| 1 | /** |
| 2 | * Copyright (C) 2006 NetMind Consulting Bt. |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 3 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with this library; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | */ |
| 18 | |
| 19 | package hu.netmind.beankeeper.service.impl; |
| 20 | |
| 21 | import hu.netmind.beankeeper.service.StoreContext; |
| 22 | import hu.netmind.beankeeper.service.Service; |
| 23 | import hu.netmind.beankeeper.service.ServiceFactory; |
| 24 | import hu.netmind.beankeeper.common.StoreException; |
| 25 | import java.util.*; |
| 26 | import java.lang.reflect.Field; |
| 27 | import org.apache.log4j.Logger; |
| 28 | |
| 29 | /** |
| 30 | * This is the context for all the services. Basically a mini |
| 31 | * dependency injection engine. |
| 32 | * @author Brautigam Robert |
| 33 | * @version Revision: $Revision$ |
| 34 | */ |
| 35 | public class StoreContextImpl implements StoreContext |
| 36 | { |
| 37 | private static final String[] SERVICES = |
| 38 | { |
| 39 | "hu.netmind.beankeeper.event.impl.EventDispatcherImpl", |
| 40 | "hu.netmind.beankeeper.management.impl.ManagementTrackerImpl", |
| 41 | "hu.netmind.beankeeper.config.impl.ConfigurationTrackerImpl", |
| 42 | "hu.netmind.beankeeper.logging.impl.SnapshotLoggerImpl", |
| 43 | "hu.netmind.beankeeper.logging.impl.AggregatorLoggerImpl", |
| 44 | "hu.netmind.beankeeper.db.impl.DatabaseFactory", |
| 45 | "hu.netmind.beankeeper.transaction.impl.InternalTransactionTrackerImpl", |
| 46 | "hu.netmind.beankeeper.node.impl.NodeManagerImpl", |
| 47 | "hu.netmind.beankeeper.serial.impl.SerialTrackerImpl", |
| 48 | "hu.netmind.beankeeper.operation.impl.OperationTrackerImpl", |
| 49 | "hu.netmind.beankeeper.transaction.impl.TransactionTrackerImpl", |
| 50 | "hu.netmind.beankeeper.type.impl.TypeHandlerTrackerImpl", |
| 51 | "hu.netmind.beankeeper.model.impl.ClassTrackerImpl", |
| 52 | "hu.netmind.beankeeper.schema.impl.SchemaManagerImpl", |
| 53 | "hu.netmind.beankeeper.object.impl.ObjectTrackerImpl", |
| 54 | "hu.netmind.beankeeper.cache.impl.MinimalResultsCache", |
| 55 | "hu.netmind.beankeeper.query.impl.QueryServiceImpl", |
| 56 | "hu.netmind.beankeeper.modification.impl.ModificationTrackerImpl", |
| 57 | "hu.netmind.beankeeper.lock.impl.LockTrackerImpl", |
| 58 | "hu.netmind.beankeeper.type.impl.DefaultHandlersService", |
| 59 | "hu.netmind.beankeeper.store.impl.StoreServiceImpl", |
| 60 | }; |
| 61 | private static final Logger logger = Logger.getLogger(StoreContext.class); |
| 62 | |
| 63 | private Map parameters = new HashMap(); |
| 64 | private Map<String,Service> services = new HashMap<String,Service>(); |
| 65 | private List<Service> initOrder = new ArrayList<Service>(); |
| 66 | private Thread shutdownHook = null; |
| 67 | private boolean shutdownRunning = false; |
| 68 | private boolean released = false; |
| 69 | |
| 70 | /** |
| 71 | * Initialize this context. This method populates the services |
| 72 | * and registers the shutdown hook. |
| 73 | */ |
| 74 | public void init(Map parameters) |
| 75 | { |
| 76 | logger.debug("initializing store context with parameters: "+parameters); |
| 77 | this.parameters.putAll(parameters); |
| 78 | // First, insert self as a service |
| 79 | services.put(StoreContext.class.getName(),this); |
| 80 | // Initialize dependencies as given in the list |
| 81 | logger.debug("initializing services"); |
| 82 | for ( String serviceClassName : SERVICES ) |
| 83 | { |
| 84 | try |
| 85 | { |
| 86 | // Get the implementation class |
| 87 | Class serviceClass = Class.forName(serviceClassName); |
| 88 | // Initialize the service |
| 89 | if ( logger.isDebugEnabled() ) |
| 90 | logger.debug("initializing service: "+serviceClassName); |
| 91 | // Creating and adding the service |
| 92 | Service service = (Service) serviceClass.newInstance(); |
| 93 | // Inject & Initialize |
| 94 | injectServices(service); |
| 95 | service.init(parameters); |
| 96 | // If this is a factory, then create real service object |
| 97 | if ( service instanceof ServiceFactory ) |
| 98 | { |
| 99 | Service realService = ((ServiceFactory) service).getService(); |
| 100 | injectServices(realService); |
| 101 | realService.init(parameters); |
| 102 | service.release(); |
| 103 | service = realService; |
| 104 | serviceClass = realService.getClass(); |
| 105 | } |
| 106 | // Initialization ok, add |
| 107 | Set<Class> serviceInterfaces = getServiceInterfaces(serviceClass); |
| 108 | for ( Class serviceInterface : serviceInterfaces ) |
| 109 | services.put(serviceInterface.getName(),service); |
| 110 | initOrder.add(service); |
| 111 | if ( logger.isDebugEnabled() ) |
