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 Long.valueOf(((Number) value).longValue());
if (value instanceof String) {
try {
long ctl = Long.parseLong((String) value);
return Long.valueOf(ctl);
} catch (NumberFormatException x) {
return Long.valueOf(0);
}
}
return Long.valueOf(0);
}
// Not in the spec but needed
private void removeAttributeChangeNotificationListener(
NotificationListener listener, String attributeName, Object handback)
throws MBeanException, RuntimeOperationsException, ListenerNotFoundException {
if (listener == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_LISTENER_CANNOT_BE_NULL.toLocalizedString()));
AttributeChangeNotificationFilter filter = new AttributeChangeNotificationFilter();
if (attributeName != null) {
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);
}
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;
}
}
public MX4JModelMBean() throws MBeanException, RuntimeOperationsException {
try {
load();
} catch (Exception x) {
Logger logger = getLogger();
logger.warn(
LocalizedStrings.MX4JModelMBean_CANNOT_RESTORE_PREVIOUSLY_SAVED_STATUS
.toLocalizedString(),
x);
}
}
public void setManagedResource(Object resource, String resourceType)
throws MBeanException, RuntimeOperationsException, InstanceNotFoundException,
InvalidTargetObjectTypeException {
if (resource == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_MANAGED_RESOURCE_CANNOT_BE_NULL.toLocalizedString()));
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;
}
public void setModelMBeanInfo(ModelMBeanInfo modelMBeanInfo)
throws MBeanException, RuntimeOperationsException {
if (modelMBeanInfo == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_MODELMBEANINFO_CANNOT_BE_NULL.toLocalizedString()));
if (!isModelMBeanInfoValid(modelMBeanInfo))
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_MODELMBEANINFO_IS_INVALID.toLocalizedString()));
m_modelMBeanInfo = (ModelMBeanInfo) modelMBeanInfo.clone();
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.DEBUG))
logger.debug("ModelMBeanInfo successfully set to: " + m_modelMBeanInfo);
// Only now the MBean can be registered in the MBeanServer
m_canBeRegistered = true;
}
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;
}
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(
LocalizedStrings.MX4JModelMBean_COULD_NOT_FIND_TARGET.toLocalizedString()));
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);
}
}
public AttributeList setAttributes(AttributeList attributes) {
if (attributes == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_LIST_CANNOT_BE_NULL.toLocalizedString()));
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 AttributeList getAttributes(String[] attributes) {
if (attributes == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_NAMES_CANNOT_BE_NULL.toLocalizedString()));
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;
}
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(
LocalizedStrings.MX4JModelMBean_RETURNED_TYPE_AND_DECLARED_TYPE_ARE_NOT_ASSIGNABLE
.toLocalizedString()));
}
}
public void sendAttributeChangeNotification(AttributeChangeNotification notification)
throws MBeanException, RuntimeOperationsException {
if (notification == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_NOTIFICATION_CANNOT_BE_NULL.toLocalizedString()));
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");
}
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 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;
}
}
}
public Object invoke(String method, Object[] arguments, String[] params)
throws MBeanException, ReflectionException {
if (method == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_METHOD_NAME_CANNOT_BE_NULL.toLocalizedString()));
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(
LocalizedStrings.MX4JModelMBean_MODELMBEANINFO_IS_NULL.toLocalizedString()));
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)
throw new MBeanException(
new ServiceNotFoundException(
LocalizedStrings.MX4JModelMBean_CANNOT_FIND_MODELMBEANOPERATIONINFO_FOR_OPERATION_0
.toLocalizedString(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(
LocalizedStrings.MX4JModelMBean_OPERATION_DESCRIPTOR_FOR_OPERATION_0_CANNOT_BE_NULL
.toLocalizedString(method)));
String role = (String) operationDescriptor.getFieldValue("role");
if (role == null || !role.equals("operation"))
