diff options
Diffstat (limited to 'sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core')
7 files changed, 690 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java new file mode 100644 index 0000000000..48f240559c --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java @@ -0,0 +1,184 @@ +/* + * 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.tuscany.sca.core; + +import java.io.IOException; +import java.lang.reflect.Constructor; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Modifier; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Map; +import java.util.Set; + +import org.apache.tuscany.sca.extensibility.ServiceDiscovery; + +/** + * Default implementation of a registry to hold all the Tuscany core extension + * points. As the point of contact for all extension artifacts this registry + * allows loaded extensions to find all other parts of the system and register + * themselves appropriately. + * + * @version $Rev$ $Date$ + */ +public class DefaultExtensionPointRegistry implements ExtensionPointRegistry { + private Map<Class<?>, Object> extensionPoints = new HashMap<Class<?>, Object>(); + + /** + * Constructs a new registry. + */ + public DefaultExtensionPointRegistry() { + } + + /** + * Add an extension point to the registry. This default implementation + * stores extensions against the interfaces that they implement. + * + * @param extensionPoint The instance of the extension point + * + * @throws IllegalArgumentException if extensionPoint is null + */ + public void addExtensionPoint(Object extensionPoint) { + if (extensionPoint == null) { + throw new IllegalArgumentException("Cannot register null as an ExtensionPoint"); + } + + Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass()); + for (Class<?> i : interfaces) { + extensionPoints.put(i, extensionPoint); + } + } + + private Constructor<?> getConstructor(Constructor<?>[] constructors, Class<?>[] paramTypes) { + for (Constructor<?> c : constructors) { + Class<?>[] types = c.getParameterTypes(); + if (c.getParameterTypes().length == paramTypes.length) { + boolean found = true; + for (int i = 0; i < types.length; i++) { + if (types[i] != paramTypes[i]) { + found = false; + break; + } + } + if (found) { + return c; + } + } + } + return null; + } + + /** + * Get the extension point by the interface that it implements + * + * @param extensionPointType The lookup key (extension point interface) + * @return The instance of the extension point + * + * @throws IllegalArgumentException if extensionPointType is null + */ + public <T> T getExtensionPoint(Class<T> extensionPointType) { + if (extensionPointType == null) { + throw new IllegalArgumentException("Cannot lookup ExtensionPoint of type null"); + } + + Object extensionPoint = extensionPoints.get(extensionPointType); + if (extensionPoint == null) { + + // Dynamically load an extension point class declared under META-INF/services + try { + Class<?> extensionPointClass = + ServiceDiscovery.getInstance().loadFirstServiceClass(extensionPointType); + if (extensionPointClass != null) { + // Construct the extension point + Constructor<?>[] constructors = extensionPointClass.getConstructors(); + Constructor<?> constructor = getConstructor(constructors, new Class<?>[] {ExtensionPointRegistry.class}); + if (constructor != null) { + extensionPoint = constructor.newInstance(this); + } else { + constructor = getConstructor(constructors, new Class<?>[] {}); + if (constructor != null) { + extensionPoint = constructor.newInstance(); + } else { + throw new IllegalArgumentException( + "No valid constructor is found for " + extensionPointClass); + } + } + + // Cache the loaded extension point + addExtensionPoint(extensionPoint); + } + } catch (InvocationTargetException e) { + throw new IllegalArgumentException(e); + } catch (IOException e) { + throw new IllegalArgumentException(e); + } catch (ClassNotFoundException e) { + throw new IllegalArgumentException(e); + } catch (InstantiationException e) { + throw new IllegalArgumentException(e); + } catch (IllegalAccessException e) { + throw new IllegalArgumentException(e); + } + } + return extensionPointType.cast(extensionPoint); + } + + /** + * Remove an extension point based on the interface that it implements + * + * @param extensionPoint The extension point to remove + * + * @throws IllegalArgumentException if extensionPoint is null + */ + public void removeExtensionPoint(Object extensionPoint) { + if (extensionPoint == null) { + throw new IllegalArgumentException("Cannot remove null as an ExtensionPoint"); + } + + Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass()); + for (Class<?