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/* * Copyright 2012-2014 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.lightadmin.core.util; import org.lightadmin.api.config.AdministrationConfiguration; import org.lightadmin.api.config.annotation.Administration; import org.lightadmin.core.config.domain.unit.ConfigurationUnit; import org.lightadmin.core.config.domain.unit.ConfigurationUnitBuilder; import org.lightadmin.core.config.domain.unit.DomainConfigurationUnitType; import org.springframework.util.ClassUtils; import java.lang.reflect.Constructor; import java.lang.reflect.Method; import java.lang.reflect.ParameterizedType; import static org.springframework.beans.BeanUtils.instantiateClass; import static org.springframework.core.annotation.AnnotationUtils.findAnnotation; import static org.springframework.util.ClassUtils.getConstructorIfAvailable; import static org.springframework.util.ClassUtils.getMethodIfAvailable; import static org.springframework.util.ReflectionUtils.invokeMethod; public abstract class DomainConfigurationUtils { public static Class<?> configurationDomainType(Class clazz) { if (isAnnotationBasedConfigurationCandidate(clazz)) { final Administration annotation = findAnnotation(clazz, Administration.class); return annotation == null ? null : annotation.value(); } if (isSuperClassBasedConfigurationCandidate(clazz)) { final ParameterizedType genericSuperclass = (ParameterizedType) clazz.getGenericSuperclass(); return (Class<?>) genericSuperclass.getActualTypeArguments()[0]; } throw new RuntimeException("Unknown configuration candidate"); } public static boolean isAnnotationBasedConfigurationCandidate(Class clazz) { return hasAdministrationAnnotation(clazz); } public static boolean isSuperClassBasedConfigurationCandidate(Class clazz) { return ClassUtils.isAssignable(AdministrationConfiguration.class, clazz); } private static boolean hasAdministrationAnnotation(Class clazz) { return findAnnotation(clazz, Administration.class) != null; } @SuppressWarnings({ "unchecked" }) public static <T extends ConfigurationUnit> T initializeConfigurationUnitWithBuilder( final AdministrationConfiguration configurationInstance, DomainConfigurationUnitType configurationUnitType, Class<? extends ConfigurationUnitBuilder<T>> builderInterface, Class<? extends ConfigurationUnitBuilder<T>> concreteBuilderClass) { final Class<? extends AdministrationConfiguration> configurationClass = configurationInstance.getClass(); final Class<?> domainType = configurationDomainType(configurationClass); final Method method = getMethodIfAvailable(configurationClass, configurationUnitType.getName(), builderInterface); final ConfigurationUnitBuilder<T> builder = instantiateBuilder(concreteBuilderClass, domainType, configurationUnitType); try { return (T) invokeMethod(method, configurationInstance, builder); } catch (Exception ex) { return instantiateBuilder(concreteBuilderClass, domainType, configurationUnitType).build(); } } @SuppressWarnings({ "unchecked" }) public static <T extends ConfigurationUnit> T initializeConfigurationUnitWithBuilder( final Class<?> configurationClass, DomainConfigurationUnitType configurationUnitType, Class<? extends ConfigurationUnitBuilder<T>> builderInterface, Class<? extends ConfigurationUnitBuilder<T>> concreteBuilderClass) { final Class<?> domainType = configurationDomainType(configurationClass); final Method method = getMethodIfAvailable(configurationClass, configurationUnitType.getName(), builderInterface); final ConfigurationUnitBuilder<T> builder = instantiateBuilder(concreteBuilderClass, domainType, configurationUnitType); if (method != null) { try { return (T) invokeMethod(method, null, builder); } catch (Exception ex) { return instantiateBuilder(concreteBuilderClass, domainType, configurationUnitType).build(); } } return builder.build(); } private static <T extends ConfigurationUnit> ConfigurationUnitBuilder<T> instantiateBuilder( final Class<? extends ConfigurationUnitBuilder<T>> concreteBuilderClass, final Class domainType, DomainConfigurationUnitType configurationUnitType) { Constructor<? extends ConfigurationUnitBuilder<T>> extendedConstructor = getConstructorIfAvailable( concreteBuilderClass, Class.class, DomainConfigurationUnitType.class); if (extendedConstructor != null) { return instantiateClass(extendedConstructor, domainType, configurationUnitType); } Constructor<? extends ConfigurationUnitBuilder<T>> constructor = getConstructorIfAvailable( concreteBuilderClass, Class.class); if (constructor != null) { return instantiateClass(constructor, domainType); } return instantiateClass(concreteBuilderClass); } }