# ConcurrentEntityStateModificationException.java

    /*  Copyright 2007 Niclas Hedhman.
     *
     * 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.spi.entitystore;

    import java.util.Collection;
    import org.qi4j.api.entity.EntityReference;

    /**
     * This exception should be thrown if the EntityStore detects that the entities being saved have been changed
     * since they were created.
     */
    public class ConcurrentEntityStateModificationException
        extends EntityStoreException
    {
        private Collection<EntityReference> modifiedEntities;

        public ConcurrentEntityStateModificationException( Collection<EntityReference> modifiedEntities )
        {
            super("Entities changed concurrently:" + modifiedEntities);
            this.modifiedEntities = modifiedEntities;
        }

        public Collection<EntityReference> modifiedEntities()
        {
            return modifiedEntities;
        }
    }