org.jboss.mx.mxbean.MXBeanDelegate Maven / Gradle / Ivy
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* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.mx.mxbean;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.Map;
import javax.management.Attribute;
import javax.management.AttributeList;
import javax.management.AttributeNotFoundException;
import javax.management.DynamicMBean;
import javax.management.InvalidAttributeValueException;
import javax.management.JMException;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanException;
import javax.management.MBeanInfo;
import javax.management.MBeanRegistration;
import javax.management.MBeanServer;
import javax.management.NotCompliantMBeanException;
import javax.management.NotificationBroadcasterSupport;
import javax.management.NotificationEmitter;
import javax.management.ObjectName;
import javax.management.ReflectionException;
import javax.management.openmbean.OpenMBeanAttributeInfo;
import javax.management.openmbean.OpenMBeanInfo;
import org.jboss.logging.Logger;
import org.jboss.mx.server.ExceptionHandler;
/**
* MXBeanDelegate.
*
* FIXME: Reflection madness
* @author Adrian Brock
* @version $Revision: 85945 $
*/
public class MXBeanDelegate extends NotificationBroadcasterSupport implements DynamicMBean, MBeanRegistration, NotificationEmitter
{
/** The logger */
private static final Logger log = Logger.getLogger(MXBeanDelegate.class);
/** The implementation object */
private Object implementation;
/** The management interface */
private Class mbeanInterface;
/** The cached mbeaninfo */
private OpenMBeanInfo cachedMBeanInfo;
/** The attribute mapping */
private Map attributeMapping;
/** The getters */
private Map getters;
/** The setters */
private Map setters;
/** The operatinns */
private Map operations;
/**
* Construct a DynamicMBean from the given implementation object
* and the passed management interface class.
*
* @param implementation the object implementing the mbean
* @param mbeanInterface the management interface of the mbean
* @exception IllegalArgumentException for a null implementation
* @exception NotCompliantMBeanException if the management interface
* does not follow the JMX design patterns or the implementation
* does not implement the interface
*/
public MXBeanDelegate(Object implementation, Class mbeanInterface) throws NotCompliantMBeanException
{
this.implementation = implementation;
this.mbeanInterface = mbeanInterface;
}
/**
* Construct a DynamicMBean from this object
* and the passed management interface class.
*
* Used in subclassing
*
* @param mbeanInterface the management interface of the mbean
* @exception NotCompliantMBeanException if the management interface
* does not follow the JMX design patterns or this
* does not implement the interface
*/
protected MXBeanDelegate(Class mbeanInterface) throws NotCompliantMBeanException
{
this.implementation = this;
this.mbeanInterface = mbeanInterface;
}
/**
* Retrieve the implementation object
*
* @return the implementation
*/
public Object getImplementation()
{
return implementation;
}
/**
* Replace the implementation object
*
* @todo make this work after the mbean is registered
* @param implementation the new implementation
* @exception IllegalArgumentException for a null parameter
* @exception NotCompliantMBeanException if the new implementation
* does not implement the interface supplied at
* construction
*/
public void setImplementation(Object implementation) throws NotCompliantMBeanException
{
if (implementation == null)
throw new IllegalArgumentException("Null implementation");
this.implementation = implementation;
}
/**
* Retrieve the implementation class
*
* @return the class of the implementation
*/
public Class getImplementationClass()
{
return implementation.getClass();
}
/**
* Retrieve the management interface
*
* @return the management interface
*/
public final Class getMBeanInterface()
{
return mbeanInterface;
}
public Object getAttribute(String attribute) throws AttributeNotFoundException, MBeanException, ReflectionException
{
try
{
OpenMBeanAttributeInfo attributeInfo = attributeMapping.get(attribute);
if (attributeInfo == null)
throw new AttributeNotFoundException(attribute);
MBeanAttributeInfo mbeanAttributeInfo = (MBeanAttributeInfo) attributeInfo;
if (mbeanAttributeInfo.isReadable() == false)
throw new AttributeNotFoundException("Attribute is not readable: " + attribute);
