Java Management Extensions

This section describes how to use Java Management Extensions (JMX), which are a set of Java administrative APIs used to customize WebSphere Application Server - Express administration. WebSphere Application Server - Express supports access to the administrative functions through a set of Java classes and methods. You can write a Java program that performs any of the administrative features of the WebSphere Application Server - Express administrative tools. You can also extend basic WebSphere Application Server - Express administration to include your own managed resources.

You can connect to a running server or perform some tasks on configuration files directly with the JMX APIs. To use JMX APIs when the server is not running, specify AdminClient.CONNECTOR_TYPE_NONE. This mode modifies the configuration files directly. When you use this mode to change the configuration, you must ensure that the proper authorities are set up for any objects that you create. When you use other connector types to connect to a running application server or deployment manager, the proper authorities are configured automatically.

It is recommended that you follow these guidelines when using CONNECTOR_TYPE_NONE for any files that are created. Files created are usually located in the instance_name/config and instance_name/installedApps directories:

• Make the QEJBSVR profile the owner of any objects that are created, including objects in the instance_name/config and instance_name/installedApps directories.

• The QEJBSVR profile must have *RWX authority on the directories and *RW authority on the files.

• *PUBLIC should be *EXCLUDE on any files or directories. This can be set by running the JMX program with these Java properties:
  • os400.file.create.auth=none
  • os400.dir.create.auth=none

When you develop and run administrative clients that use various JMX connectors and that have security enabled, use the following guidelines. When you follow these guidelines, you guarantee the behavior among different implementations of JMX connectors. Any programming model that does not follow these guidelines is unsupported.

• Create and use a single administrative client before you create and use another administrative client.

• Create and use an administrative client on the same thread.

• Use one of the following ways to specify a user ID and password to create a new administrative client:
  • Specify a default user ID and password in the property file.
  • Specify a user ID and password other than the default. After you create an administrative client with a non-default user ID and password, specify the same non-default user ID and password when you create subsequent administrative clients.

These topics provide an overview of how you can use JMX with WebSphere Application Server - Express:

Customize with JMX
This topic describes how to manage your WebSphere Application Server - Express environment and deploy applications with Java administrative APIs.

Customize using JMX MBeans
This topic describes how to extend WebSphere Application Server - Express administration with JMX MBeans.

Example: J2EE security permissions
This example gives you the parameters necessary to grant J2EE security permissions in order to call JMX methods.

For more information, see these resources:

• JMX Javadoc
• Java Management Extensions (JMX)
• System Administration for WebSphere Application Server V5 -- Part 2: Writing Your Own Administration Programs