javax.management.modelmbean.RequiredModelMBean Maven / Gradle / Ivy
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/*
* Copyright (C) The MX4J Contributors.
* All rights reserved.
*
* This software is distributed under the terms of the MX4J License version 1.0.
* See the terms of the MX4J License in the documentation provided with this software.
*/
package javax.management.modelmbean;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Date;
import java.util.Iterator;
import javax.management.Attribute;
import javax.management.AttributeChangeNotification;
import javax.management.AttributeChangeNotificationFilter;
import javax.management.AttributeList;
import javax.management.AttributeNotFoundException;
import javax.management.Descriptor;
import javax.management.InstanceNotFoundException;
import javax.management.InvalidAttributeValueException;
import javax.management.ListenerNotFoundException;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanException;
import javax.management.MBeanInfo;
import javax.management.MBeanNotificationInfo;
import javax.management.MBeanRegistration;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.Notification;
import javax.management.NotificationBroadcasterSupport;
import javax.management.NotificationEmitter;
import javax.management.NotificationFilter;
import javax.management.NotificationListener;
import javax.management.ObjectName;
import javax.management.ReflectionException;
import javax.management.RuntimeErrorException;
import javax.management.RuntimeOperationsException;
import javax.management.ServiceNotFoundException;
import javax.management.loading.ClassLoaderRepository;
import mx4j.ImplementationException;
import mx4j.log.FileLogger;
import mx4j.log.Log;
import mx4j.log.Logger;
import mx4j.log.MBeanLogger;
import mx4j.persist.FilePersister;
import mx4j.persist.MBeanPersister;
import mx4j.persist.PersisterMBean;
import mx4j.util.Utils;
/**
* @version $Revision: 1.22 $
*/
public class RequiredModelMBean implements ModelMBean, MBeanRegistration, NotificationEmitter
{
private static final String OBJECT_RESOURCE_TYPE = "ObjectReference";
private static final ModelMBeanInfoSupport DEFAULT_INFO;
private static final ModelMBeanNotificationInfo GENERIC_INFO;
private static final ModelMBeanNotificationInfo ATTR_CHANGE_INFO;
static
{
String[] fields = new String[]{
"name=GENERIC",
"descriptorType=notification",
"log=T",
"severity=6",
"displayName=jmx.modelmbean.generic"};
GENERIC_INFO = new ModelMBeanNotificationInfo(new String[]{"jmx.modelmbean.generic"}, "GENERIC", "", new DescriptorSupport(fields));
fields = new String[]{
"name=ATTRIBUTE_CHANGE",
"descriptorType=notification",
"log=T",
"severity=6",
"displayName=jmx.attribute.change"};
ATTR_CHANGE_INFO = new ModelMBeanNotificationInfo(new String[]{"jmx.attribute.change"}, "ATTRIBUTE_CHANGE", "", new DescriptorSupport(fields));
DEFAULT_INFO = new ModelMBeanInfoSupport(RequiredModelMBean.class.getName(), null, null, null, null, null);
}
private static final int ALWAYS_STALE = 1;
private static final int NEVER_STALE = 2;
private static final int STALE = 3;
private static final int NOT_STALE = 4;
private static final int PERSIST_NEVER = -1;
private static final int PERSIST_ON_TIMER = -2;
private static final int PERSIST_ON_UPDATE = -3;
private static final int PERSIST_NO_MORE_OFTEN_THAN = -4;
private MBeanServer m_mbeanServer;
private Object m_managedResource;
private ModelMBeanInfo m_modelMBeanInfo;
private NotificationBroadcasterSupport m_generalBroadcaster = new NotificationBroadcasterSupport();
public RequiredModelMBean() throws MBeanException, RuntimeOperationsException
{
m_modelMBeanInfo = DEFAULT_INFO;
}
public RequiredModelMBean(ModelMBeanInfo info) throws MBeanException, RuntimeOperationsException
{
if (info == null)
throw new RuntimeOperationsException(new IllegalArgumentException("ModelMBeanInfo parameter can't be null"));
else
setModelMBeanInfo(info);
}
private Logger getLogger()
{
return Log.getLogger(getClass().getName());
}
public ObjectName preRegister(MBeanServer server, ObjectName name) throws Exception
{
if (name == null) throw new IllegalArgumentException("ObjectName is null");
m_mbeanServer = server;
return name;
}
public void postRegister(Boolean registrationDone)
{
if (!registrationDone.booleanValue()) clear();
}
public void preDeregister() throws Exception
{
}
public void postDeregister()
{
clear();
}
private void clear()
{
m_mbeanServer = null;
// PENDING: also remove generic listeners, attribute change listeners, log4j appenders...
