FileDocCategorySizeDatePackage
Controller.javaAPI DocExample21196Thu May 23 09:32:50 BST 2002 sample.openmbean

Controller

public class Controller extends Basic implements DynamicMBean
Controls and coordinates all activities in the sample application.
author
Steve Perry

Fields Summary
public static final String
CONTROLLER_OBJECT_NAME
private MBeanServer
_server
private Queue
_queue
private int
_numberOfSuppliers
private int
_numberOfConsumers
private MBeanInfo
_MBeanInfo
MessageLog
_logger
Constructors Summary
public Controller()
Constructor. Creates and registers the Queues and performs initialization to get the controller up and running.

        super();
        try {
            //
            // Create attribute metadata:
            // - Queue
            //
            OpenMBeanAttributeInfo[] attributeInfo = new OpenMBeanAttributeInfo[4];
            attributeInfo[0] = new OpenMBeanAttributeInfoSupport(
                "NumberOfResets",
                "The number of times reset() has been called.",
                SimpleType.INTEGER,
                true,
                false,  // not writable
                false,
                new Integer(0),
                null
            );
            attributeInfo[1] = new OpenMBeanAttributeInfoSupport(
                "TraceOn",
                "Indicates whether or not tracing is on.",
                SimpleType.BOOLEAN,
                true,
                false,  // not writable
                false,
                new Boolean(false),
                null
            );
            attributeInfo[2] = new OpenMBeanAttributeInfoSupport(
                "DebugOn",
                "Indicates whether or not debugging is on.",
                SimpleType.BOOLEAN,
                true,
                false,  // not writable
                false,
                new Boolean(false),
                null
            );
            CompositeType queueOpenType = new CompositeType(
                "Queue",
                "Queue type as an open MBean composite type",
                new String[] {
                    "QueueSize",
                    "NumberOfItemsProcessed",
                    "AddWaitTime",
                    "RemoveWaitTime",
                    "QueueFull",
                    "QueueEmpty",
                    "Suspended",
                    "EndOfInput",
                    "NumberOfSuppliers",
                    "NumberOfConsumers"
                },
                new String[] {
                    "QueueSize",
                    "NumberOfItemsProcessed",
                    "AddWaitTime",
                    "RemoveWaitTime",
                    "QueueFull",
                    "QueueEmpty",
                    "Suspended",
                    "EndOfInput",
                    "NumberOfSuppliers",
                    "NumberOfConsumers"
                },
                new OpenType[] {
                    SimpleType.INTEGER,
                    SimpleType.LONG,
                    SimpleType.LONG,
                    SimpleType.LONG,
                    SimpleType.BOOLEAN,
                    SimpleType.BOOLEAN,
                    SimpleType.BOOLEAN,
                    SimpleType.BOOLEAN,
                    SimpleType.INTEGER,
                    SimpleType.INTEGER
                }
            );
            //
            // Create a new CompositeType that represents the Queue and
            /// its attributes.
            //
            attributeInfo[3] = new OpenMBeanAttributeInfoSupport(
                "Queue",
                "Consumer/Supplier Queue", // name
                queueOpenType,
                true,                      // isReadable?
                false,                     // isWritable?
                false,                     // isIs?
                null,                      // default value (null)
                null
            );
            //
            // Create constructor metadata
            //
            OpenMBeanConstructorInfo[] constructorInfo = new OpenMBeanConstructorInfoSupport[1];
            constructorInfo[0] = new OpenMBeanConstructorInfoSupport(
                "Constructor",
                "Controller Constructor",
                new OpenMBeanParameterInfo[0]
            );
            //
            // Create operation info:
            // - createWorker
            //
            OpenMBeanOperationInfo[] operationInfo = new OpenMBeanOperationInfo[1];
            OpenMBeanParameterInfo[] signature = new OpenMBeanParameterInfo[2];
            signature[0] = new OpenMBeanParameterInfoSupport(
                "role",           // name
                "The role this new worker thread will take on.",  // description
                SimpleType.STRING
            );
            signature[1] = new OpenMBeanParameterInfoSupport(
                "workFactor",  
                "The weighted work factor for this new worker thread.",
                SimpleType.INTEGER
            );
            operationInfo[0] = new OpenMBeanOperationInfoSupport(
                "createWorker",                // name
                "Creates a new Worker thread.",// description
                signature,                     // OpenMBeanParameterInfo[]
                SimpleType.VOID,               // return type
                MBeanOperationInfo.ACTION      // impact
            );
            //
            // Create Notification metadata:
            // - none
            //
            //
            // Now (finally!) create the MBean info metadata object
            //
            _MBeanInfo = new OpenMBeanInfoSupport(
                this.getClass().getName(),// DynamicMBean implementing class name
                "Controller Dynamic MBean.",            // description
                attributeInfo,          // MBeanAttributeInfo[]
                constructorInfo,        // MBeanConstructorInfo[]
                operationInfo,          // MBeanOperationInfo[]
                null                    // MBeanNotificationInfo[]
            );
            // find reference to (or create) MBean server
            this.getMBeanServer();
            // Create the queues
            _queue = new Queue();
            // Register the queue as an MBean
//            ObjectName objName = null;
//            objName = new ObjectName(_server.getDefaultDomain() + ":name=Queue");
//            trace("\tOBJECT NAME = " + objName);
//            _server.registerMBean(_queue, objName);
        } catch (Exception e) {
            e.printStackTrace();
            trace(e);
            return;
        }
        // Create the HTML adapter
        this.createHTMLAdapter();
Methods Summary
protected java.lang.StringbuildWorkerKey(java.lang.String role)
Builds the worker key from the role name

