/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.harmony.lang.management;
import java.lang.reflect.Method;
import javax.management.Attribute;
import javax.management.AttributeList;
import javax.management.AttributeNotFoundException;
import javax.management.DynamicMBean;
import javax.management.InvalidAttributeValueException;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanException;
import javax.management.MBeanInfo;
import javax.management.MBeanOperationInfo;
import javax.management.MBeanParameterInfo;
import javax.management.ReflectionException;
import org.apache.harmony.lang.management.internal.nls.Messages;
/**
* Abstract implementation of the {@link DynamicMBean} interface that provides
* behaviour required by a dynamic MBean. This class is subclassed by all of the
* concrete MXBean types in this package.
*/
public abstract class DynamicMXBeanImpl implements DynamicMBean {
protected MBeanInfo info;
/**
* @param info
*/
protected void setMBeanInfo(MBeanInfo info) {
this.info = info;
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#getAttributes(java.lang.String[])
*/
public AttributeList getAttributes(String[] attributes) {
AttributeList result = new AttributeList();
for (int i = 0; i < attributes.length; i++) {
try {
Object value = getAttribute(attributes[i]);
result.add(new Attribute(attributes[i], value));
} catch (Exception e) {
// It is alright if the returned AttributeList is smaller in
// size than the length of the input array.
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
}
}// end for
return result;
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#setAttributes(javax.management.AttributeList)
*/
public AttributeList setAttributes(AttributeList attributes) {
AttributeList result = new AttributeList();
for (int i = 0; i < attributes.size(); i++) {
Attribute attrib = (Attribute) attributes.get(i);
String attribName = null;
Object attribVal = null;
try {
this.setAttribute(attrib);
attribName = attrib.getName();
// Note that the below getAttribute call will throw an
// AttributeNotFoundException if the named attribute is not
// readable for this bean. This is perfectly alright - the set
// has worked as requested - it just means that the caller
// does not get this information returned to them in the
// result AttributeList.
attribVal = getAttribute(attribName);
result.add(new Attribute(attribName, attribVal));
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
}
}// end for
return result;
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#getMBeanInfo()
*/
public MBeanInfo getMBeanInfo() {
return info;
}
/**
* Simple enumeration of the different kinds of access that may be required
* of a dynamic MBean attribute.
*/
enum AttributeAccessType {
READING, WRITING
};
/**
* Tests to see if this <code>DynamicMXBean</code> has an attribute with
* the name <code>attributeName</code>. If the test is passed, the
* {@link MBeanAttributeInfo}representing the attribute is returned.
*
* @param attributeName
* the name of the attribute being queried
* @param access
* an {@link AttributeAccessType}indication of whether the
* caller is looking for a readable or writable attribute.
* @return if the named attribute exists and is readable or writable
* (depending on what was specified in <code>access</code>, an
* instance of <code>MBeanAttributeInfo</code> that describes the
* attribute, otherwise <code>null</code>.
*/
protected MBeanAttributeInfo getPresentAttribute(String attributeName,
AttributeAccessType access) {
MBeanAttributeInfo[] attribs = info.getAttributes();
MBeanAttributeInfo result = null;
for (int i = 0; i < attribs.length; i++) {
MBeanAttributeInfo attribInfo = attribs[i];
if (attribInfo.getName().equals(attributeName)) {
if (access.equals(AttributeAccessType.READING)) {
if (attribInfo.isReadable()) {
result = attribInfo;
break;
}
} else {
if (attribInfo.isWritable()) {
result = attribInfo;
break;
}
}
}// end if
}// end for
return result;
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#getAttribute(java.lang.String)
*/
public Object getAttribute(String attribute)
throws AttributeNotFoundException, MBeanException,
ReflectionException {
Object result = null;
Method getterMethod = null;
MBeanAttributeInfo attribInfo = getPresentAttribute(attribute,
AttributeAccessType.READING);
if (attribInfo == null) {
//lm.0A=No such attribute : {0}
throw new AttributeNotFoundException(Messages.getString("lm.0A", attribute)); //$NON-NLs-1$
}
try {
String getterPrefix = attribInfo.isIs() ? "is" : "get";
getterMethod = this.getClass().getMethod(getterPrefix + attribute,
(Class[]) null);
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new ReflectionException(e);
}
String realReturnType = getterMethod.getReturnType().getName();
String openReturnType = attribInfo.getType();
result = invokeMethod(getterMethod, (Object[]) null);
try {
if (!realReturnType.equals(openReturnType)) {
result = ManagementUtils
.convertToOpenType(result, Class
.forName(openReturnType), Class
.forName(realReturnType));
}// end if conversion necessary
} catch (ClassNotFoundException e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new MBeanException(e);
}
return result;
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#setAttribute(javax.management.Attribute)
*/
public void setAttribute(Attribute attribute)
throws AttributeNotFoundException, InvalidAttributeValueException,
MBeanException, ReflectionException {
// In Java 5.0 platform MXBeans the following applies for all
// attribute setter methods :
// 1. no conversion to open MBean types necessary
// 2. all setter arguments are single value (i.e. not array or
// collection types).