}
public void setModelMBeanInfo(ModelMBeanInfo modelMBeanInfo) throws MBeanException, RuntimeOperationsException
{
if (m_mbeanServer != null) throw new RuntimeOperationsException(new IllegalStateException("setModelMBeanInfo cannot be called when ModelMBean is registered"));
if (modelMBeanInfo == null) throw new RuntimeOperationsException(new IllegalArgumentException("ModelMBeanInfo cannot be null"));
if (!isModelMBeanInfoValid(modelMBeanInfo)) throw new RuntimeOperationsException(new IllegalArgumentException("ModelMBeanInfo is invalid"));
m_modelMBeanInfo = new ModelMBeanInfoSupport(modelMBeanInfo);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBeanInfo successfully set to: " + m_modelMBeanInfo);
}
private boolean isModelMBeanInfoValid(ModelMBeanInfo info)
{
if (info == null || info.getClassName() == null) return false;
// PENDING: maybe more checks are needed
return true;
}
public void setManagedResource(Object resource, String resourceType) throws MBeanException, RuntimeOperationsException, InstanceNotFoundException, InvalidTargetObjectTypeException
{
if (!isResourceTypeSupported(resourceType)) throw new InvalidTargetObjectTypeException(resourceType);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Setting managed resource to be: " + resource);
m_managedResource = resource;
}
private boolean isResourceTypeSupported(String resourceType)
{
// For now only object reference is supported
return OBJECT_RESOURCE_TYPE.equalsIgnoreCase(resourceType);
}
private Object getManagedResource()
{
return m_managedResource;
}
public MBeanInfo getMBeanInfo()
{
return m_modelMBeanInfo == null ? null : (MBeanInfo)m_modelMBeanInfo.clone();
}
public void addAttributeChangeNotificationListener(NotificationListener listener, String attributeName, Object handback) throws MBeanException, RuntimeOperationsException, IllegalArgumentException
{
if (listener == null) throw new IllegalArgumentException("Listener cannot be null");
AttributeChangeNotificationFilter filter = new AttributeChangeNotificationFilter();
if (attributeName != null)
{
if (m_modelMBeanInfo.getAttribute(attributeName) == null) throw new RuntimeOperationsException(new IllegalArgumentException("No attribute named " + attributeName));
filter.enableAttribute(attributeName);
}
else
{
MBeanAttributeInfo[] ai = m_modelMBeanInfo.getAttributes();
for (int i = 0; i < ai.length; i++)
{
Descriptor d = ((ModelMBeanAttributeInfo)ai[i]).getDescriptor();
filter.enableAttribute((String)d.getFieldValue("name"));
}
}
getAttributeChangeBroadcaster().addNotificationListener(listener, filter, handback);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Listener " + listener + " for attribute " + attributeName + " added successfully, handback is " + handback);
}
public void addNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback) throws IllegalArgumentException
{
if (listener == null) throw new IllegalArgumentException("listener cannot be null");
m_generalBroadcaster.addNotificationListener(listener, filter, handback);
}
public MBeanNotificationInfo[] getNotificationInfo()
{
MBeanNotificationInfo[] notifications = m_modelMBeanInfo.getNotifications();
boolean hasGeneric = false;
boolean hasAttribute = false;
int toAdd = 2;
for (int i=0; i < notifications.length; i++) {
String name = notifications[i].getName();
if ("GENERIC".equals(name))
{
hasGeneric = true;
toAdd -= 1;
if (hasAttribute) break;
}
else if ("ATTRIBUTE_CHANGE".equals(name))
{
hasAttribute = true;
toAdd -= 1;
if (hasGeneric) break;
}
}
// clone the array, adding in missing notifications
MBeanNotificationInfo[] newNotifications = new MBeanNotificationInfo[notifications.length + toAdd];
System.arraycopy(notifications, 0, newNotifications, toAdd, notifications.length);
if (!hasAttribute) newNotifications[--toAdd] = ATTR_CHANGE_INFO;
if (!hasGeneric) newNotifications[--toAdd] = GENERIC_INFO;
return newNotifications;
}
public void removeAttributeChangeNotificationListener(NotificationListener listener, String attributeName) throws MBeanException, RuntimeOperationsException, ListenerNotFoundException
{
//todo there may be a problem here if the original handback was not null - should we go directly to removeListener(NotificationListener) ?
