Java class.
The mxj~ object supports the definition of attributes within the Java code for a peer class. The attributes that are settable at the time of instantiation using the @ paradigm. For instance, if a particular class Foo defined an integer attribute called intBar, one could create an instance of the class with the attribute set to the value 74 by typing in an object box.
Common Box Attributes
The number of outlets that an instance of mxj~ creates is determined by declarations made in the constructor of the peer Java class. The furthest outlet to the right may or may not be an info outlet whose sole responsibility is to report information about the attributes when queried.