CODEWITHSUNDEEP
javajmx
step-by-step
step-by-step

Reputation: 321

No operation found on MBean

Basically I am following the standard basic JMX tutorial and registering a MXBean with two methods.

public interface QueueSamplerMXBean {
    public QueueSample getQueueSample();
    public void clearQueue();
}

However, when I try to query the registered MBean, it only returns the clearQueue. Here is my sample program:

MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();

// Construct the ObjectName for the QueueSampler MXBean we will register
ObjectName mxbeanName = new ObjectName("com.example:type=QueueSampler");

// Create the Queue Sampler MXBean
Queue<String> queue = new ArrayBlockingQueue<String>(10);
queue.add("Request-1");
queue.add("Request-2");
queue.add("Request-3");
QueueSampler mxbean = new QueueSampler(queue);

// Register the Queue Sampler MXBean
mbs.registerMBean(mxbean, mxbeanName);

MBeanInfo info = mbs.getMBeanInfo(mxbeanName);
for(MBeanOperationInfo op : info.getOperations()) {
    System.out.println("operation = " + op.getName());
}

I think this is the reason why I keeps getting "java.lang.IllegalArgumentException. ... No operation XXXXXX(method name invoked) found on MBean ..... I am getting this exception while trying to invoke the MXBean method through Jolokia agent (JSON to JMX bridge). I have no problem invoking methods with void return type.

Anyone have any clues why getOperations does NOT return me the method with an JavaBean object as a return type? This is so weird. I must be missing something really simple.

Thanks!

Upvotes: 2

Views: 1610

Answers (2)

Heiko Rupp
Heiko Rupp

Reputation: 30994

I bet you have an attribute queueSample on your MBean instead, as getFoo is usually turned in to a readable attribute foo , setFoo into a writable one and if you have getter and setter, the attribute is r/w.

Use a tool like jconsole to connect to the VM and inspect your MBean.

Upvotes: 1

Nicholas
Nicholas

Reputation: 16066

The method should be:

public QueueSampleMBean getQueueSample();

And QueueSample should implement QueueSampleMBean (and only expose simple types).

Upvotes: 0

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