removeAttributeChangeNotificationListener(listener, attributeName, null);
}
// Not in the spec but needed
private void removeAttributeChangeNotificationListener(NotificationListener listener, String attributeName, Object handback) throws MBeanException, RuntimeOperationsException, ListenerNotFoundException
{
if (listener == null) throw new ListenerNotFoundException("listener is null");
AttributeChangeNotificationFilter filter = new AttributeChangeNotificationFilter();
if (attributeName != null)
{
if (m_modelMBeanInfo.getAttribute(attributeName) == null) throw new RuntimeOperationsException(new IllegalArgumentException("No attribute named " + attributeName));
filter.enableAttribute(attributeName);
}
else
{
MBeanAttributeInfo[] ai = m_modelMBeanInfo.getAttributes();
for (int i = 0; i < ai.length; i++)
{
Descriptor d = ((ModelMBeanAttributeInfo)ai[i]).getDescriptor();
filter.enableAttribute((String)d.getFieldValue("name"));
}
}
getAttributeChangeBroadcaster().removeNotificationListener(listener, filter, handback);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Listener " + listener + " for attribute " + attributeName + " removed successfully, handback is " + handback);
}
public void removeNotificationListener(NotificationListener listener) throws RuntimeOperationsException, ListenerNotFoundException
{
m_generalBroadcaster.removeNotificationListener(listener);
}
public void removeNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback) throws RuntimeOperationsException, ListenerNotFoundException
{
m_generalBroadcaster.removeNotificationListener(listener, filter, handback);
}
public void sendAttributeChangeNotification(Attribute oldAttribute, Attribute newAttribute) throws MBeanException, RuntimeOperationsException
{
if (oldAttribute == null || newAttribute == null) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute cannot be null"));
if (!oldAttribute.getName().equals(newAttribute.getName())) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute names cannot be different"));
// TODO: the source must be the object name of the MBean if the listener was registered through MBeanServer
Object oldValue = oldAttribute.getValue();
AttributeChangeNotification n = new AttributeChangeNotification(this,
1,
System.currentTimeMillis(),
"Attribute value changed",
oldAttribute.getName(),
oldValue == null ? null : oldValue.getClass().getName(),
oldValue,
newAttribute.getValue());
sendAttributeChangeNotification(n);
}
public void sendAttributeChangeNotification(AttributeChangeNotification notification) throws MBeanException, RuntimeOperationsException
{
if (notification == null) throw new RuntimeOperationsException(new IllegalArgumentException("Notification cannot be null"));
getAttributeChangeBroadcaster().sendNotification(notification);
Logger modelMBeanLogger = getModelMBeanLogger(notification.getType());
if (modelMBeanLogger != null) if (modelMBeanLogger.isEnabledFor(Logger.DEBUG)) modelMBeanLogger.debug("ModelMBean log: " + new Date() + " - " + notification);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute change notification " + notification + " sent");
}
public void sendNotification(String message) throws MBeanException, RuntimeOperationsException
{
if (message == null) throw new RuntimeOperationsException(new IllegalArgumentException("message is null"));
Notification notification = new Notification("jmx.modelmbean.generic", this, 1, message);
sendNotification(notification);
}
public void sendNotification(Notification notification) throws MBeanException, RuntimeOperationsException
{
if (notification == null) throw new RuntimeOperationsException(new IllegalArgumentException("notification is null"));
m_generalBroadcaster.sendNotification(notification);
}
public AttributeList getAttributes(String[] attributes)
{
if (attributes == null) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute names cannot be null"));
Logger logger = getLogger();
AttributeList list = new AttributeList();
for (int i = 0; i < attributes.length; ++i)
{
String attrName = attributes[i];
Attribute attribute = null;
try
{
Object value = getAttribute(attrName);
attribute = new Attribute(attrName, value);
list.add(attribute);
}
catch (Exception x)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("getAttribute for attribute " + attrName + " failed", x);
// And go on with the next attribute
}
}
return list;
}
public Object getAttribute(String attribute) throws AttributeNotFoundException, MBeanException, ReflectionException
{
if (attribute == null) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute name cannot be null"));
Logger logger = getLogger();
// I want the real info, not its clone
ModelMBeanInfo info = getModelMBeanInfo();
if (info == null) throw new AttributeNotFoundException("ModelMBeanInfo is null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBeanInfo is: " + info);
// This is a clone, we use it read only
ModelMBeanAttributeInfo attrInfo = info.getAttribute(attribute);
if (attrInfo == null) throw new AttributeNotFoundException("Cannot find ModelMBeanAttributeInfo for attribute " + attribute);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute info is: " + attrInfo);
if (!attrInfo.isReadable()) throw new AttributeNotFoundException("Attribute " + attribute + " is not readable");
// This returns a clone of the mbean descriptor, we use it read only
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null) throw new AttributeNotFoundException("MBean descriptor cannot be null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("MBean descriptor is: " + mbeanDescriptor);
// This descriptor is a clone
Descriptor attributeDescriptor = attrInfo.getDescriptor();
if (attributeDescriptor == null) throw new AttributeNotFoundException("Attribute descriptor for attribute " + attribute + " cannot be null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute descriptor is: " + attributeDescriptor);
