The tutorial doesn't cover all of the sample applications found in the examples directory. All of the examples include detailed README files and well-commented code. In addition, certain topics can be found elsewhere:
The MBean registration process is covered in the JMX agent specification.
Proxy MBeans are introduced in Getting Started with the Java Dynamic Management Kit 4.0.
The heartbeat mechanism in protocol connectors is covered in the Javadoc for the RmiConnectorClient class and demonstrated in the HeartBeat example.
The secure HTTP connector and the secure class loading in the m-let service are covered in their respective Javadoc pages. These components also rely on the Java Secure Socket Extension 1.0 API and the javakey tool, respectively, which are documented on Sun's Java technology web site (http://java.sun.com).
The monitoring and timer services are covered in the JMX specification.