        StringBuffer buf = new StringBuffer();
        buf.append(Worker.OBJECT_NAME);
        buf.append(",role=");
        buf.append(role);
        return  buf.toString();
private voidcreateHTMLAdapter()
Creates the HTML adapter server and starts it running on its own thread of execution.

        int portNumber = 8090;
        HtmlAdaptorServer html = new HtmlAdaptorServer(portNumber);
        ObjectName html_name = null;
        try {
            html_name = new ObjectName("Adaptor:name=html,port=" + portNumber);
            trace("\tOBJECT NAME = " + html_name);
            _server.registerMBean(html, html_name);
        } catch (Exception e) {
            trace("\t!!! Could not create the HTML adaptor !!!");
            e.printStackTrace();
            trace(e);
            return;
        }
        html.start();
protected voidcreateNewWorker(java.lang.String role, int workFactor, int instanceId)
Creates and registers a worker MBean of the specified type.

        // Create the Worker and register it with the MBean server.
        Worker worker = null;
        ObjectName objName = null;
        StringBuffer buf = new StringBuffer();
        try {
            buf.append(buildWorkerKey(role));
            buf.append(",instanceId=");
            buf.append(instanceId);
            if (role.equalsIgnoreCase(Supplier.ROLE)) {
                worker = new Supplier(_queue, workFactor);
            } 
            else if (role.equalsIgnoreCase(Consumer.ROLE)) {
                worker = new Consumer(_queue, workFactor);
            }
            objName = new ObjectName(buf.toString());
            trace("\tOBJECT NAME = " + objName);
            _server.registerMBean(worker, objName);
            Thread t = new Thread(worker);
            t.start();
            if (role.equalsIgnoreCase(Supplier.ROLE)) {
                _numberOfSuppliers++;
            } 
            else if (role.equalsIgnoreCase(Consumer.ROLE)) {
                _numberOfConsumers++;
            }
        } catch (Exception e) {
            trace("Controller.main(): ERROR: " + "Could not register the Supplier MBean! Stack trace follows...");
            e.printStackTrace();
            trace(e);
            return;
        }
public voidcreateWorker(java.lang.String role, int workFactor)
Creates and starts a worker thread

        int index = getNumberOfWorkers(role);
        createNewWorker(role, workFactor, index + 1);
public java.lang.ObjectgetAttribute(java.lang.String attributeName)
Obtains the value of a specific attribute of the Dynamic MBean.

param
attribute The name of the attribute to be retrieved
return
The value of the attribute retrieved.
exception
AttributeNotFoundException
exception
MBeanException Wraps a java.lang.Exception thrown by the MBean's getter.
exception
ReflectionException Wraps a java.lang.Exception thrown while trying to invoke the getter.