Object returnValue = null;
String lastUpdateField = "lastUpdatedTimeStamp";
int staleness = getStaleness(attributeDescriptor, mbeanDescriptor, lastUpdateField);
if (staleness == ALWAYS_STALE || staleness == STALE)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Value is stale");
String getter = (String)attributeDescriptor.getFieldValue("getMethod");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("getMethod field is: " + getter);
if (getter == null)
{
// No getter, use default value
returnValue = attributeDescriptor.getFieldValue("default");
if (returnValue != null)
{
// Check if the return type is of the same type
// As an extension allow covariant return type
Class returned = returnValue.getClass();
Class declared = loadClassWithContextClassLoader(attrInfo.getType());
checkAssignability(returned, declared);
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("getAttribute for attribute " + attribute + " returns default value: " + returnValue);
}
else
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Invoking attribute getter...");
// As an extension, allow attributes to be called on target objects also
Object target = resolveTargetObject(attributeDescriptor);
returnValue = invokeMethod(target, getter, new Class[0], new Object[0]);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Returned value is: " + returnValue);
if (returnValue != null)
{
// Check if the return type is of the same type
// As an extension allow covariant return type
Class returned = returnValue.getClass();
Class declared = loadClassWithContextClassLoader(attrInfo.getType());
checkAssignability(returned, declared);
}
// Cache the new value only if caching is needed
if (staleness != ALWAYS_STALE)
{
attributeDescriptor.setField("value", returnValue);
attributeDescriptor.setField(lastUpdateField, new Long(System.currentTimeMillis()));
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Returned value has been cached");
// And now replace the descriptor with the updated clone
info.setDescriptor(attributeDescriptor, "attribute");
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("getAttribute for attribute " + attribute + " returns invoked value: " + returnValue);
}
}
else
{
// Return cached value
returnValue = attributeDescriptor.getFieldValue("value");
if (returnValue != null)
{
// Check if the return type is of the same type
// As an extension allow covariant return type
Class returned = returnValue.getClass();
Class declared = loadClassWithContextClassLoader(attrInfo.getType());
checkAssignability(returned, declared);
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("getAttribute for attribute " + attribute + " returns cached value: " + returnValue);
}
// Puff, everything went ok
return returnValue;
}
public AttributeList setAttributes(AttributeList attributes)
{
if (attributes == null) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute list cannot be null"));
Logger logger = getLogger();
AttributeList list = new AttributeList();
for (Iterator i = attributes.iterator(); i.hasNext();)
{
Attribute attribute = (Attribute)i.next();
String name = attribute.getName();
try
{
setAttribute(attribute);
list.add(attribute);
}
catch (Exception x)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("setAttribute for attribute " + name + " failed", x);
// And go on with the next one
}
}
return list;
}
public void setAttribute(Attribute attribute) throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException, ReflectionException
{
if (attribute == null) throw new RuntimeOperationsException(new IllegalArgumentException("Attribute cannot be null"));
Logger logger = getLogger();
// No need to synchronize: I work mostly on clones
// I want the real info, not its clone
ModelMBeanInfo info = getModelMBeanInfo();
if (info == null) throw new AttributeNotFoundException("ModelMBeanInfo is null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBeanInfo is: " + info);
String attrName = attribute.getName();
Object attrValue = attribute.getValue();
// This is a clone, we use it read only
ModelMBeanAttributeInfo attrInfo = info.getAttribute(attrName);
if (attrInfo == null) throw new AttributeNotFoundException("Cannot find ModelMBeanAttributeInfo for attribute " + attrName);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute info is: " + attrInfo);
if (!attrInfo.isWritable()) throw new AttributeNotFoundException("Attribute " + attrName + " is not writable");
// This returns a clone of the mbean descriptor, we use it read only
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null) throw new AttributeNotFoundException("MBean descriptor cannot be null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("MBean descriptor is: " + mbeanDescriptor);
// This descriptor is a clone
Descriptor attributeDescriptor = attrInfo.getDescriptor();
if (attributeDescriptor == null) throw new AttributeNotFoundException("Attribute descriptor for attribute " + attrName + " cannot be null");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute descriptor is: " + attributeDescriptor);
String lastUpdateField = "lastUpdatedTimeStamp";
Object oldValue = null;
try
{
oldValue = getAttribute(attrName);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Previous value of attribute " + attrName + ": " + oldValue);
}
catch (Exception x)
{
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Cannot get previous value of attribute " + attrName, x);
}
// Check if setMethod is present
String method = (String)attributeDescriptor.getFieldValue("setMethod");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("setMethod field is: " + method);
if (method != null)
{
Class declared = loadClassWithContextClassLoader(attrInfo.getType());
if (attrValue != null)
{
Class parameter = attrValue.getClass();
checkAssignability(parameter, declared);
}
// As an extension, allow attributes to be called on target objects also
