12.1.4 Running the M-Let Agent Example

This example is located in the examplesDir/current/MLet/ directory. See “Directories and Classpath” in the Preface for details.

In our example, we have two MBeans representing geometrical shapes. Before running the example, we compile them and create a JAR file for each. We also compile the agent application at the same time.

$ cd examplesDir/current/MLet/
$ javac -classpath classpath *.java

$ jar cf Square.jar Square.class SquareMBean.class
$ rm Square.class SquareMBean.class

$ jar cf EquilateralTriangle.jar EquilateralTriangle.class \
EquilateralTriangleMBean.class
$ rm EquilateralTriangle.class EquilateralTriangleMBean.class

The agent command line requires you to specify first the URL of a JAR file for directly loading the Square class, then the URL of the m-let file. We have left these files in the examples directory, but you could place them on a remote host. With the Korn shell on the Solaris platform, type the following command:

$ java -classpath classpath Agent \ 
file:${PWD}/Square.jar file:${PWD}/GeometricShapes.html

In the output of the agent, you can see it create the m-let loader MBean, and then download classes to create MBeans. It starts with the direct loading of the Square class, and then loads from the HTML file that specifies two EquilateralTriangle MBeans to be loaded. Once these have been loaded, we can see the third one that is loaded through the class loader shortcut.

The agent then starts an HTML adaptor so that we can easily view the new MBeans. In them we can see that the values contained in the ARG tags of the m-let file were used to initialize the MBeans. Point your web browser to the following URL and click on the MBeans in the MLetExample domain:

http://localhost:8082/

When you have finished, press Control-C in the window where you started the agent.