001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.activemq.console.filter;
018    
019    import javax.management.Attribute;
020    import javax.management.AttributeList;
021    import javax.management.InstanceNotFoundException;
022    import javax.management.IntrospectionException;
023    import javax.management.MBeanAttributeInfo;
024    import javax.management.MBeanServerConnection;
025    import javax.management.ObjectInstance;
026    import javax.management.ObjectName;
027    import javax.management.ReflectionException;
028    import java.io.IOException;
029    import java.util.ArrayList;
030    import java.util.Collection;
031    import java.util.Iterator;
032    import java.util.List;
033    import java.util.Set;
034    
035    public class MBeansAttributeQueryFilter extends AbstractQueryFilter {
036        public static final String KEY_OBJECT_NAME_ATTRIBUTE = "Attribute:ObjectName:";
037    
038        private MBeanServerConnection jmxConnection;
039        private Set attribView;
040    
041        /**
042         * Create an mbean attributes query filter that is able to select specific
043         * mbean attributes based on the object name to get.
044         * 
045         * @param jmxConnection - JMX connection to use.
046         * @param attribView - the attributes to extract
047         * @param next - the next query filter
048         */
049        public MBeansAttributeQueryFilter(MBeanServerConnection jmxConnection, Set attribView, MBeansObjectNameQueryFilter next) {
050            super(next);
051            this.jmxConnection = jmxConnection;
052            this.attribView = attribView;
053        }
054    
055        /**
056         * Filter the query by retrieving the attributes specified, this will modify
057         * the collection to a list of AttributeList
058         * 
059         * @param queries - query list
060         * @return List of AttributeList, which includes the ObjectName, which has a
061         *         key of MBeansAttributeQueryFilter.KEY_OBJECT_NAME_ATTRIBUTE
062         * @throws Exception
063         */
064        public List query(List queries) throws Exception {
065            return getMBeanAttributesCollection(next.query(queries));
066        }
067    
068        /**
069         * Retrieve the specified attributes of the mbean
070         * 
071         * @param result - collection of ObjectInstances and/or ObjectNames
072         * @return List of AttributeList
073         * @throws IOException
074         * @throws ReflectionException
075         * @throws InstanceNotFoundException
076         * @throws NoSuchMethodException
077         */
078        protected List getMBeanAttributesCollection(Collection result) throws IOException, ReflectionException, InstanceNotFoundException, NoSuchMethodException, IntrospectionException {
079            List mbeansCollection = new ArrayList();
080    
081            for (Iterator i = result.iterator(); i.hasNext();) {
082                Object mbean = i.next();
083                if (mbean instanceof ObjectInstance) {
084                    try {
085                        mbeansCollection.add(getMBeanAttributes(((ObjectInstance)mbean).getObjectName(), attribView));
086                    } catch (InstanceNotFoundException ignore) {
087                        // mbean could have been deleted in the meantime
088                    }
089                } else if (mbean instanceof ObjectName) {
090                    try {
091                        mbeansCollection.add(getMBeanAttributes((ObjectName)mbean, attribView));
092                    } catch (InstanceNotFoundException ignore) {
093                        // mbean could have been deleted in the meantime
094                    }
095                } else {
096                    throw new NoSuchMethodException("Cannot get the mbean attributes for class: " + mbean.getClass().getName());
097                }
098            }
099    
100            return mbeansCollection;
101        }
102    
103        /**
104         * Retrieve the specified attributes of the mbean
105         * 
106         * @param obj - mbean ObjectInstance
107         * @param attrView - list of attributes to retrieve
108         * @return AttributeList for the mbean
109         * @throws ReflectionException
110         * @throws InstanceNotFoundException
111         * @throws IOException
112         */
113        protected AttributeList getMBeanAttributes(ObjectInstance obj, Set attrView) throws ReflectionException, InstanceNotFoundException, IOException, IntrospectionException {
114            return getMBeanAttributes(obj.getObjectName(), attrView);
115        }
116    
117        /**
118         * Retrieve the specified attributes of the mbean
119         * 
120         * @param objName - mbean ObjectName
121         * @param attrView - list of attributes to retrieve
122         * @return AttributeList for the mbean
123         * @throws IOException
124         * @throws ReflectionException
125         * @throws InstanceNotFoundException
126         */
127        protected AttributeList getMBeanAttributes(ObjectName objName, Set attrView) throws IOException, ReflectionException, InstanceNotFoundException, IntrospectionException {
128            // If no attribute view specified, get all attributes
129            String[] attribs;
130            if (attrView == null || attrView.isEmpty()) {
131                MBeanAttributeInfo[] infos = jmxConnection.getMBeanInfo(objName).getAttributes();
132                attribs = new String[infos.length];
133    
134                for (int i = 0; i < infos.length; i++) {
135                    if (infos[i].isReadable()) {
136                        attribs[i] = infos[i].getName();
137                    }
138                }
139    
140                // Get selected attributes
141            } else {
142    
143                attribs = new String[attrView.size()];
144                int count = 0;
145                for (Iterator i = attrView.iterator(); i.hasNext();) {
146                    attribs[count++] = (String)i.next();
147                }
148            }
149    
150            AttributeList attribList = jmxConnection.getAttributes(objName, attribs);
151    
152            attribList.add(0, new Attribute(KEY_OBJECT_NAME_ATTRIBUTE, objName));
153    
154            return attribList;
155        }
156    }