        Object ret = null;
        if (attributeName.equals("ConsumerSupplierQueue")) {
            ret = this.getConsumerSupplierQueue();
        } 
        else 
            ret = super.getAttribute(attributeName);
        return  ret;
public javax.management.AttributeListgetAttributes(java.lang.String[] attributeNames)
Enables the values of several attributes of the Dynamic MBean.

param
attributes A list of the attributes to be retrieved.
return
The list of attributes retrieved.

        // no attributes...delegate to parent class
        return  super.getAttributes(attributeNames);
public java.util.QueuegetConsumerSupplierQueue()
Retrieves a reference to the Queue.

        return  _queue;
public javax.management.MBeanInfogetMBeanInfo()
Provides the exposed attributes and actions of the Dynamic MBean using an MBeanInfo object.

return
An instance of MBeanInfo allowing all attributes and actions exposed by this Dynamic MBean to be retrieved.

        return  (_MBeanInfo);
javax.management.MBeanServergetMBeanServer()
Obtains a reference to the MBean server. If at least one MBean server already exists, then a reference to that MBean server is returned. Otherwise a new instance is created.

        if (_server == null) {
            ArrayList mbeanServers = MBeanServerFactory.findMBeanServer(null);
            Iterator iter = mbeanServers.iterator();
            int aa = 1;
            while (iter.hasNext()) {
                MBeanServer mbs = (MBeanServer)iter.next();
                trace("QueueAgent.main(): INFO: " + "MBean server no. " + aa
                        + ":");
                Set set = mbs.queryMBeans(null, null);
                Iterator iter2 = set.iterator();
                while (iter2.hasNext()) {
                    ObjectInstance obji = (ObjectInstance)iter2.next();
                    trace("\tCLASSNAME={" + obji.getClassName() + "}, OBJECTNAME={"
                            + obji.getObjectName() + "}");
                }
                aa++;
            }
            _server = (mbeanServers.size() > 0) ? (MBeanServer)mbeanServers.get(0) :
                    MBeanServerFactory.createMBeanServer();
        }
        return  _server;
protected intgetNumberOfWorkers(java.lang.String role)
Returns the number of workers of each type

        int ret = 0;
        if (role.equalsIgnoreCase(Supplier.ROLE)) {
            ret = _numberOfSuppliers;
        } 
        else if (role.equalsIgnoreCase(Consumer.ROLE)) {
            ret = _numberOfConsumers;
        } 
        else {
            throw  new RuntimeMBeanException(new IllegalArgumentException("Controller.getNumberOfWorkers(): ERROR: "
                    + "Unknown role name \'" + role + "\'."));
        }
        return  ret;
protected OpenMBeanInfogetOpenMBeanInfo()

        return (OpenMBeanInfo)_MBeanInfo;
public java.lang.Objectinvoke(java.lang.String operationName, java.lang.Object[] params, java.lang.String[] signature)
Allows an action to be invoked on the Dynamic MBean.

param
actionName The name of the action to be invoked.
param
params An array containing the parameters to be set when the action is invoked.
param
signature An array containing the signature of the action. The class objects will be loaded through the same class loader as the one used for loading the MBean on which the action is invoked.
return
The object returned by the action, which represents the result of invoking the action on the MBean specified.
exception
MBeanException Wraps a java.lang.Exception thrown by the MBean's invoked method.
exception
ReflectionException Wraps a 