> i : interfaces) { + extensionPoints.remove(i); + } + } + + /** + * Returns the set of interfaces implemented by the given class and its + * ancestors or a blank set if none + */ + private static Set<Class<?>> getAllInterfaces(Class<?> clazz) { + Set<Class<?>> implemented = new HashSet<Class<?>>(); + getAllInterfaces(clazz, implemented); + return implemented; + } + + private static void getAllInterfaces(Class<?> clazz, Set<Class<?>> implemented) { + Class<?>[] interfaces = clazz.getInterfaces(); + for (Class<?> interfaze : interfaces) { + if (Modifier.isPublic(interfaze.getModifiers())) { + implemented.add(interfaze); + } + } + Class<?> superClass = clazz.getSuperclass(); + // Object has no superclass so check for null + if (superClass != null && !superClass.equals(Object.class)) { + getAllInterfaces(superClass, implemented); + } + } + +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java new file mode 100644 index 0000000000..8034de67fe --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java @@ -0,0 +1,99 @@ +/* + * 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.tuscany.sca.core; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.List; +import java.util.Set; +import java.util.logging.Level; +import java.util.logging.Logger; + +import org.apache.tuscany.sca.extensibility.ServiceDeclaration; +import org.apache.tuscany.sca.extensibility.ServiceDiscovery; + +/** + * Default implementation of an extension point to hold Tuscany module activators. + * + * @version $Rev$ $Date$ + */ +public class DefaultModuleActivatorExtensionPoint implements ModuleActivatorExtensionPoint { + private final static Logger logger = Logger.getLogger(DefaultModuleActivatorExtensionPoint.class.getName()); + + private List<ModuleActivator> activators = new ArrayList<ModuleActivator>(); + private boolean loadedActivators; + + /** + * Constructs a new extension point. + */ + public DefaultModuleActivatorExtensionPoint() { + } + + public void addModuleActivator(ModuleActivator activator) { + activators.add(activator); + } + + public List<ModuleActivator> getModuleActivators() { + loadModuleActivators(); + return activators; + } + + public void removeModuleActivator(Object activator) { + activators.remove(activator); + } + + /** + * Dynamically load module activators declared under META-INF/services + */ + private synchronized void loadModuleActivators() { + if (loadedActivators) + return; + + // Get the activator service declarations + Set<ServiceDeclaration> activatorDeclarations; + try { + activatorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(ModuleActivator.class); + } catch (IOException e) { + throw new IllegalStateException(e); + } + + // Load and instantiate module activators + for (ServiceDeclaration activatorDeclaration: activatorDeclarations) { + if (logger.isLoggable(Level.FINE)) { + logger.fine("Loading " + activatorDeclaration.getClassName()); + } + ModuleActivator activator = null; + try { + Class<ModuleActivator> activatorClass = (Class<ModuleActivator>)activatorDeclaration.loadClass(); + activator = activatorClass.newInstance(); + } catch (ClassNotFoundException e) { + throw new IllegalArgumentException(e); + } catch (InstantiationException e) { + throw new IllegalArgumentException(e); + } catch (IllegalAccessException e) { + throw new IllegalArgumentException(e); + } + addModuleActivator(activator); + } + + loadedActivators = true; + } + +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java new file mode 100644 index 0000000000..6f7c83c8d9 --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java @@ -0,0 +1,184 @@ +/* + * 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.tuscany.sca.core; + +import java.io.IOException; +import java.lang.reflect.Constructor; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Modifier; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Map; +import java.util.Set; + +import org.apache.tuscany.sca.extensibility.ServiceDiscovery; + +/** + * Default implementation of an extension point to hold Tuscany utility utilities. + * + * @version $Rev$ $Date$ + */ +public class DefaultUtilityExtensionPoint implements UtilityExtensionPoint { + private Map<Class<?>, Object> utilities = new HashMap<Class<?