/*
* Copyright 2002-2005 the original author or authors.
*
* Licensed 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.springframework.jmx.export.metadata;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Iterator;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.metadata.Attributes;
import org.springframework.util.Assert;
/**
* Implementation of the <code>JmxAttributeSource</code> interface that
* reads metadata via Spring's <code>Attributes</code> abstraction.
*
* <p>Typically used for reading in source-level attributes via
* Commons Attributes.
*
* @author Rob Harrop
* @since 1.2
* @see org.springframework.metadata.Attributes
* @see org.springframework.metadata.commons.CommonsAttributes
*/
public class AttributesJmxAttributeSource implements JmxAttributeSource, InitializingBean {
/**
* Underlying Attributes implementation that we're using.
*/
private Attributes attributes;
/**
* Create a new AttributesJmxAttributeSource.
* @see #setAttributes
*/
public AttributesJmxAttributeSource() {
}
/**
* Create a new AttributesJmxAttributeSource.
* @param attributes the Attributes implementation to use
* @see org.springframework.metadata.commons.CommonsAttributes
*/
public AttributesJmxAttributeSource(Attributes attributes) {
if (attributes == null) {
throw new IllegalArgumentException("Attributes is required");
}
this.attributes = attributes;
}
/**
* Set the Attributes implementation to use.
* @see org.springframework.metadata.commons.CommonsAttributes
*/
public void setAttributes(Attributes attributes) {
this.attributes = attributes;
}
public void afterPropertiesSet() {
if (this.attributes == null) {
throw new IllegalArgumentException("'attributes' is required");
}
}
/**
* If the specified class has a <code>ManagedResource</code> attribute,
* then it is returned. Otherwise returns null.
* @param clazz the class to read the attribute data from
* @return the attribute, or <code>null</code> if not found
* @throws InvalidMetadataException if more than one attribute exists
*/
public ManagedResource getManagedResource(Class clazz) {
Assert.notNull(this.attributes, "'attributes' is required");
Collection attrs = this.attributes.getAttributes(clazz, ManagedResource.class);
if (attrs.isEmpty()) {
return null;
}
else if (attrs.size() == 1) {
return (ManagedResource) attrs.iterator().next();
}
else {
throw new InvalidMetadataException("A Class can have only one ManagedResource attribute");
}
}
/**
* If the specified method has a <code>ManagedAttribute</code> attribute,
* then it is returned. Otherwise returns null.
* @param method the method to read the attribute data from
* @return the attribute, or <code>null</code> if not found
* @throws InvalidMetadataException if more than one attribute exists,
* or if the supplied method does not represent a JavaBean property
*/
public ManagedAttribute getManagedAttribute(Method method) throws InvalidMetadataException {
Assert.notNull(this.attributes, "'attributes' is required");
PropertyDescriptor pd = BeanUtils.findPropertyForMethod(method);
if (pd == null) {
throw new InvalidMetadataException(
"The ManagedAttribute attribute is only valid for JavaBean properties: " +
"use ManagedOperation for methods");
}
Collection attrs = this.attributes.getAttributes(method, ManagedAttribute.class);
if (attrs.isEmpty()) {
return null;
}
else if (attrs.size() == 1) {
return (ManagedAttribute) attrs.iterator().next();
}
else {
throw new InvalidMetadataException("A Method can have only one ManagedAttribute attribute");
}
}
/**
* If the specified method has a <code>ManagedOperation</code> attribute,
* then it is returned. Otherwise return null.
* @param method the method to read the attribute data from
* @return the attribute, or <code>null</code> if not found
* @throws InvalidMetadataException if more than one attribute exists,
* or if the supplied method represents a JavaBean property
*/
public ManagedOperation getManagedOperation(Method method) {
Assert.notNull(this.attributes, "'attributes' is required");
PropertyDescriptor pd = BeanUtils.findPropertyForMethod(method);
if (pd != null) {
throw new InvalidMetadataException(
"The ManagedOperation attribute is not valid for JavaBean properties: " +
"use ManagedAttribute instead");
}
Collection attrs = this.attributes.getAttributes(method, ManagedOperation.class);
if (attrs.isEmpty()) {
return null;
}
else if (attrs.size() == 1) {
return (ManagedOperation) attrs.iterator().next();
}
else {
throw new InvalidMetadataException("A Method can have only one ManagedAttribute attribute");
}
}
/**
* If the specified method has <code>ManagedOperationParameter</code> attributes,
* then these are returned, otherwise a zero length array is returned.
* @param method the method to get the managed operation parameters for
* @return the array of ManagedOperationParameter objects
* @throws InvalidMetadataException if the number of ManagedOperationParameter
* attributes does not match the number of parameters in the method
*/
public ManagedOperationParameter[] getManagedOperationParameters(Method method)
throws InvalidMetadataException {
Assert.notNull(this.attributes, "'attributes' is required");
Collection attrs = this.attributes.getAttributes(method, ManagedOperationParameter.class);
if (attrs.size() == 0) {
return new ManagedOperationParameter[0];
}
else if (attrs.size() != method.getParameterTypes().length) {
throw new InvalidMetadataException(
"Method [" + method + "] has an incorrect number of ManagedOperationParameters specified");
}
else {
ManagedOperationParameter[] params = new ManagedOperationParameter[attrs.size()];
for (Iterator it = attrs.iterator(); it.hasNext();) {
ManagedOperationParameter param = (ManagedOperationParameter) it.next();
if (param.getIndex() < 0 || param.getIndex() >= params.length) {
throw new InvalidMetadataException(
"ManagedOperationParameter index for [" + param.getName() + "] is out of bounds");
}
params[param.getIndex()] = param;
}
return params;
}
}
/**
* If the specified has {@link ManagedNotification} attributes these are returned, otherwise
* a zero-length array is returned.
*/
public ManagedNotification[] getManagedNotifications(Class clazz) {
Assert.notNull(this.attributes, "'attributes' is required");
Collection attrs = this.attributes.getAttributes(clazz, ManagedNotification.class);
return attrs.isEmpty() ? new ManagedNotification[0] : (ManagedNotification[]) attrs.toArray(new ManagedNotification[attrs.size()]);
}
}