        Object ret = Void.TYPE;
        //
        // Turn the signature into a Class array so we can get the Method
        /// object and invoke the method, passing params
        //
        try {
            Class[] sign = new Class[signature.length];
            for (int aa = 0; aa < signature.length; aa++) {
                try {
                    sign[aa] = this.getClassFromString(signature[aa]);
                } catch (ClassNotFoundException e) {
                    throw  new RuntimeOperationsException(new IllegalArgumentException(
                            "Controller.invoke(): ERROR: " + "Bad argument \'"
                            + sign[aa] + " found when attempting to invoke operation \'"
                            + operationName + "\'!"));
                }
            }
            Method theMethod = this.getClass().getMethod(operationName, sign);
            //
            // If we got this far, then the requested method is on the
            /// Class, but is it on the management interface?
            //
            if (operationName.equals("createWorker")) {
                theMethod.invoke(this, params);
            } 
            else {
                // delegate to parent class
                ret = super.invoke(operationName, params, signature);
            }
        } catch (NoSuchMethodException e) {
            throw  new ReflectionException(e, e.getClass().getName());
        } catch (IllegalAccessException e) {
            throw  new ReflectionException(e, e.getClass().getName());
        } catch (InvocationTargetException e) {
            throw  new ReflectionException(e, e.getClass().getName());
        }
        return  ret;
public static voidmain(java.lang.String[] args)
The main method.

param
args String array containing arguments


                  
          
        MessageLog log = new MessageLog();
        if (args.length == 2) {
            int supplierWorkFactor = Integer.parseInt(args[0]);
            int consumerWorkFactor = Integer.parseInt(args[1]);
            System.out.println("Controller.main(): INFO: " + "supplierWorkFactor="
                    + supplierWorkFactor + ", consumerWorkFactor=" + consumerWorkFactor);
            log.write("Controller.main(): INFO: " + "supplierWorkFactor=" + 
                    supplierWorkFactor + ", consumerWorkFactor=" + consumerWorkFactor);
            Controller controller = new Controller();
            controller.enableTracing();
            MBeanServer server = controller.getMBeanServer();
            // Register the controller as an MBean
            ObjectName objName = null;
            try {
                objName = new ObjectName(Controller.CONTROLLER_OBJECT_NAME);
                System.out.println("\tOBJECT NAME = " + objName);
                log.write("\tOBJECT NAME = " + objName);
                server.registerMBean(controller, objName);
            } catch (Exception e) {
                System.out.println("Controller.main(): ERROR: " + "Could not register the Controller MBean! Stack trace follows...");
                log.write("Controller.main(): ERROR: " + "Could not register the Controller MBean! Stack trace follows...");
                e.printStackTrace();
                log.write(e);
                return;
            }
            controller.createWorker(Supplier.ROLE, supplierWorkFactor);
            controller.createWorker(Consumer.ROLE, consumerWorkFactor);
        } 
        else {
            System.out.println("Controller.main(): ERROR: Usage: " + "Controller supplier-weight consumer-weight");
            log.write("Controller.main(): ERROR: Usage: " + "Controller supplier-weight consumer-weight");
        }
public voidreset()
put your documentation comment here

    // nothing to do, have to implement, though...
public voidsetAttribute(javax.management.Attribute attribute)
Sets the value of a specific attribute of the Dynamic MBean

param
attribute The identification of the attribute to be set and the value it is to be set to.
exception
AttributeNotFoundException
exception
InvalidAttributeValueException
exception
MBeanException Wraps a java.lang.Exception thrown by the MBean's setter.
exception
ReflectionException Wraps a java.lang.Exception thrown while trying to invoke the MBean's setter.

        //
        // No writeable attributes on the management interface.
        // Delegate to parent class to implement management interface
        /// inheritance.
        //
        super.setAttribute(attribute);
public javax.management.AttributeListsetAttributes(javax.management.AttributeList attributes)
Sets the values of several attributes of the Dynamic MBean

param
name The object name of the MBean within which the attributes are to be set.
param
attributes A list of attributes: The identification of the attributes to be set and the values they are to be set to.
return
The list of attributes that were set, with their new values.

        //
        // No writeable attributes on the management interface...
        // Delegate to parent class.
        //
        return  super.setAttributes(attributes);
private voidtrace(java.lang.String message)
put your documentation comment here

param
message

        if (isTraceOn()) {
            System.out.println(message);
        }
        traceLog(message);
private voidtrace(java.lang.Throwable t)
put your documentation comment here

param
t

        traceLog(t);
private voidtraceLog(java.lang.Throwable t)
put your documentation comment here

param
t

        if (isTraceOn()) {
            _logger.write(t);
        }
private voidtraceLog(java.lang.String message)
put your documentation comment here

param
message


                
         
        if (isTraceOn()) {
            _logger.write(message);
        }