Method method = getters.get(attribute);
if (method == null)
throw new NoSuchMethodException("No method to get attribute: " + attribute);
Object result = method.invoke(implementation, new Object[0]);
return MXBeanUtils.construct(attributeInfo.getOpenType(), result, "Get attribute: " + attribute);
}
catch (Exception e)
{
JMException result = ExceptionHandler.handleException(e);
if (result instanceof AttributeNotFoundException)
throw (AttributeNotFoundException)result;
if (result instanceof MBeanException)
throw (MBeanException)result;
if (result instanceof ReflectionException)
throw (ReflectionException)result;
throw new MBeanException(e, "Cannot get attribute: " + attribute);
}
}
public void setAttribute(Attribute attribute) throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException, ReflectionException
{
try
{
String attributeName = attribute.getName();
OpenMBeanAttributeInfo attributeInfo = attributeMapping.get(attributeName);
if (attributeInfo == null)
throw new AttributeNotFoundException(attributeName);
MBeanAttributeInfo mbeanAttributeInfo = (MBeanAttributeInfo) attributeInfo;
if (mbeanAttributeInfo.isWritable() == false)
throw new AttributeNotFoundException("Attribute is not writable: " + attributeName);
Method method = setters.get(attributeName);
if (method == null)
throw new NoSuchMethodException("No method to set attribute: " + attribute);
Object value = MXBeanUtils.reconstruct(method.getGenericParameterTypes()[0], attribute.getValue(), method);
method.invoke(implementation, new Object[] { value });
}
catch (Exception e)
{
JMException result = ExceptionHandler.handleException(e);
if (result instanceof AttributeNotFoundException)
throw (AttributeNotFoundException)result;
if (result instanceof InvalidAttributeValueException)
throw (InvalidAttributeValueException)result;
if (result instanceof MBeanException)
throw (MBeanException)result;
if (result instanceof ReflectionException)
throw (ReflectionException)result;
throw new MBeanException(e, "Cannot set attribute: " + attribute);
}
}
public AttributeList getAttributes(String[] attributes)
{
try
{
AttributeList attrList = new AttributeList(attributes.length);
for (int i = 0; i < attributes.length; i++)
{
String name = attributes[i];
Object value = getAttribute(name);
attrList.add(new Attribute(name, value));
}
return attrList;
}
catch (Exception e)
{
JMException result = ExceptionHandler.handleException(e);
// Why is this not throwing the same exceptions as getAttribute(String)
throw new RuntimeException("Cannot get attributes", result);
}
}
public AttributeList setAttributes(AttributeList attributes)
{
AttributeList result = new AttributeList(attributes.size());
for (int i = 0; i < attributes.size(); ++i)
{
Attribute attr = (Attribute) attributes.get(i);
String name = attr.getName();
try
{
setAttribute(attr);
result.add(new Attribute(name, attr.getValue()));
}
catch (Throwable t)
{
JMException e = ExceptionHandler.handleException(t);
result.add(new Attribute(name, e));
}
}
return result;
}
public Object invoke(String actionName, Object[] params, String[] signature) throws MBeanException, ReflectionException
{
try
{
String signatureString = getSignatureString(actionName, signature);
Method method = operations.get(signatureString);
if (method == null)
throw new NoSuchMethodException("Cannot find method for operation: " + signatureString);
Object[] parameters = params;
if (params.length > 0)
{
parameters = new Object[params.length];
Type[] parameterTypes = method.getGenericParameterTypes();
for (int i = 0; i < parameters.length; ++i)
parameters[i] = MXBeanUtils.reconstruct(parameterTypes[i], params[i], method);
}
Object result = method.invoke(implementation, parameters);
if (result == null)
return null;
Type returnType = method.getGenericReturnType();
return MXBeanUtils.construct(returnType, result, method);
}
catch (Exception e)
{
JMException result = ExceptionHandler.handleException(e);
if (result instanceof MBeanException)
throw (MBeanException)result;
if (result instanceof ReflectionException)
throw (ReflectionException)result;
throw new MBeanException(e, "Cannot invoke: " + actionName);
}
}
public ObjectName preRegister(MBeanServer server, ObjectName name) throws Exception
{
return name;
}
public void postRegister(Boolean registrationDone)
{
}
public void preDeregister() throws Exception
{
}
public void postDeregister()
{
}