Object target = resolveTargetObject(attributeDescriptor);
invokeMethod(target, method, new Class[]{declared}, new Object[]{attrValue});
// Cache the value only if currencyTimeLimit is not 0, ie it is not always stale
int staleness = getStaleness(attributeDescriptor, mbeanDescriptor, lastUpdateField);
if (staleness != ALWAYS_STALE)
{
attributeDescriptor.setField("value", attrValue);
attributeDescriptor.setField(lastUpdateField, new Long(System.currentTimeMillis()));
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Attribute's value has been cached");
}
else
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Always stale, avoiding to cache attribute's value");
}
}
else
{
if (attrValue != null)
{
Class parameter = attrValue.getClass();
Class declared = loadClassWithContextClassLoader(attrInfo.getType());
checkAssignability(parameter, declared);
}
// Always store the value in the descriptor: no setMethod
attributeDescriptor.setField("value", attrValue);
}
// And now replace the descriptor with the updated clone
info.setDescriptor(attributeDescriptor, "attribute");
// Send notifications to listeners
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Sending attribute change notifications");
sendAttributeChangeNotification(new Attribute(attrName, oldValue), attribute);
// Persist this ModelMBean
boolean persistNow = shouldPersistNow(attributeDescriptor, mbeanDescriptor, lastUpdateField);
if (persistNow)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persisting this ModelMBean...");
try
{
store();
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("ModelMBean persisted successfully");
}
catch (Exception x)
{
logger.error("Cannot store ModelMBean after setAttribute", x);
if (x instanceof MBeanException)
throw (MBeanException)x;
else
throw new MBeanException(x);
}
}
}
public Object invoke(String method, Object[] arguments, String[] params) throws MBeanException, ReflectionException
{
if (method == null) throw new RuntimeOperationsException(new IllegalArgumentException("Method name cannot be null"));
if (arguments == null) arguments = new Object[0];
if (params == null) params = new String[0];
Logger logger = getLogger();
// Find operation descriptor
ModelMBeanInfo info = getModelMBeanInfo();
if (info == null) throw new MBeanException(new ServiceNotFoundException("ModelMBeanInfo is null"));
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBeanInfo is: " + info);
// This is a clone, we use it read only
ModelMBeanOperationInfo operInfo = info.getOperation(method);
if (operInfo == null)
{
// Bug #940161 Required ModelMBean methods are not invoked
try
{
// Look in RMMB public methods
Class[] clzArgs = new Class[params.length];
for (int i = 0; i < clzArgs.length; i++)
{
ClassLoader loader = getClass().getClassLoader();
if (loader == null) loader = Thread.currentThread().getContextClassLoader();
clzArgs[i] = loader.loadClass(params[i]);
}
// Class.getMethod only returns public methods
Method invocationMethod = getClass().getMethod(method, clzArgs);
operInfo = new ModelMBeanOperationInfo("", invocationMethod);
}
catch (Exception e)
{
throw new MBeanException(new ServiceNotFoundException("Cannot find ModelMBeanOperationInfo for operation " + method));
}
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Operation info is: " + operInfo);
// This descriptor is a clone
Descriptor operationDescriptor = operInfo.getDescriptor();
if (operationDescriptor == null) throw new MBeanException(new ServiceNotFoundException("Operation descriptor for operation " + method + " cannot be null"));
String role = (String)operationDescriptor.getFieldValue("role");
if (role == null || !role.equals("operation")) throw new MBeanException(new ServiceNotFoundException("Operation descriptor field 'role' must be 'operation', not " + role));
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Operation descriptor is: " + operationDescriptor);
// This returns a clone of the mbean descriptor, we use it read only
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null) throw new MBeanException(new ServiceNotFoundException("MBean descriptor cannot be null"));
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("MBean descriptor is: " + mbeanDescriptor);
Object returnValue = null;
String lastUpdateField = "lastReturnedTimeStamp";
// Check if the method should be invoked given the cache settings
int staleness = getStaleness(operationDescriptor, mbeanDescriptor, lastUpdateField);
if (staleness == ALWAYS_STALE || staleness == STALE)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Value is stale");
// Find parameters classes
Class[] parameters = null;
try
{
parameters = Utils.loadClasses(Thread.currentThread().getContextClassLoader(), params);
}
catch (ClassNotFoundException x)
{
logger.error("Cannot find operation's parameter classes", x);
throw new ReflectionException(x);
}
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Invoking operation...");
// Find target object
Object target = resolveTargetObject(operationDescriptor);
returnValue = invokeMethod(target, method, parameters, arguments);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Returned value is: " + returnValue);
if (returnValue != null)
{
Class parameter = returnValue.getClass();
Class declared = loadClassWithContextClassLoader(operInfo.getReturnType());
checkAssignability(parameter, declared);
}
// Cache the new value only if caching is needed
if (staleness != ALWAYS_STALE)
{
operationDescriptor.setField("lastReturnedValue", returnValue);
operationDescriptor.setField(lastUpdateField, new Long(System.currentTimeMillis()));
if (logger.isEnabledFor(Logger.TRACE))
{
logger.trace("Returned value has been cached");
}
// And now replace the descriptor with the updated clone
info.setDescriptor(operationDescriptor, "operation");
