vaadin-framework/src/com/itmill/toolkit/data/util/IndexedContainer.java

/* 
@ITMillApache2LicenseForJavaFiles@
 */

package com.itmill.toolkit.data.util;

import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.EventObject;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.NoSuchElementException;

import com.itmill.toolkit.data.Container;
import com.itmill.toolkit.data.Item;
import com.itmill.toolkit.data.Property;

/**
 * Indexed container implementation.
 * <p>
 * A list implementation of the <code>com.itmill.toolkit.data.Container</code>
 * interface. A list is a ordered collection wherein the user has a precise
 * control over where in the list each new Item is inserted. The user may access
 * the Items by their integer index (position in the list) or by their Item ID.
 * </p>
 * 
 * @see com.itmill.toolkit.data.Container
 * 
 * @author IT Mill Ltd.
 * @version
 * @VERSION@
 * @since 3.0
 */

public class IndexedContainer implements Container, Container.Indexed,
        Container.ItemSetChangeNotifier, Container.PropertySetChangeNotifier,
        Property.ValueChangeNotifier, Container.Sortable, Comparator,
        Cloneable, Container.Filterable {

    /* Internal structure *************************************************** */

    /**
     * Linked list of ordered Item IDs.
     */
    private ArrayList itemIds = new ArrayList();

    /** List of item ids that passes the filtering */
    private LinkedHashSet filteredItemIds = null;

    /**
     * Linked list of ordered Property IDs.
     */
    private ArrayList propertyIds = new ArrayList();

    /**
     * Property ID to type mapping.
     */
    private Hashtable types = new Hashtable();

    /**
     * Hash of Items, where each Item is implemented as a mapping from Property
     * ID to Property value.
     */
    private Hashtable items = new Hashtable();

    /**
     * Set of properties that are read-only.
     */
    private HashSet readOnlyProperties = new HashSet();

    /**
     * List of all Property value change event listeners listening all the
     * properties.
     */
    private LinkedList propertyValueChangeListeners = null;

    /**
     * Data structure containing all listeners interested in changes to single
     * Properties. The data structure is a hashtable mapping Property IDs to a
     * hashtable that maps Item IDs to a linked list of listeners listening
     * Property identified by given Property ID and Item ID.
     */
    private Hashtable singlePropertyValueChangeListeners = null;

    /**
     * List of all Property set change event listeners.
     */
    private LinkedList propertySetChangeListeners = null;

    /**
     * List of all container Item set change event listeners.
     */
    private LinkedList itemSetChangeListeners = null;

    /**
     * Temporary store for sorting property ids.
     */
    private Object[] sortPropertyId;

    /**
     * Temporary store for sorting direction.
     */
    private boolean[] sortDirection;

    /**
     * Filters that are applied to the container to limit the items visible in
     * it
     */
    private HashSet filters;

    /* Container constructors *********************************************** */

    public IndexedContainer() {
    }

    public IndexedContainer(Collection itemIds) {
        if (items != null) {
            for (final Iterator i = itemIds.iterator(); i.hasNext();) {
                this.addItem(i.next());
            }
        }
    }

    /* Container methods **************************************************** */

    /**
     * Gets the Item with the given Item ID from the list. If the list does not
     * contain the requested Item (or it is filtered to be invisible),
     * <code>null</code> is returned.
     * 
     * @param itemId
     *                the ID of the Item to retrieve.
     * @return the Item with the given ID or <code>null</code> if the Item is
     *         not found in the list
     */
    public Item getItem(Object itemId) {
        if (items.containsKey(itemId)
                && (filteredItemIds == null || filteredItemIds.contains(itemId))) {
            return new IndexedContainerItem(itemId);
        }
        return null;
    }

    /**
     * Gets the ID's of all Items stored in the list. The ID's are returned as a
     * unmodifiable collection.
     * 
     * @return unmodifiable collection of Item IDs
     */
    public Collection getItemIds() {
        if (filteredItemIds != null) {
            return Collections.unmodifiableCollection(filteredItemIds);
        }
        return Collections.unmodifiableCollection(itemIds);
    }

    /**
     * Gets the ID's of all Properties stored in the list. The ID's are returned
     * as a unmodifiable collection.
     * 
     * @return unmodifiable collection of Property IDs
     */
    public Collection getContainerPropertyIds() {
        return Collections.unmodifiableCollection(propertyIds);
    }

    /**
     * Gets the type of a Property stored in the list.
     * 
     * @param id
     *                the ID of the Property.
     * @return Type of the requested Property
     */
    public Class getType(Object propertyId) {
        return (Class) types.get(propertyId);
    }