// 3. all return null
Class<?> argType = null;
// Validate the attribute
MBeanAttributeInfo attribInfo = getPresentAttribute(
attribute.getName(), AttributeAccessType.WRITING);
if (attribInfo == null) {
//lm.0A=No such attribute : {0}
throw new AttributeNotFoundException(Messages.getString("lm.0A", attribute)); //$NON-NLs-1$
}
try {
// Validate supplied parameter is of the expected type
argType = ManagementUtils.getClassMaybePrimitive(attribInfo
.getType());
} catch (ClassNotFoundException e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new ReflectionException(e);
}
if (argType.isPrimitive()) {
if (!ManagementUtils.isWrapperClass(
attribute.getValue().getClass(), argType)) {
//lm.0B= {0} is a {1} attribute
throw new InvalidAttributeValueException(Messages.getString("lm.0B", attribInfo.getName(), attribInfo.getType())); //$NON-NLS-1$
}
} else if (!argType.equals(attribute.getValue().getClass())) {
//lm.0B= {0} is a {1} attribute
throw new InvalidAttributeValueException(Messages.getString("lm.0B", attribInfo.getName(), attribInfo.getType())); //$NON-NLS-1$
}
Method setterMethod = null;
try {
setterMethod = this.getClass().getMethod(
"set" + attribute.getName(), new Class[] { argType });
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new ReflectionException(e);
}
invokeMethod(setterMethod, attribute.getValue());
try {
setterMethod.invoke(this, attribute.getValue());
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
Throwable root = e.getCause();
if (root instanceof RuntimeException) {
throw (RuntimeException) root;
} else {
throw new MBeanException((Exception) root);
}// end else
}// end catch
}
/*
* (non-Javadoc)
*
* @see javax.management.DynamicMBean#invoke(java.lang.String,
* java.lang.Object[], java.lang.String[])
*/
public Object invoke(String actionName, Object[] params, String[] signature)
throws MBeanException, ReflectionException {
Object result = null;
// If null is passed in for the signature argument (if invoking a
// method with no args for instance) then avoid any NPEs by working
// with a zero length String array instead.
String[] localSignature = signature;
if (localSignature == null) {
localSignature = new String[0];
}
// Validate that we have the named action
MBeanOperationInfo opInfo = getPresentOperation(actionName,
localSignature);
if (opInfo == null) {
//lm.0C=No such operation : {0}
throw new ReflectionException( new NoSuchMethodException (actionName), Messages.getString("lm.0C", actionName)); //$NON-NLS-1$
}
// For Java 5.0 platform MXBeans, no conversion
// to open MBean types is necessary for any of the arguments.
// i.e. they are all simple types.
Method operationMethod = null;
try {
Class<?>[] argTypes = new Class[localSignature.length];
for (int i = 0; i < localSignature.length; i++) {
argTypes[i] = ManagementUtils
.getClassMaybePrimitive(localSignature[i]);
}// end for
operationMethod = this.getClass().getMethod(actionName, argTypes);
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new ReflectionException(e);
}
String realReturnType = operationMethod.getReturnType().getName();
String openReturnType = opInfo.getReturnType();
result = invokeMethod(operationMethod, params);
try {
if (!realReturnType.equals(openReturnType)) {
result = ManagementUtils
.convertToOpenType(result, Class
.forName(openReturnType), Class
.forName(realReturnType));
}
} catch (ClassNotFoundException e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
throw new MBeanException(e);
}// end catch
return result;
}
/**
* Tests to see if this <code>DynamicMXBean</code> has an operation with
* the name <code>actionName</code>. If the test is passed, the
* {@link MBeanOperationInfo}representing the operation is returned to the
* caller.
*
* @param actionName
* the name of a possible method on this
* <code>DynamicMXBean</code>
* @param signature
* the list of parameter types for the named operation in the
* correct order
* @return if the named operation exists, an instance of
* <code>MBeanOperationInfo</code> that describes the operation,
* otherwise <code>null</code>.
*/
protected MBeanOperationInfo getPresentOperation(String actionName,
String[] signature) {
MBeanOperationInfo[] operations = info.getOperations();
MBeanOperationInfo result = null;
for (int i = 0; i < operations.length; i++) {
MBeanOperationInfo opInfo = operations[i];
if (opInfo.getName().equals(actionName)) {
// Do parameter numbers match ?
if (signature.length == opInfo.getSignature().length) {
// Do parameter types match ?
boolean match = true;
MBeanParameterInfo[] parameters = opInfo.getSignature();
for (int j = 0; j < parameters.length; j++) {
MBeanParameterInfo paramInfo = parameters[j];
if (!paramInfo.getType().equals(signature[j])) {
match = false;
break;
}
}// end for all parameters
if (match) {
result = opInfo;
break;
}
}// end if parameter counts match
}// end if operation names match
}// end for all operations
return result;
}
/**
* @param params
* @param operationMethod
* @return the result of the reflective method invocation
* @throws MBeanException
*/
private Object invokeMethod(Method operationMethod, Object... params)
throws MBeanException {
Object result = null;
try {
result = operationMethod.invoke(this, params);
} catch (Exception e) {
if (ManagementUtils.VERBOSE_MODE) {
e.printStackTrace(System.err);
}// end if
Throwable root = e.getCause();
if (root instanceof RuntimeException) {
throw (RuntimeException) root;
} else {
throw new MBeanException((Exception) root);
}// end else
}// end catch
return result;
}
}