source: branches/autoquest-core-tasktrees-alignment/src/main/java/de/ugoe/cs/autoquest/tasktrees/treeimpl/UserSession.java

//   Copyright 2012 Georg-August-Universität Göttingen, Germany
//
//   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 de.ugoe.cs.autoquest.tasktrees.treeimpl;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstance;
import de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession;

// TODO: Auto-generated Javadoc
/**
 * <p>
 * this is the default implementation of the interface {@link IUserSession}. It
 * does not do anything fancy except implementing the interface.
 * </p>
 * 
 * @author Patrick Harms
 */
class UserSession implements IUserSession {

        /** <p> default serial version UID </p>. */
        private static final long serialVersionUID = 1L;

        /** <p> the task instances belonging to the user session </p>. */
        private List<ITaskInstance> executedTasks = new ArrayList<ITaskInstance>();

        /**
         * <p>
         * used internally to add a task instance to the user session at a specific
         * position
         * </p>.
         *
         * @param index            the index the task instance shall be added to
         * @param taskInstance            the task instance to be added
         */
        void addExecutedTask(int index, ITaskInstance taskInstance) {
                executedTasks.add(index, taskInstance);
        }

        /**
         * <p>
         * used internally to add a task instance to the user session
         * </p>.
         *
         * @param taskInstance            the task instance to be added
         */
        void addExecutedTask(ITaskInstance taskInstance) {
                executedTasks.add(taskInstance);
        }

        /*
         * (non-Javadoc)
         * 
         * @see java.lang.Object#clone()
         */
        @Override
        public synchronized IUserSession clone() {
                UserSession clone = null;
                try {
                        clone = (UserSession) super.clone();

                        clone.executedTasks = new LinkedList<ITaskInstance>();

                        for (final ITaskInstance child : executedTasks) {
                                clone.executedTasks.add(child.clone());
                        }

                } catch (final CloneNotSupportedException e) {
                        // this should never happen. Therefore simply dump the exception
                        e.printStackTrace();
                }

                return clone;
        }

        /*
         * (non-Javadoc)
         * 
         * @see
         * de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession#equals(IUserSession)
         */
        @Override
        public boolean equals(IUserSession userSession) {
                // task instances are only equal if they are identical or if they have
                // the same id
                // (may happen, if they are cloned)
                return (this == userSession)
                                || (this.hashCode() == userSession.hashCode());
        }

        /*
         * (non-Javadoc)
         * 
         * @see de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstanceList#get(int)
         */
        @Override
        public ITaskInstance get(int index) {
                return executedTasks.get(index);
        }

        /*
         * (non-Javadoc)
         * 
         * @see
         * de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession#getExecutedTasks()
         */
        @Override
        public List<ITaskInstance> getExecutedTasks() {
                return Collections.unmodifiableList(executedTasks);
        }

        /*
         * (non-Javadoc)
         * 
         * @see java.lang.Object#hashCode()
         */
        @Override
        public synchronized int hashCode() {
                return super.hashCode();
        }

        /*
         * (non-Javadoc)
         * 
         * @see java.lang.Iterable#iterator()
         */
        @Override
        public Iterator<ITaskInstance> iterator() {
                return executedTasks.iterator();
        }

        /**
         * <p>
         * used internally to remove a task instance from the user session
         * </p>.
         *
         * @param index            the index of the task instance to be removed
         */
        void removeExecutedTask(int index) {
                executedTasks.remove(index);
        }

        /*
         * (non-Javadoc)
         * 
         * @see de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstanceList#size()
         */
        @Override
        public int size() {
                return executedTasks.size();
        }

        /*
         * (non-Javadoc)
         * 
         * @see java.lang.Object#toString()
         */
        @Override
        public synchronized String toString() {
                return "session (" + executedTasks.size() + " task instances)";
        }

}