# SideEffectsModel.java

    /*
     * Copyright (c) 2008, Rickard Öberg. All Rights Reserved.
     *
     * 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.qi4j.runtime.composite;

    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.util.ArrayList;
    import java.util.Collections;
    import java.util.List;
    import org.qi4j.api.sideeffect.SideEffectsDescriptor;
    import org.qi4j.functional.HierarchicalVisitor;
    import org.qi4j.functional.Iterables;
    import org.qi4j.functional.VisitableHierarchy;
    import org.qi4j.runtime.injection.Dependencies;
    import org.qi4j.runtime.injection.DependencyModel;
    import org.qi4j.spi.module.ModuleSpi;

    /**
     * JAVADOC
     */
    public final class SideEffectsModel
        implements SideEffectsDescriptor, Dependencies, VisitableHierarchy<Object, Object>
    {
        public static final SideEffectsModel EMPTY_SIDEEFFECTS = new SideEffectsModel( Collections.<SideEffectModel>emptyList() );

        private List<SideEffectModel> sideEffectModels = null;

        public SideEffectsModel( List<SideEffectModel> sideEffectModels )
        {
            this.sideEffectModels = sideEffectModels;
        }

        @Override
        public Iterable<DependencyModel> dependencies()
        {
            return Iterables.flattenIterables( Iterables.map( Dependencies.DEPENDENCIES_FUNCTION, sideEffectModels ) );
        }

        // Context
        public SideEffectsInstance newInstance( Method method, ModuleSpi moduleInstance, InvocationHandler invoker )
        {
            ProxyReferenceInvocationHandler proxyHandler = new ProxyReferenceInvocationHandler();
            SideEffectInvocationHandlerResult result = new SideEffectInvocationHandlerResult();
            List<InvocationHandler> sideEffects = new ArrayList<InvocationHandler>( sideEffectModels.size() );
            for( SideEffectModel sideEffectModel : sideEffectModels )
            {
                InvocationHandler sideEffect = sideEffectModel.newInstance( moduleInstance, result, proxyHandler, method );
                sideEffects.add( sideEffect );
            }
            return new SideEffectsInstance( sideEffects, result, proxyHandler, invoker );
        }

        @Override
        public <ThrowableType extends Throwable> boolean accept( HierarchicalVisitor<? super Object, ? super Object, ThrowableType> modelVisitor )
            throws ThrowableType
        {
            if( modelVisitor.visitEnter( this ) )
            {
                for( SideEffectModel sideEffectModel : sideEffectModels )
                {
                    if( !sideEffectModel.accept( modelVisitor ) )
                    {
                        break;
                    }
                }
            }
            return modelVisitor.visitLeave( this );
        }
    }