Monitors Inside the Monitoring Tree
Definition
The monitoring infrastructure builds a tree of monitors (a monitoring tree). Each monitor presents an agent that communicates with a particular monitored resource and processes the collected data. A monitor represents a small amount of data. It contains a simple type value that gives information about a single aspect of a monitored object.
Use
A monitor can represent the name of an object or the number of successful transactions with an object, but not the object itself. That is why a resource that works with several objects and wants to provide information about them in the monitoring infrastructure has to define several monitors representing different aspects of each object and must then group them semantically so that the group represents the whole object.
Structure
The monitor is always part of a group of monitors describing an object. The objects themselves can be logically grouped further inside the monitoring tree in summaries. The summaries can be grouped together with other summaries; objects in summaries again, and so on.
Thus, the hierarchical structure of the monitoring tree follows the semantics of the objects being monitored. In the monitoring tree, the leaves are always monitors, the nodes in the first level above the leaves are objects, and the nodes in the upper levels are summaries.
The summaries from the first level below the root are predefined. They are named Kernel, Services, Applications, System, and Performance. These predefined summaries denote different problematic areas that can be monitored inside the AS Java.
The monitoring infrastructure supports the following types of monitors: text, state, table, version, configuration, availability, integer, long, frequency, quality and duration monitors. For more information, see Types of Monitors and Their Usage .
Example
The graphic below gives an idea what the monitoring tree looks like in the Monitor Browser .