| 112 | logger.debug("initialized service '"+serviceClass.getName()+"' which implements: "+serviceInterfaces); |
| 113 | } catch ( StoreException e ) { |
| 114 | throw e; |
| 115 | } catch ( Exception e ) { |
| 116 | throw new StoreException("could not initialize service: "+serviceClassName,e); |
| 117 | } |
| 118 | } |
| 119 | // Proper shutdown |
| 120 | shutdownHook = new Thread(new ShutdownProcess()); |
| 121 | Runtime.getRuntime().addShutdownHook(shutdownHook); |
| 122 | // Ok |
| 123 | logger.debug("store initialization complete, good luck"); |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * Determine all the interfaces a service provides. |
| 128 | */ |
| 129 | private Set<Class> getServiceInterfaces(Class serviceClass) |
| 130 | { |
| 131 | Class originalClass = serviceClass; |
| 132 | // Find and register all service interfaces |
| 133 | Set<Class> result = new HashSet<Class>(); |
| 134 | while ( serviceClass != null ) |
| 135 | { |
| 136 | Class[] interfaces = serviceClass.getInterfaces(); |
| 137 | for ( Class interfaceClass : interfaces ) |
| 138 | { |
| 139 | if ( Service.class.isAssignableFrom(interfaceClass) ) |
| 140 | result.add(interfaceClass); |
| 141 | } |
| 142 | serviceClass = serviceClass.getSuperclass(); |
| 143 | } |
| 144 | if ( logger.isDebugEnabled() ) |
| 145 | logger.debug("service '"+originalClass+"' had following interfaces: "+result); |
| 146 | return result; |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * Inject services into the object given. |
| 151 | */ |
| 152 | public void injectServices(Object obj) |
| 153 | { |
| 154 | Class objectClass = obj.getClass(); |
| 155 | while ( objectClass != null ) |
| 156 | { |
| 157 | Field[] fields = objectClass.getDeclaredFields(); |
| 158 | for ( Field field : fields ) |
| 159 | { |
| 160 | // Inject a single field |
| 161 | if ( Service.class.isAssignableFrom(field.getType()) ) |
| 162 | { |
| 163 | Service service = getService(field.getType().getName()); |
| 164 | if ( service == null ) |
| 165 | throw new StoreException("missing service for field: "+field.getType().getName()+", into: "+obj+", class: "+objectClass); |
| 166 | try |
| 167 | { |
| 168 | field.setAccessible(true); |
| 169 | field.set(obj,service); |
| 170 | } catch ( IllegalAccessException e ) { |
| 171 | throw new StoreException("no permission to inject service to: "+field,e); |
| 172 | } |
| 173 | } |
| 174 | } |
| 175 | objectClass = objectClass.getSuperclass(); |
| 176 | } |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * Return whether the given service is available. |
| 181 | * @return True if service is available. |
| 182 | */ |
| 183 | public boolean hasService(String name) |
| 184 | { |
| 185 | return getService(name) != null; |
| 186 | } |
| 187 | |
| 188 | /** |
| 189 | * Get the service under the given name. |
| 190 | * @param name The name of the service to return. |
| 191 | * @return The service under the given name. |
| 192 | */ |
| 193 | public Service getService(String name) |
| 194 | { |
| 195 | return services.get(name); |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * Close this context and release all allocated resources. |
| 200 | */ |
| 201 | public void release() |
| 202 | { |
| 203 | if ( released ) |
| 204 | return; // Don't release twice |
| 205 | released = true; |
| 206 | // Call release on all services in reverse order of initialization |
| 207 | List<Service> closeOrder = new ArrayList<Service>(initOrder); |
| 208 | Collections.reverse(closeOrder); |
| 209 | for ( Service service : closeOrder ) |
| 210 | { |
| 211 | try |
| 212 | { |
| 213 | service.release(); |
| 214 | } catch ( Exception e ) { |
| 215 | logger.error("error while releasing service: "+service,e); |
| 216 | } |
| 217 | } |
| 218 | // Clear everything |
| 219 | initOrder = new ArrayList<Service>(); |
| 220 | services = new HashMap<String,Service>(); |
| 221 | // Remove shutdown hook when complete |
| 222 | if ( ! shutdownRunning ) |
| 223 | Runtime.getRuntime().removeShutdownHook(shutdownHook); // Do not run twice |
| 224 | } |
| 225 | |
| 226 | /** |
| 227 | * Get the parameters this context was created with. |
| 228 | */ |
| 229 | public Map getParameters() |
| 230 | { |
| 231 | return parameters; |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * This is a shutdown logic, which simply calls <code>close()</code> |
| 236 | * when the JVM exists. |
| 237 | */ |
| 238 | private class ShutdownProcess implements Runnable |
| 239 | { |
| 240 | public void run() |
| 241 | { |
| 242 | shutdownRunning=true; |
| 243 | release(); |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | } |
| 248 | |
| 249 | |