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("invoke for operation " + method + " returns invoked value: " + returnValue);
}
else
{
// Return cached value
returnValue = operationDescriptor.getFieldValue("lastReturnedValue");
if (returnValue != null)
{
Class parameter = returnValue.getClass();
Class declared = loadClassWithContextClassLoader(operInfo.getReturnType());
checkAssignability(parameter, declared);
}
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("invoke for operation " + method + " returns cached value: " + returnValue);
}
// As an extension, persist this model mbean also after operation invocation, but using only
// settings provided in the operation descriptor, without falling back to defaults set in
// the MBean descriptor
boolean persistNow = shouldPersistNow(operationDescriptor, null, lastUpdateField);
int impact = operInfo.getImpact();
if (persistNow && impact != ModelMBeanOperationInfo.INFO)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persisting this ModelMBean...");
try
{
store();
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("ModelMBean persisted successfully");
}
catch (Exception x)
{
logger.error("Cannot store ModelMBean after operation invocation", x);
if (x instanceof MBeanException)
throw (MBeanException)x;
else
throw new MBeanException(x);
}
}
return returnValue;
}
private Object resolveTargetObject(Descriptor descriptor) throws MBeanException
{
Logger logger = getLogger();
Object target = descriptor.getFieldValue("targetObject");
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("targetObject is: " + target);
if (target == null)
{
target = getManagedResource();
}
else
{
String targetObjectType = (String)descriptor.getFieldValue("targetObjectType");
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("targetObjectType is: " + targetObjectType);
if (targetObjectType == null)
{
// Not defined, assume object reference
targetObjectType = OBJECT_RESOURCE_TYPE;
}
if (!isResourceTypeSupported(targetObjectType)) throw new MBeanException(new InvalidTargetObjectTypeException(targetObjectType));
}
return target;
}
public void load() throws MBeanException, RuntimeOperationsException, InstanceNotFoundException
{
PersisterMBean persister = findPersister();
if (persister != null)
{
ModelMBeanInfo info = (ModelMBeanInfo)persister.load();
setModelMBeanInfo(info);
}
}
public void store() throws MBeanException, RuntimeOperationsException, InstanceNotFoundException
{
PersisterMBean persister = findPersister();
if (persister != null)
{
// Take a clone to avoid synchronization problems
ModelMBeanInfo info = (ModelMBeanInfo)getMBeanInfo();
persister.store(info);
}
}
protected ClassLoaderRepository getClassLoaderRepository()
{
if (m_mbeanServer != null)
return m_mbeanServer.getClassLoaderRepository();
else
return null;
}
private boolean shouldPersistNow(Descriptor attribute, Descriptor mbean, String lastUpdateField)
{
int persist = getPersistPolicy(attribute, mbean);
if (persist == PERSIST_NO_MORE_OFTEN_THAN)
{
Long period = getFieldTimeValue(attribute, mbean, "persistPeriod");
long now = System.currentTimeMillis();
Long lastUpdate = (Long)attribute.getFieldValue(lastUpdateField);
if (now - lastUpdate.longValue() < period.longValue())
return false;
else
return true;
}
else if (persist == PERSIST_NEVER)
{
return false;
}
else if (persist == PERSIST_ON_TIMER)
{
return false;
}
else if (persist == PERSIST_ON_UPDATE)
{
return true;
}
else
{
throw new ImplementationException("Invalid persist value");
}
}
private int getPersistPolicy(Descriptor descriptor, Descriptor mbean)
{
Logger logger = getLogger();
String persist = (String)descriptor.getFieldValue("persistPolicy");
if (persist == null && mbean != null) persist = (String)mbean.getFieldValue("persistPolicy");
if (persist == null)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("No persist policy defined, assuming Never");
return PERSIST_NEVER;
}
else
{
if (persist.equals("Never"))
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persist never");
return PERSIST_NEVER;
}
else if (persist.equals("OnUpdate"))
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persist on update");
return PERSIST_ON_UPDATE;
}
else if (persist.equals("OnTimer"))
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persist on update");
return PERSIST_ON_TIMER;
}
else if (persist.equals("NoMoreOftenThan"))
{
if (logger.isEnabledFor(Logger.TRACE))
{
Long period = getFieldTimeValue(descriptor, mbean, "persistPeriod");
logger.trace("Persist no more often than " + period);
}
return PERSIST_NO_MORE_OFTEN_THAN;
}
else
{
// Garbage, assuming Never
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Invalid persist policy, assuming persist never");
return PERSIST_NEVER;
}
}
}
private int getStaleness(Descriptor attribute, Descriptor mbean, String lastUpdateField)
{
Logger logger = getLogger();
Long currencyTimeLimit = getFieldTimeValue(attribute, mbean, "currencyTimeLimit");
if (currencyTimeLimit == null)
{
// No time limit defined
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("No currencyTimeLimit defined, assuming always stale");
return ALWAYS_STALE;
}
else
{
long ctl = currencyTimeLimit.longValue() * 1000;
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("currencyTimeLimit is (ms): " + ctl);
if (ctl == 0)
{
// Never stale
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Never stale");
return NEVER_STALE;
}
else if (ctl < 0) // this should be == -1 but the other cases are in the air
{
// Always stale
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Always stale");
return ALWAYS_STALE;
}
else
{
Long timestamp = (Long)attribute.getFieldValue(lastUpdateField);
long luts = 0;
if (timestamp != null) luts = timestamp.longValue();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug(lastUpdateField + " is: " + luts);
long now = System.currentTimeMillis();
if (now < luts + ctl)
{
// Seems to be not stale, but has been set at least once ?
