Why mbeans

Find centralized, trusted content and collaborate around the technologies you use most. Connect and share knowledge within a single location that is structured and easy to search. I am trying to understand why MBeans are such a big deal in Java while I don't recall any other language have such paradigm or pattern. So why do the MBeans exist, what problem do they try to solve, and how have the other languages solved that problem?

I would prefer comparisons with Python because I understand that the best. MBeans in java are a way to do management of your application. Say you want to see how long a method takes to execute, or you want to adjust logger settings, or change configuration properties. JConsole comes with the jvm allows you to remotely or locally connect and execute calls on your mbean. There are also a proliferation of tools that use JMX New Relic, and other management tools probably use it.

They are specific to Java, but other languages may have similar counterparts I don't have much knowledge outside of Java unfortunately. MBeans are not a "design pattern". It means nothing outside of JMX. There would be no direct equivalent in other languages unless JMX defined API bindings in other languages, which it doesn't. The reason they exist is because it was prudent for JMX to define a common interface standard for dealing with these objects.

The problem they intend to solve is to give a consistent standardized interface that JMX can work with. In fact, if you are not using JMX, you could argue that even if you called something an "MBean", it conceptually would not be one. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow.

Learn more. Why do Java's MBeans exist? What is the Python equivalent of MBeans? Or do they only exist in Java? Ask Question. Asked 8 years, 3 months ago. Active 8 years, 3 months ago. Viewed 1k times. Improve this question. Gabriel Gabriel 1 1 gold badge 7 7 silver badges 14 14 bronze badges. As defined by the JMX specification, a getter is any public method that does not return void and whose name begins with get.

A getter enables a manager to read the value of the attribute, whose type is that of the returned object. A setter is any public method that takes a single parameter and whose name begins with set. A setter enables a manager to write a new value in the attribute, whose type is the same as that of the parameter.

The straightforward Hello class provides the definitions of the operations and attributes that are declared by HelloMBean. The sayHello and add operations are extremely simple, but real-life operations can be as simple or as sophisticated as needed.

The methods to get the Name attribute and to get and set the CacheSize attribute are also defined. In this example, the Name attribute value never changes. However, in a real scenario this attribute might change as the managed resource runs. For example, the attribute might represent statistics such as uptime or memory usage. Here, the attribute is merely the name Reginald.

Calling the setCacheSize method enables you to alter the CacheSize attribute from its declared default value of In a real scenario, changing the CacheSize attribute could require other operations to be performed, such as discarding entries or allocating new entries. This example merely prints a message to confirm that the cache size has changed.

However, more sophisticated operations could be defined instead of the simple call to println. With the Hello MBean and its interface thus defined, they can now be used to manage the resource they represent, as shown in the following section. Once a resource has been instrumented by MBeans, the management of that resource is performed by a JMX agent. An MBean server is a managed object server in which MBeans are registered. The Main class that follows represents a basic JMX agent:.

ManagementFactory class. The MBeanServer instance obtained by Main is named mbs. Next, Main defines an object name for the MBean instance that it will create. Namely, the object name must contain a domain and a list of key-properties.

In the object name defined by Main , the domain is com. In addition, the key-property declares that this object is of the type Hello.

An instance of a Hello object, named mbean , is created.