throw new MBeanException(
new ServiceNotFoundException(
LocalizedStrings
.MX4JModelMBean_OPERATION_DESCRIPTOR_FIELD_ROLE_MUST_BE_OPERATION_NOT_0
.toLocalizedString(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(
LocalizedStrings.MX4JModelMBean_MBEAN_DESCRIPTOR_CANNOT_BE_NULL.toLocalizedString()));
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(LocalizedStrings.MX4JModelMBean_CANNOT_FIND_OPERATIONS_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, Long.valueOf(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 != MBeanOperationInfo.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(
LocalizedStrings.MX4JModelMBean_CANNOT_STORE_MODELMBEAN_AFTER_OPERATION_INVOCATION, x);
if (x instanceof MBeanException) throw (MBeanException) x;
else throw new MBeanException(x);
}
}
return returnValue;
}
public void setAttribute(Attribute attribute)
throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException,
ReflectionException {
if (attribute == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_CANNOT_BE_NULL.toLocalizedString()));
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(
LocalizedStrings.MX4JModelMBean_MODELMBEANINFO_IS_NULL.toLocalizedString());
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(
LocalizedStrings.MX4JModelMBean_CANNOT_FIND_MODELMBEANATTRIBUTEINFO_FOR_ATTRIBUTE_0
.toLocalizedString(attrName));
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute info is: " + attrInfo);
if (!attrInfo.isWritable())
throw new AttributeNotFoundException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_0_IS_NOT_WRITABLE.toLocalizedString(attrName));
// This returns a clone of the mbean descriptor, we use it read only
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null)
throw new AttributeNotFoundException(
LocalizedStrings.MX4JModelMBean_MBEAN_DESCRIPTOR_CANNOT_BE_NULL.toLocalizedString());
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(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_DESCRIPTOR_FOR_ATTRIBUTE_0_CANNOT_BE_NULL
.toLocalizedString(attrName));
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, Long.valueOf(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(LocalizedStrings.MX4JModelMBean_CANNOT_STORE_MODELMBEAN_AFTER_SETATTRIBUTE, x);
if (x instanceof MBeanException) throw (MBeanException) x;
else throw new MBeanException(x);
}
}
}
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(
LocalizedStrings.MX4JModelMBean_MX4JMODELMBEAN_IS_NOT_REGISTERED
.toLocalizedString()));
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;
}
}
public Object getAttribute(String attribute)
throws AttributeNotFoundException, MBeanException, ReflectionException {
if (attribute == null)
throw new RuntimeOperationsException(
new IllegalArgumentException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_NAME_CANNOT_BE_NULL.toLocalizedString()));
Logger logger = getLogger();
// I want the real info, not its clone
ModelMBeanInfo info = getModelMBeanInfo();
if (info == null)
throw new AttributeNotFoundException(
LocalizedStrings.MX4JModelMBean_MODELMBEANINFO_IS_NULL.toLocalizedString());
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(
LocalizedStrings.MX4JModelMBean_CANNOT_FIND_MODELMBEANATTRIBUTEINFO_FOR_ATTRIBUTE_0
.toLocalizedString(attribute));
if (logger.isEnabledFor(Logger.DEBUG)) logger.debug("Attribute info is: " + attrInfo);
if (!attrInfo.isReadable())
throw new AttributeNotFoundException(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_0_IS_NOT_READABLE.toLocalizedString(attribute));
// This returns a clone of the mbean descriptor, we use it read only
Descriptor mbeanDescriptor = info.getMBeanDescriptor();
if (mbeanDescriptor == null)
throw new AttributeNotFoundException(
LocalizedStrings.MX4JModelMBean_MBEAN_DESCRIPTOR_CANNOT_BE_NULL.toLocalizedString());
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(
LocalizedStrings.MX4JModelMBean_ATTRIBUTE_DESCRIPTOR_FOR_ATTRIBUTE_0_CANNOT_BE_NULL
.toLocalizedString(attribute));
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, Long.valueOf(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;
}
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(
LocalizedStrings.MX4JModelMBean_MX4JMODELMBEAN_IS_NOT_REGISTERED
.toLocalizedString()));
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);
}
}