>, Object>(); + + private ExtensionPointRegistry extensionPoints; + + /** + * Constructs a new extension point. + */ + public DefaultUtilityExtensionPoint(ExtensionPointRegistry extensionPoints) { + this.extensionPoints = extensionPoints; + } + + /** + * Add a utility to the extension point. This default implementation + * stores utilities against the interfaces that they implement. + * + * @param utility The instance of the utility + * + * @throws IllegalArgumentException if utility is null + */ + public void addUtility(Object utility) { + if (utility == null) { + throw new IllegalArgumentException("Cannot register null as a Service"); + } + + Set<Class<?>> interfaces = getAllInterfaces(utility.getClass()); + for (Class<?> i : interfaces) { + utilities.put(i, utility); + } + } + + private Constructor<?> getConstructor(Constructor<?>[] constructors, Class<?>[] paramTypes) { + for (Constructor<?> c : constructors) { + Class<?>[] types = c.getParameterTypes(); + if (c.getParameterTypes().length == paramTypes.length) { + boolean found = true; + for (int i = 0; i < types.length; i++) { + if (types[i] != paramTypes[i]) { + found = false; + break; + } + } + if (found) { + return c; + } + } + } + return null; + } + + /** + * Get the utility by the interface that it implements + * + * @param utilityType The lookup key (utility interface) + * @return The instance of the utility + * + * @throws IllegalArgumentException if utilityType is null + */ + public <T> T getUtility(Class<T> utilityType) { + if (utilityType == null) { + throw new IllegalArgumentException("Cannot lookup Service of type null"); + } + + Object utility = utilities.get(utilityType); + if (utility == null) { + + // Dynamically load a utility class declared under META-INF/utilities + try { + Class<?> utilityClass = + ServiceDiscovery.getInstance().loadFirstServiceClass(utilityType); + if (utilityClass != null) { + // Construct the utility + Constructor<?>[] constructors = utilityClass.getConstructors(); + Constructor<?> constructor = getConstructor(constructors, new Class<?>[] {ExtensionPointRegistry.class}); + if (constructor != null) { + utility = constructor.newInstance(extensionPoints); + } else { + constructor = getConstructor(constructors, new Class<?>[] {}); + if (constructor != null) { + utility = constructor.newInstance(); + } else { + throw new IllegalArgumentException( + "No valid constructor is found for " + utilityClass); + } + } + + // Cache the loaded utility + addUtility(utility); + } + } catch (InvocationTargetException e) { + throw new IllegalArgumentException(e); + } catch (IOException e) { + throw new IllegalArgumentException(e); + } catch (ClassNotFoundException e) { + throw new IllegalArgumentException(e); + } catch (InstantiationException e) { + throw new IllegalArgumentException(e); + } catch (IllegalAccessException e) { + throw new IllegalArgumentException(e); + } + } + return utilityType.cast(utility); + } + + /** + * Remove a utility based on the interface that it implements + * + * @param utility The utility to remove + * + * @throws IllegalArgumentException if utility is null + */ + public void removeUtility(Object utility) { + if (utility == null) { + throw new IllegalArgumentException("Cannot remove null as a Service"); + } + + Set<Class<?>> interfaces = getAllInterfaces(utility.getClass()); + for (Class<?> i : interfaces) { + utilities.remove(i); + } + } + + /** + * Returns the set of interfaces implemented by the given class and its + * ancestors or a blank set if none + */ + private static Set<Class<?>> getAllInterfaces(Class<?> clazz) { + Set<Class<?>> implemented = new HashSet<Class<?>>(); + getAllInterfaces(clazz, implemented); + return implemented; + } + + private static void getAllInterfaces(Class<?> clazz, Set<Class<?>> implemented) { + Class<?>[] interfaces = clazz.getInterfaces(); + for (Class<?> interfaze : interfaces) { + if (Modifier.isPublic(interfaze.getModifiers())) { + implemented.add(interfaze); + } + } + Class<?> superClass = clazz.getSuperclass(); + // Object has no superclass so check for null + if (superClass != null && !superClass.equals(Object.class)) { + getAllInterfaces(superClass, implemented); + } + } + +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java new file mode 100644 index 0000000000..f2f67b2d52 --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java @@ -0,0 +1,56 @@ +/* + * 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.tuscany.sca.core; + + +/** + * The registry for the Tuscany core extension points. As the point of contact + * for all extension artifacts this registry allows loaded extensions to find + * all other parts of the system and register themselves appropriately. + * + * @version $Rev$ $Date$ + */ +public interface ExtensionPointRegistry { + + /** + * Add an extension point to the registry + * @param extensionPoint The instance of the extension point + * + * @throws