    /**
     * Gets the Property identified by the given Item ID and Property ID from
     * the lsit. If the list does not contain the Property, <code>null</code>
     * is returned.
     * 
     * @param itemId
     *                the ID of the Item which contains the requested Property.
     * @param propertyId
     *                the ID of the Property to retrieve.
     * @return Property with the given ID or <code>null</code>
     * 
     * @see com.itmill.toolkit.data.Container#getContainerProperty(Object,
     *      Object)
     */
    public Property getContainerProperty(Object itemId, Object propertyId) {
        if (filteredItemIds == null) {
            if (!items.containsKey(itemId)) {
                return null;
            }
        } else if (!filteredItemIds.contains(itemId)) {
            return null;
        }

        return new IndexedContainerProperty(itemId, propertyId);
    }

    /**
     * Gets the number of Items in the list.
     * 
     * @return number of Items in the list
     */
    public int size() {
        if (filteredItemIds == null) {
            return itemIds.size();
        }
        return filteredItemIds.size();
    }

    /**
     * Tests if the list contains the specified Item
     * 
     * @param itemId
     *                the ID the of Item to be tested for.
     * @return <code>true</code> if the operation succeeded,
     *         <code>false</code> if not
     */
    public boolean containsId(Object itemId) {
        if (filteredItemIds != null) {
            return filteredItemIds.contains(itemId);
        }
        return items.containsKey(itemId);
    }

    /**
     * Adds a new Property to all Items in the list. The Property ID, data type
     * and default value of the new Property are given as parameters.
     * 
     * @param propertyId
     *                the ID of the new Property.
     * @param type
     *                the Data type of the new Property.
     * @param defaultValue
     *                the value all created Properties are initialized to.
     * @return <code>true</code> if the operation succeeded,
     *         <code>false</code> if not
     */
    public boolean addContainerProperty(Object propertyId, Class type,
            Object defaultValue) {

        // Fails, if nulls are given
        if (propertyId == null || type == null) {
            return false;
        }

        // Fails if the Property is already present
        if (propertyIds.contains(propertyId)) {
            return false;
        }

        // Adds the Property to Property list and types
        propertyIds.add(propertyId);
        types.put(propertyId, type);

        // If default value is given, set it
        if (defaultValue != null) {
            for (final Iterator i = itemIds.iterator(); i.hasNext();) {
                getItem(i.next()).getItemProperty(propertyId).setValue(
                        defaultValue);
            }
        }

        // Sends a change event
        fireContainerPropertySetChange();

        return true;
    }

    /**
     * Removes all Items from the list.
     * <p>
     * Note : The Property ID and type information is preserved.
     * </p>
     * 
     * @return <code>true</code> if the operation succeeded,
     *         <code>false</code> if not
     */
    public boolean removeAllItems() {

        // Removes all Items
        itemIds.clear();
        items.clear();
        if (filteredItemIds != null) {
            filteredItemIds.clear();
        }

        // Sends a change event
        fireContentsChange();

        return true;
    }

    /**
     * Creates a new Item into the list, and assign it an automatic ID. The new
     * ID is returned, or <code>null</code> if the operation fails. After a
     * successful call you can use the
     * {@link #getItem(Object ItemId) <code>getItem</code>}method to fetch the
     * Item.
     * 
     * @return ID of the newly created Item, or <code>null</code> in case of a
     *         failure
     */
    public Object addItem() {

        // Creates a new id
        final Object id = new Object();

        // Adds the Item into container
        addItem(id);

        return id;
    }

    /**
     * Creates a new Item with the given ID into the list. The new Item is
     * returned, and it is ready to have its Properties modified. Returns
     * <code>null</code> if the operation fails or the Container already
     * contains a Item with the given ID.
     * 
     * @param itemId
     *                the ID of the Item to be created.
     * @return Created new Item, or <code>null</code> in case of a failure
     */
    public Item addItem(Object itemId) {

        // Makes sure that the Item has not been created yet
        if (items.containsKey(itemId)) {
            return null;
        }

        // Adds the Item to container
        itemIds.add(itemId);
        items.put(itemId, new Hashtable());
        final Item item = getItem(itemId);
        if (filteredItemIds != null) {
            if (passesFilters(item)) {
                filteredItemIds.add(itemId);
            }
        }

        // Sends the event
        fireContentsChange();

        return item;
    }

    /**
     * Removes the Item corresponding to the given Item ID from the list.
     * 
     * @param itemId
     *                the ID of the Item to remove.
     * @return <code>true</code> if the operation succeeded,
     *         <code>false</code> if not
     */
    public boolean removeItem(Object itemId) {

        if (items.remove(itemId) == null) {
            return false;
        }
        itemIds.remove(itemId);
        if (filteredItemIds != null) {
            filteredItemIds.remove(itemId);
        }

        fireContentsChange();

        return true;
    }

    /**
     * Removes a Property specified by the given Property ID from the list. Note
     * that the Property will be removed from all Items in the list.
     * 
     * @param propertyId
     *                the ID of the Property to remove.
     * @return <code>true</code> if the operation succeeded,
     *         <code>false</code> if not
     */
    public boolean removeContainerProperty(Object propertyId) {

        // Fails if the Property is not present
        if (!propertyIds.contains(propertyId)) {
            return false;
        }

        // Removes the Property to Property list and types
        propertyIds.remove(propertyId);
        types.remove(propertyId);