public MBeanInfo getMBeanInfo()
{
OpenMBeanInfo info = getCachedMBeanInfo();
if (info == null)
{
try
{
info = buildMBeanInfo();
cacheMBeanInfo(info);
}
catch (NotCompliantMBeanException e)
{
log.error("Unexcepted exception", e);
throw new IllegalStateException("Unexcepted exception " + e.toString());
}
}
return (MBeanInfo) info;
}
/**
* Retrieve the cached mbean info
*
* @return the cached mbean info
*/
public OpenMBeanInfo getCachedMBeanInfo()
{
return cachedMBeanInfo;
}
/**
* Sets the cached mbean info
*
* @param info the mbeaninfo to cache, can be null to erase the cache
*/
public void cacheMBeanInfo(OpenMBeanInfo info)
{
cachedMBeanInfo = info;
Map attributeMapping = new HashMap();
MBeanAttributeInfo[] attributes = info.getAttributes();
for (int i = 0; i < attributes.length; ++i)
{
OpenMBeanAttributeInfo attribute = (OpenMBeanAttributeInfo) attributes[i];
attributeMapping.put(attribute.getName(), attribute);
}
this.attributeMapping = attributeMapping;
try
{
HashMap getters = new HashMap();
HashMap setters = new HashMap();
HashMap operations = new HashMap();
Method[] methods = implementation.getClass().getMethods();
for (Method method : methods)
{
String methodName = method.getName();
Type[] signature = method.getGenericParameterTypes();
Type returnType = method.getGenericReturnType();
if (methodName.startsWith("set") &&
methodName.length() > 3 &&
signature.length == 1 &&
returnType == Void.TYPE)
{
String key = methodName.substring(3, methodName.length());
Method setter = setters.get(key);
if (setter != null && setter.getGenericParameterTypes()[0].equals(signature[0]) == false)
throw new RuntimeException("overloaded type for attribute set: " + key);
setters.put(key, method);
}
else if (methodName.startsWith("get") &&
methodName.length() > 3 &&
signature.length == 0 &&
returnType != Void.TYPE)
{
String key = methodName.substring(3, methodName.length());
Method getter = getters.get(key);
if (getter != null && getter.getName().startsWith("is"))
throw new RuntimeException("mixed use of get/is for attribute " + key);
getters.put(key, method);
}
else if (methodName.startsWith("is") &&
methodName.length() > 2 &&
signature.length == 0 &&
returnType == Boolean.TYPE)
{
String key = methodName.substring(2, methodName.length());
Method getter = getters.get(key);
if (getter != null && getter.getName().startsWith("get"))
throw new RuntimeException("mixed use of get/is for attribute " + key);
getters.put(key, method);
}
else
{
operations.put(getSignatureString(method), method);
}
}
this.getters = getters;
this.setters = setters;
this.operations = operations;
}
catch (RuntimeException e)
{
log.error("Error: ", e);
throw e;
}
catch (Error e)
{
log.error("Error: ", e);
throw e;
}
}
/**
* Builds a default MBeanInfo for this MBean, using the Management Interface specified for this MBean.
*
* While building the MBeanInfo, this method calls the customization hooks that make it possible for subclasses to
* supply their custom descriptions, parameter names, etc...
*
* @return the mbean info
* @throws NotCompliantMBeanException when not a valid mbean
*/
public OpenMBeanInfo buildMBeanInfo() throws NotCompliantMBeanException
{
if (implementation == null)
throw new IllegalArgumentException("Null implementation");
MXBeanMetaData metadata = new MXBeanMetaData(implementation, mbeanInterface);
return (OpenMBeanInfo) metadata.build();
}
/**
* Get a signature string for a method
*
* @param method the method
* @return the signature
*/
private String getSignatureString(Method method)
{
String name = method.getName();
Class[] signature = method.getParameterTypes();
StringBuilder buffer = new StringBuilder(512);
buffer.append(name);
buffer.append("(");
if (signature != null)
{
for (int i = 0; i < signature.length; i++)
{
buffer.append(signature[i].getName());
if (i < signature.length-1)
buffer.append(",");
}
}
buffer.append(")");
return buffer.toString();
}
/**
* Get a signature string for a method
*
* @param operation the operation
* @param signature the signature
* @return the signature
*/
private String getSignatureString(String operation, String[] signature)
{
StringBuilder buffer = new StringBuilder(512);
buffer.append(operation);
buffer.append("(");
if (signature != null)
{
for (int i = 0; i < signature.length; i++)
{
buffer.append(signature[i]);
if (i < signature.length-1)
buffer.append(",");
}
}
buffer.append(")");
return buffer.toString();
}
}