IllegalArgumentException if extensionPoint is null + */ + void addExtensionPoint(Object extensionPoint); + + /** + * Get the extension point by the interface + * @param extensionPointType The lookup key (extension point interface) + * @return The instance of the extension point + * + * @throws IllegalArgumentException if extensionPointType is null + */ + <T> T getExtensionPoint(Class<T> extensionPointType); + + /** + * Remove an extension point + * @param extensionPoint The extension point to remove + * + * @throws IllegalArgumentException if extensionPoint is null + */ + void removeExtensionPoint(Object extensionPoint); +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java new file mode 100644 index 0000000000..dbfd0dcd90 --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java @@ -0,0 +1,60 @@ +/* + * 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.tuscany.sca.core; + + +/** + * ModuleActivator represents a module that plugs into the Tuscany system. Each + * module should provide an implementation of this interface and register the + * ModuleActivator implementation class by defining a file named + * + * "META-INF/services/org.apache.tuscany.core.ModuleActivator" + * + * The content of the file is the class name of the ModuleActivator implementation. + * The implementation class must have a no-arg constructor. The same instance + * will be used to invoke all the methods during different phases of the module + * activation. Note that the start and stop methods defined by this interface + * take a reference to the Tuscany SCA runtime ExtensionPointRegistry. This + * gives the ModuleActivator the opportunity to add extension points to the + * registry as it is requested to start up and remove them when it is requested + * to shut down. + * + * @version $Rev$ $Date$ + */ +public interface ModuleActivator { + + /** + * This method is invoked when the module is started by the Tuscany system. + * It can be used by this module to register extensions against extension + * points. + * + * @param registry The extension point registry + */ + void start(ExtensionPointRegistry registry); + + /** + * This method is invoked when the module is stopped by the Tuscany system. + * It can be used by this module to unregister extensions against the + * extension points. + * + * @param registry The extension point registry + */ + void stop(ExtensionPointRegistry registry); +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java new file mode 100644 index 0000000000..ec0f12b8ba --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java @@ -0,0 +1,53 @@ +/* + * 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.tuscany.sca.core; + +import java.util.List; + + +/** + * The extension point for the Tuscany module activator extensions. + * + * @version $Rev$ $Date$ + */ +public interface ModuleActivatorExtensionPoint { + + /** + * Add a module activator extension to the extension point + * @param activator The instance of the module activator + * + * @throws IllegalArgumentException if activator is null + */ + void addModuleActivator(ModuleActivator activator); + + /** + * Returns the module activator extensions. + * @return The module activator extensions + */ + List<ModuleActivator> getModuleActivators(); + + /** + * Remove a module activator + * @param activator The module activator to remove + * + * @throws IllegalArgumentException if activator is null + */ + void removeModuleActivator(Object activator); +} diff --git a/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java new file mode 100644 index 0000000000..6b14b95666 --- /dev/null +++ b/sca-java-1.x/tags/1.6.1-TUSCANY-3909/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java @@ -0,0 +1,54 @@ +/* + * 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.tuscany.sca.core; + + +/** + * The extension point for the Tuscany core utility extensions. + * + * @version $Rev$ $Date$ + */ +public interface UtilityExtensionPoint { + + /** + * Add a utility to the extension point + * @param utility The instance of the utility + * + * @throws IllegalArgumentException if utility is null + */ + void addUtility(Object utility); + + /** + * Get the utility by the interface + * @param utilityType The lookup key (utility interface) + * @return The instance of the utility + * + * @throws IllegalArgumentException if utilityType is null + */ + <T> T getUtility(Class<T> utilityType); + + /** + * Remove a utility + * @param utility The utility to remove + * + * @throws IllegalArgumentException if utility is null + */ + void removeUtility(Object utility); +} |