Create and registering standard, dynamic, and open custom MBeans

We can create standard, dynamic, and open custom MBeans and register them with the WAS administrative service.

 

Before you begin

This task assumes a basic familiarity with MBean programming. For information on MBean programming see MBean Java application programming interface (API) documentation.

 

Overview

Perform the following tasks to create and register a standard, dynamic, or open custom MBean.

 

Procedure

1. Create your particular MBean class or classes.

2. Write an MBean descriptor in the XML language for your MBean.

3. Register your MBean by inserting code that uses the WebSphere Application Server run-time com.ibm.websphere.management.UserMBeanCollaborator collaborator class into your application code.

4. Package the class files for your MBean interface and implementation, the descriptor XML file, and your application JAR file.

 

Result

After you successfully complete the steps, you have a standard, dynamic, or open custom MBean that is registered and activated with the WebSphere Application Server administrative service.

 

Example

The following example shows how to create and register a standard MBean with the WAS administrative service:

SnoopMBean.java:

/**
 * Use the SnoopMBean MBean, which has a standard mbean interface.
 */ 
public interface SnoopMBean {
    public String getIdentification();
    public void snoopy(String parm1);
}

SnoopMBeanImpl.java:

/**
 * SnoopMBeanImpl - SnoopMBean implementation
 */ 
public class SnoopMBeanImpl implements SnoopMBean {
    public String getIdentification() {
        System.out.println(">>> getIdentification() called...");
        return "snoopy!";
    }
    
    public void snoopy(String parm1) {
        System.out.println(">>> snoopy(" + parm1 + ") called...");
    }
}

SnoopMBean.xml:


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE MBean SYSTEM "MbeanDescriptor.dtd">
<MBean type="SnoopMBean"
 version="5.0"
 platform="dynamicproxy"
 description="Sample SnoopMBean to be initialized inside an EJB.">


 <attribute name="identification" getMethod="getIdentification" type="java.lang.String" proxyInvokeType="unicall"/>

 <operation name="snoopy" role="operation"  type="void" targetObjectType="objectReference" 
   impact="ACTION" proxyInvokeType="multicall">
  <signature>
   <parameter name="parm1" description="test parameter" type="java.lang.String"/>
  </signature>
 </operation>
</MBean>

//The method MBeanFactory.activateMBean() requires four parameters:
//String type: The type value that you put in this MBean's descriptor. For this example 
//the string type is SnoopMBean.
//RuntimeCollaborator co: The UserMBeanCollaborator user MBean collaborator instance 
//that you create
//String id: Unique name that you pick
//String desciptor: The MBean descriptor file name


import com.ibm.websphere.management.UserMBeanCollaborator;
//Import other classes here.
.
.
.
static private ObjectName snoopyON = null;
static private Object lockObj = "this is a lock";
.
.
.
/**
 * ejbCreate method: Register your Mbean.
 */
public void ejbCreate() throws javax.ejb.CreateException {
    synchronized (lockObj) {
        System.out.println(">>> SnoopMBean activating for --|" + this + "|--");
        if (snoopyON != null) {
            return;
        }
        try {
            System.out.println(">>> SnoopMBean activating...");
            MBeanFactory mbfactory = AdminServiceFactory.getMBeanFactory();
            RuntimeCollaborator snoop = new UserMBeanCollaborator(new SnoopMBeanImpl());
            snoopyON = mbfactory.activateMBean("SnoopMBean", snoop, "snoopMBeanId", "SnoopMBean.xml");
            System.out.println(">>> SnoopMBean activation COMPLETED! --|" + snoopyON + "|--");
        } catch (Exception e) {
            System.out.println(">>> SnoopMBean activation FAILED:");
            e.printStackTrace();
        }
    }
}
.
.
.
/**
 * ejbRemove method: Unregister your MBean.
 */
public void ejbRemove() {
    synchronized (lockObj) {
        System.out.println(">>> SnoopMBean Deactivating for --|" + this + "|--");
        if (snoopyON == null) {
            return;
        }
        try {
            System.out.println(">>> SnoopMBean Deactivating ==|" + snoopyON + "|== for --|" + this + "|--");
            MBeanFactory mbfactory = AdminServiceFactory.getMBeanFactory();
            mbfactory.deactivateMBean(snoopyON);
            System.out.println(">>> SnoopMBean Deactivation COMPLETED!");
        } catch (Exception e) {
            System.out.println(">>> SnoopMBean Deactivation FAILED:");
            e.printStackTrace();
        }
    }
}

 

What to do next

Compile the MBean Java files and package the resulting class files with the descriptor .xml file, into the enterprise bean JAR file.

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Related Tasks

Best practices for standard, dynamic, and open MBeans

 

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