JMX (Java Management Extensions)

The JMX Device Driver allows Iotellect Server to communicate with Java-based applications and Application Servers using Java Management Extensions (JMX) protocol. Functionality provided by the driver:

• Discovery of MBeans provided by an MBean Server (JMX host).
• Creation of a Device context setting per every available MBean attribute.
• Creation of a Device context operation per every operation provided by MBean.
• Creation of a Device context event definition per every notification type provided by MBean.
• Execution of MBean queries.

MBean queries allow selecting multiple MBeans of the equal format/type. Each query results to a table that lists all properties of selected MBeans in its columns, one MBean instance per row.

An query text consists of two parts, the domain and the key properties, separated by the colon character (:).

The domain is a string of characters not including the colon (:). It may include occurrences of the wildcard characters asterisk (*) or question mark (?). The asterisk matches any sequence of zero or more characters, while the question mark matches any single character. If the domain is empty, it will be replaced in certain cases by the default domain of the MBean server.

The key properties are an unordered comma-separated set of keys and associated values. Each key is a nonempty string of characters which may not contain any of the characters comma (,), equals (=), colon, asterisk, or question mark. The same key may not occur twice in a given query.

The key properties list may contain a single asterisk element (*) which means that MBeans selected by the query may contain any number of other (unspecified) properties.

Example: java.lang:type=GarbageCollector,* This MBean query lists all MBeans in java.lang domain that have type property those value equals to GarbageCollector. Those MBeans may have any number of other properties with any values.

Each value associated with a key is a string of characters that is either unquoted or quoted.

• An unquoted value is a possibly empty string of characters which may not contain any of the characters comma, equals, colon, quote, asterisk, or question mark.
• A quoted value consists of a quote ("), followed by a possibly empty string of characters, followed by another quote. Within the string of characters, the backslash () has a special meaning. It must be followed by one of the following characters:
  • Another backslash. The second backslash has no special meaning and the two characters represent a single backslash.
  • The character 'n'. The two characters represent a newline ('n').
  • A quote. The two characters represent a quote, and that quote is not considered to terminate the quoted value. An ending closing quote must be present for the quoted value to be valid.
  • A question mark (?) or star (*). The two characters represent a question mark or star respectively.

Some other MBean query examples: *:type=Foo,name=Bar to match names in any domain whose exact set of keys is type=Foo,name=Bar. d:type=Foo,name=Bar,* to match names in the domain d that have the keys type=Foo,name=Bar plus zero or more other keys. *:type=Foo,name=Bar,* to match names in any domain that has the keys type=Foo,name=Bar plus zero or more other keys. d:type=F?o,name=Bar will match e.g. d:type=Foo,name=Bar and d:type=Fro,name=Bar. d:type=F*o,name=Bar will match e.g. d:type=Fo,name=Bar and d:type=Frodo,name=Bar. d:type=Foo,name="B*" will match e.g. d:type=Foo,name="Bling". Wildcards are recognized even inside quotes, and like other special characters can be escaped with .

A quote, question mark, or star may not appear inside a quoted value except immediately after an odd number of consecutive backslashes.

Spaces have no special significance in an MBean query. For example, the string domain: key1 = value1 , key2 = value2 represents an query with two keys. The name of each key contains six characters, of which the first and last are spaces. The value associated with the key " key1 " also begins and ends with a space.

No part of a query may contain a newline character ('n'), whether the domain, a key, or a value, whether quoted or unquoted. The newline character can be represented in a quoted value with the sequence n.

None defined.

None defined.

Connection properties define how Iotellect Server communicates with a JMX server. These settings may be accessed using the Edit Device Properties action of Device Context. The following connection properties are available:

This property contains a table of MBean queries:

The driver creates one root asset for every MBean instance provided by the MBean server.

The list of MBeans available on a JMX host may change at any time. To force the server re-reading list of MBeans (assets) on every synchronization, switch Metadata Reading Mode setting of a JMX device account to Read all.

JMX device driver creates one Device setting variable per every attribute of every discovered MBean. These variables are grouped by MBean names and/or descriptions to facilitate navigation.

Additionally, one setting variable is created per every query defined in MBean Queries table. This tabular variable lists properties of MBeans selected by the query.

JMX device driver creates one Device context function and action per every operation provided by every discovered MBean. These actions are grouped by MBean names and/or descriptions to facilitate navigation.

JMX device driver creates one Device context event definition per every notification type of every discovered MBean. The driver automatically adds a notification listener for every notification and generates a Iotellect Server event when a notification is received.

This driver makes the device Online if:

• TCP connection to a JMX host was successfully established
• JMX RMI connector authentication and authorization did not fail

Synchronization between Iotellect Server and JMX host includes the following steps:

• Reading a list of available MBeans.
• Reading information about attributes provided by every MBean.
• Reading information about operation provided by every MBean.
• Reading information about notifications provided by every MBean.
• Reading/writing values of all attributes.
• Executing all MBean queries and reading attributes of all MBeans matching those queries.
• Subscribing to the notifications.

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