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The JMX Stands for Java Management Extensions technology is a standard part of the Java Platform, Standard Edition (Java SE platform). The JMX technology was added to the platform in the Java 2 Platform, Standard Edition (J2SE) 5.0 release.

The JMX technology provides a simple, standard way of managing resources such as applications, devices, and services. Because the JMX technology is dynamic, you can use it to monitor and manage resources as they are created, installed and implemented. You can also use the JMX technology to monitor and manage the Java Virtual Machine (Java VM). The JMX specification defines the architecture, design patterns, APIs, and services in the Java programming language for management and monitoring of applications and networks.

Using the JMX technology, a given resource is instrumented by one or more Java objects known as Managed Beans, or MBeans. These MBeans are registered in a core-managed object server, known as an MBean server. The MBean server acts as a management agent and can run on most devices that have been enabled for the Java programming language.

The JMX technology defines standard connectors (JMX connectors) that enable you to access JMX agents from remote management applications. JMX connectors using different protocols provide the same management interface.

The JMX technology provides several advantages are as given below:

1. The JMX technology enables Java applications to be managed without heavy investment. A JMX technology-based agent (JMX agent) can run on most Java technology-enabled devices. Consequently, Java applications can become manageable with little impact on their design.
2. The JMX technology provides a standard way to manage Java applications, systems, and networks. For example, the Java Platform, Enterprise Edition (Java EE) 5 Application Server conforms to the JMX architecture and consequently can be managed by using JMX technology.
3. The JMX technology can be used for out-of-the-box management of the Java VM. The Java Virtual Machine (Java VM) is highly instrumented using the JMX technology. You can start a JMX agent to access the built-in Java VM instrumentation, and thereby monitor and manage a Java VM remotely.
4. The JMX technology provides a scalable, dynamic management architecture. Every JMX agent service is an independent module that can be plugged into the management agent, depending on the requirements. The JMX specification provides a set of core agent services. Additional services can be developed and dynamically loaded, unloaded, or updated in the management infrastructure.
5. The JMX technology leverages existing standard Java technologies. Whenever needed, the JMX specification references existing Java specifications, for example, the Java Naming and Directory Interfaces API.
6. The JMX technology-based applications (JMX applications) can be created from a NetBeans IDE module. You can obtain a module from the NetBeans Update Center (select Tools -> Update Center in the NetBeans interface) that enables you to create JMX applications by using the NetBeans IDE. This reduces the cost of development of JMX applications.
7. The JMX technology integrates with existing management solutions and emerging technologies. The JMX APIs are open interfaces that any management system vendor can implement. JMX solutions can use lookup and discovery services and protocols such as Jini network technology and the Service Location Protocol (SLP).

The JMX technology can be divided into three parts, as follows:

1. Instrumentation
2. JMX Agent
3. Remote Management

1. Instrumentation: Using the JMX technology, you must first instrument the resources in the Java programming language. You use Java objects known as MBeans to implement the access to the resources' instrumentation.

MBeans must follow the design patterns and interfaces defined in the JMX specification. Doing so ensures that all MBeans provide managed resource instrumentation in a standardized way. In addition to standard MBeans, the JMX specification also defines a special type of MBean called an MXBean.

An MXBean is an MBean that references only a pre-defined set of data types. Other types of MBean exist, but this trail will concentrate on standard MBeans and MXBeans. Once a resource has been instrumented by MBeans, it can be managed through a JMX agent. MBeans do not require knowledge of the JMX agent with which they will operate.

2. JMX Agent: A JMX technology-based agent (JMX agent) is a standard management agent that directly controls resources and makes them available to remote management applications. JMX agents are usually located on the same machine as the resources they control, but this arrangement is not a requirement.

The core component of a JMX agent is the MBean server, a managed object server in which MBeans are registered. A JMX agent also includes a set of services to manage MBeans, and at least one communications adaptor or connector to allow access by a management application.

3. Remote Management: JMX technology instrumentation can be accessed in many different ways, either through existing management protocols such as the Simple Network Management Protocol (SNMP) or through proprietary protocols. The MBean server relies on protocol adaptors and connectors to make a JMX agent accessible from management applications outside the agent's Java Virtual Machine (Java VM).

Each adaptor provides a view through a specific protocol of all MBeans that are registered in the MBean server. For example, an HTML adaptor could display an MBean in a browser.

The JMX Technology support in Spring provides us with the features to easily and transparently integrate your Spring application into a JMX infrastructure. Specifically, Spring’s JMX support provides four core features:

1. The automatic registration of any Spring bean as a JMX MBean.
2. A flexible mechanism for controlling the management interface of your beans.
3. The declarative exposure of MBeans over remote, JSR-160 connectors.
4. The simple proxying of both local and remote MBean resources.

These features are designed to work without coupling your application components to either Spring or JMX interfaces and classes.