The Java Management Extensions (JMX) API

The JMX API is a standard API for management and monitoring of resources such as applications, devices, services, and the Java virtual machine.
Typical uses of the JMX technology include:

• Consulting and changing application configuration.
• Accumulating and publishing statistics about application behavior.
• Notifying users or applications of state changes and erroneous conditions.

The JMX API includes remote access, so a remote management program can interact with a running application for the above purposes.

see :
http://openjdk.java.net/groups/jmx/
http://en.wikipedia.org/wiki/Java_Management_Extensions