if (timestamp == null)
{
// Return stale to call it the first time
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Stale since was never set");
return STALE;
}
else
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Not stale");
return NOT_STALE;
}
}
else
{
// Stale
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Stale");
return STALE;
}
}
}
}
private Long getFieldTimeValue(Descriptor descriptor, Descriptor mbean, String field)
{
Logger logger = getLogger();
Object value = descriptor.getFieldValue(field);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Descriptor's " + field + " field: " + value);
if (value == null && mbean != null)
{
value = mbean.getFieldValue(field);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("MBean's " + field + " field: " + value);
if (value == null) return null;
}
if (value instanceof Number) return new Long(((Number)value).longValue());
if (value instanceof String)
{
try
{
long ctl = Long.parseLong((String)value);
return new Long(ctl);
}
catch (NumberFormatException x)
{
return new Long(0);
}
}
return new Long(0);
}
private Object invokeMethod(Object target, String methodName, Class[] params, Object[] args) throws MBeanException, ReflectionException
{
// First try on this instance, then on the target
Object realTarget = null;
Method method = null;
try
{
realTarget = this;
method = realTarget.getClass().getMethod(methodName, params);
}
catch (NoSuchMethodException x)
{
realTarget = target;
}
if (realTarget == null) throw new MBeanException(new ServiceNotFoundException("Could not find target"));
if (method == null)
{
try
{
method = realTarget.getClass().getMethod(methodName, params);
}
catch (NoSuchMethodException x)
{
throw new ReflectionException(x);
}
}
try
{
Object value = method.invoke(realTarget, args);
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Method invocation returned value: " + value);
return value;
}
catch (IllegalAccessException x)
{
throw new ReflectionException(x);
}
catch (IllegalArgumentException x)
{
throw new MBeanException(x);
}
catch (InvocationTargetException x)
{
Throwable t = x.getTargetException();
if (t instanceof Error)
throw new MBeanException(new RuntimeErrorException((Error)t));
else
throw new MBeanException((Exception)t);
}
}
private Logger getModelMBeanLogger(String notificationType) throws MBeanException
{
// Get a copy to avoid synchronization
ModelMBeanInfo info = getModelMBeanInfo();
// First look if there is a suitable notification descriptor, otherwise use MBean descriptor
Descriptor descriptor = null;
Logger modelMBeanLogger = null;
if (notificationType != null)
{
descriptor = info.getDescriptor(notificationType, "notification");
modelMBeanLogger = findLogger(descriptor);
}
if (modelMBeanLogger == null)
{
descriptor = info.getMBeanDescriptor();
modelMBeanLogger = findLogger(descriptor);
if (modelMBeanLogger != null) return modelMBeanLogger;
}
return null;
}
private Logger findLogger(Descriptor descriptor)
{
Logger logger = getLogger();
if (descriptor == null)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Can't find MBean logger, descriptor is null");
return null;
}
String log = (String)descriptor.getFieldValue("log");
String location = (String)descriptor.getFieldValue("logFile");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Log fields: log=" + log + ", file=" + location);
if (log == null || !Boolean.valueOf(log).booleanValue())
{
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Logging is not supported by this ModelMBean");
return null;
}
// Logger is supported, where log to ?
