com.eucalyptus.component.ComponentMessages.java Source code

Introduction

Here is the source code for com.eucalyptus.component.ComponentMessages.java

Source

/*************************************************************************
 * Copyright 2009-2013 Eucalyptus Systems, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 3 of the License.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta
 * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need
 * additional information or have any questions.
 *
 * This file may incorporate work covered under the following copyright
 * and permission notice:
 *
 *   Software License Agreement (BSD License)
 *
 *   Copyright (c) 2008, Regents of the University of California
 *   All rights reserved.
 *
 *   Redistribution and use of this software in source and binary forms,
 *   with or without modification, are permitted provided that the
 *   following conditions are met:
 *
 *     Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *     Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer
 *     in the documentation and/or other materials provided with the
 *     distribution.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *   ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *   POSSIBILITY OF SUCH DAMAGE. USERS OF THIS SOFTWARE ACKNOWLEDGE
 *   THE POSSIBLE PRESENCE OF OTHER OPEN SOURCE LICENSED MATERIAL,
 *   COPYRIGHTED MATERIAL OR PATENTED MATERIAL IN THIS SOFTWARE,
 *   AND IF ANY SUCH MATERIAL IS DISCOVERED THE PARTY DISCOVERING
 *   IT MAY INFORM DR. RICH WOLSKI AT THE UNIVERSITY OF CALIFORNIA,
 *   SANTA BARBARA WHO WILL THEN ASCERTAIN THE MOST APPROPRIATE REMEDY,
 *   WHICH IN THE REGENTS' DISCRETION MAY INCLUDE, WITHOUT LIMITATION,
 *   REPLACEMENT OF THE CODE SO IDENTIFIED, LICENSING OF THE CODE SO
 *   IDENTIFIED, OR WITHDRAWAL OF THE CODE CAPABILITY TO THE EXTENT
 *   NEEDED TO COMPLY WITH ANY SUCH LICENSES OR RIGHTS.
 ************************************************************************/

package com.eucalyptus.component;

import java.lang.reflect.Modifier;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.NoSuchElementException;
import org.apache.log4j.Logger;
import com.eucalyptus.bootstrap.ServiceJarDiscovery;
import com.eucalyptus.component.annotation.ComponentMessage;
import com.eucalyptus.system.Ats;
import com.google.common.base.Predicates;
import com.google.common.collect.Maps;
import edu.ucsb.eucalyptus.msgs.BaseMessage;

public class ComponentMessages {
    private static Logger LOG = Logger.getLogger(ComponentMessages.class);
    private static final Map<Class<? extends BaseMessage>, Class<? extends ComponentId>> compIdMap = Maps
            .newHashMap();

    public static Collection<Class<? extends BaseMessage>> forComponent(ComponentId compId) {
        Class<? extends ComponentId> compIdClass = compId.getClass();
        if (!compIdMap.containsValue(compIdClass)) {
            return Collections.emptyList();
        } else {
            return Maps.filterValues((Map) compIdMap, Predicates.equalTo(compIdClass)).keySet();
        }
    }

    public static <T extends BaseMessage> Class<? extends ComponentId> lookup(T msg) {
        Class<?> msgType = Ats.inClassHierarchy(msg).findAncestor(ComponentMessage.class);
        if (!compIdMap.containsKey(msgType)) {
            throw new NoSuchElementException("No ComponentMessage with name: " + msgType);
        } else {
            return compIdMap.get(msgType);
        }
    }

    public static void register(Class<? extends BaseMessage> componentMsg) {
        @SuppressWarnings("unchecked")
        Class<? extends ComponentId> componentIdClass = Ats.from(componentMsg).get(ComponentMessage.class).value();
        compIdMap.put(componentMsg, componentIdClass);
    }

    public static class ComponentMessageDiscovery extends ServiceJarDiscovery {

        @Override
        public boolean processClass(Class candidate) throws Exception {
            if (BaseMessage.class.isAssignableFrom(candidate) && Ats.from(candidate).has(ComponentMessage.class)
                    && !Modifier.isAbstract(candidate.getModifiers())
                    && !Modifier.isInterface(candidate.getModifiers())) {
                try {
                    ComponentMessages.register(candidate);
                } catch (Exception ex) {
                    LOG.error(ex, ex);
                }
                return true;
            } else {
                return false;
            }
        }

        @Override
        public Double getPriority() {
            return 0.0d;
        }

    }

}