if (location == null)
{
// As an extension, see if the field logMBean has been defined
location = (String)descriptor.getFieldValue("logMBean");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Log fields: mbean=" + location);
if (location == null)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Logging is not supported by this ModelMBean");
return null;
}
// It seems that the user wants to delegate a registered mbean to log
try
{
ObjectName objectName = new ObjectName(location);
MBeanServer server = getMBeanServer();
if (server == null) throw new MBeanException(new IllegalStateException("RequiredModelMBean is not registered"));
if (server.isRegistered(objectName))
{
MBeanLogger l = new MBeanLogger(server, objectName);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBean log supported by delegating to this MBean: " + objectName);
return l;
}
return null;
}
catch (MalformedObjectNameException x)
{
// Ah, was not a correct object name
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Specified logMBean field does not contain a valid ObjectName: " + location);
return null;
}
catch (MBeanException x)
{
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("logMBean field does not specify an MBean that supports logging delegation", x);
return null;
}
}
else
{
// User decided to log to a file
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("ModelMBean log supported on file system");
return new FileLogger(location);
}
}
private NotificationBroadcasterSupport getAttributeChangeBroadcaster()
{
return m_generalBroadcaster;
}
private MBeanServer getMBeanServer()
{
return m_mbeanServer;
}
private ModelMBeanInfo getModelMBeanInfo()
{
// No cloning performed
return m_modelMBeanInfo;
}
private PersisterMBean findPersister() throws MBeanException, InstanceNotFoundException
{
Logger logger = getLogger();
ModelMBeanInfo info = getModelMBeanInfo();
if (info == null)
{
// Not yet initialized
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Can't find persister, ModelMBeanInfo is null");
return null;
}
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null)
{
// This is normally should not happen if ModelMBeanInfoSupport is used
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Can't find persister, MBean descriptor is null");
return null;
}
String location = (String)mbeanDescriptor.getFieldValue("persistLocation");
String name = (String)mbeanDescriptor.getFieldValue("persistName");
String mbeanName = (String)mbeanDescriptor.getFieldValue("name");
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Persistence fields: location=" + location + ", name=" + name);
if (mbeanName == null && name == null)
{
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Persistence is not supported by this ModelMBean");
return null;
}
// Try to see if this mbean should delegate to another mbean
if (name != null)
{
try
{
ObjectName objectName = new ObjectName(name.trim());
// OK, a valid object name
MBeanServer server = getMBeanServer();
if (server == null) throw new MBeanException(new IllegalStateException("RequiredModelMBean is not registered"));
if (server.isRegistered(objectName) && server.isInstanceOf(objectName, PersisterMBean.class.getName()))
{
// OK, the given mbean is registered with this mbean server
PersisterMBean persister = new MBeanPersister(server, objectName);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Persistence is delegated to this MBean: " + objectName);
return persister;
}
else
{
throw new InstanceNotFoundException(objectName.toString());
}
}
catch (MalformedObjectNameException ignored)
{
// It does not delegates to another mbean, use default
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Persistence is not delegated to another MBean");
}
// Default is serialization to file
FilePersister persister = new FilePersister(location, name);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Persistence is realized through file system in " + persister.getFileName());
return persister;
}
else
{
// Only location given, use MBean name
FilePersister persister = new FilePersister(location, mbeanName);
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Persistence is realized through file system in " + persister.getFileName());
return persister;
}
}
private Class loadClassWithContextClassLoader(String name)
{
try
{
return Utils.loadClass(Thread.currentThread().getContextClassLoader(), name);
}
catch (ClassNotFoundException x)
{
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Cannot find attribute's declared return class", x);
return null;
}
}
private void checkAssignability(Class parameter, Class declared) throws MBeanException
{
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG))
{
logger.debug("The class of the parameter is: " + parameter);
if (parameter != null) logger.debug("The classloder of the parameter's class is: " + parameter.getClassLoader());
logger.debug("The class declared as type of the attribute is: " + declared);
if (declared != null) logger.debug("The classloader of the declared parameter's class is: " + declared.getClassLoader());
}
boolean assignable = false;
if (declared == null || parameter == null)
assignable = false;
else if (declared == boolean.class && parameter == Boolean.class)
assignable = true;
else if (declared == byte.class && parameter == Byte.class)
assignable = true;
else if (declared == char.class && parameter == Character.class)
assignable = true;
else if (declared == short.class && parameter == Short.class)
assignable = true;
else if (declared == int.class && parameter == Integer.class)
assignable = true;
else if (declared == long.class && parameter == Long.class)
assignable = true;
else if (declared == float.class && parameter == Float.class)
assignable = true;
else if (declared == double.class && parameter == Double.class)
assignable = true;
else
assignable = declared.isAssignableFrom(parameter);
if (!assignable)
{
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Parameter value's class and attribute's declared return class are not assignable");
throw new MBeanException(new InvalidAttributeValueException("Returned type and declared type are not assignable"));
}
}
}