        // If remove the Property from all Items
        for (final Iterator i = itemIds.iterator(); i.hasNext();) {
            ((Hashtable) items.get(i.next())).remove(propertyId);
        }

        // Sends a change event
        fireContainerPropertySetChange();

        return true;
    }

    /* Container.Ordered methods ******************************************** */

    /**
     * Gets the ID of the first Item in the list.
     * 
     * @return ID of the first Item in the list
     */
    public Object firstItemId() {
        try {
            if (filteredItemIds != null) {
                return filteredItemIds.iterator().next();
            }
            return itemIds.get(0);
        } catch (final IndexOutOfBoundsException e) {
        } catch (final NoSuchElementException e) {
        }
        return null;
    }

    /**
     * Gets the ID of the last Item in the list.
     * 
     * @return ID of the last Item in the list
     */
    public Object lastItemId() {
        try {
            if (filteredItemIds != null) {
                final Iterator i = filteredItemIds.iterator();
                Object last = null;
                while (i.hasNext()) {
                    last = i.next();
                }
                return last;
            }
            return itemIds.get(itemIds.size() - 1);
        } catch (final IndexOutOfBoundsException e) {
        }
        return null;
    }

    /**
     * Gets the ID of the Item following the Item that corresponds to the
     * itemId. If the given Item is the last or not found in the list,
     * <code>null</code> is returned.
     * 
     * @param itemId
     *                the ID of an Item in the list.
     * @return ID of the next Item or <code>null</code>
     */
    public Object nextItemId(Object itemId) {
        if (filteredItemIds != null) {
            if (!filteredItemIds.contains(itemId)) {
                return null;
            }
            final Iterator i = filteredItemIds.iterator();
            if (itemId == null) {
                return null;
            }
            while (i.hasNext() && !itemId.equals(i.next())) {
                ;
            }
            if (i.hasNext()) {
                return i.next();
            }
            return null;
        }
        try {
            return itemIds.get(itemIds.indexOf(itemId) + 1);
        } catch (final IndexOutOfBoundsException e) {
            return null;
        }
    }

    /**
     * Gets the ID of the Item preceding the Item that corresponds to the
     * itemId. If the given Item is the first or not found in the list,
     * <code>null</code> is returned.
     * 
     * @param itemId
     *                the ID of an Item in the list.
     * @return ID of the previous Item or <code>null</code>
     */
    public Object prevItemId(Object itemId) {
        if (filteredItemIds != null) {
            if (!filteredItemIds.contains(itemId)) {
                return null;
            }
            final Iterator i = filteredItemIds.iterator();
            if (itemId == null) {
                return null;
            }
            Object prev = null;
            Object current;
            while (i.hasNext() && !itemId.equals(current = i.next())) {
                prev = current;
            }
            return prev;
        }
        try {
            return itemIds.get(itemIds.indexOf(itemId) - 1);
        } catch (final IndexOutOfBoundsException e) {
            return null;
        }
    }

    /**
     * Tests if the Item corresponding to the given Item ID is the first Item in
     * the list.
     * 
     * @param itemId
     *                the ID of an Item in the list.
     * @return <code>true</code> if the Item is first in the list,
     *         <code>false</code> if not
     */
    public boolean isFirstId(Object itemId) {
        if (filteredItemIds != null) {
            try {
                final Object first = filteredItemIds.iterator().next();
                return (itemId != null && itemId.equals(first));
            } catch (final NoSuchElementException e) {
                return false;
            }
        }
        return (size() >= 1 && itemIds.get(0).equals(itemId));
    }

    /**
     * Tests if the Item corresponding to the given Item ID is the last Item in
     * the list.
     * 
     * @param itemId
     *                the ID of an Item in the list.
     * @return <code>true</code> if the Item is last in the list,
     *         <code>false</code> if not
     */
    public boolean isLastId(Object itemId) {
        if (filteredItemIds != null) {
            try {
                Object last = null;
                for (final Iterator i = filteredItemIds.iterator(); i.hasNext();) {
                    last = i.next();
                }
                return (itemId != null && itemId.equals(last));
            } catch (final NoSuchElementException e) {
                return false;
            }
        }
        final int s = size();
        return (s >= 1 && itemIds.get(s - 1).equals(itemId));
    }

    /**
     * @see com.itmill.toolkit.data.Container.Ordered#addItemAfter(Object,
     *      Object)
     */
    public Item addItemAfter(Object previousItemId, Object newItemId) {

        // Get the index of the addition
        int index = 0;
        if (previousItemId != null) {
            index = 1 + indexOfId(previousItemId);
            if (index <= 0 || index > size()) {
                return null;
            }
        }

        return addItemAt(index, newItemId);
    }

    /**
     * @see com.itmill.toolkit.data.Container.Ordered#addItemAfter(Object)
     */
    public Object addItemAfter(Object previousItemId) {

        // Get the index of the addition
        int index = 0;
        if (previousItemId != null) {
            index = 1 + indexOfId(previousItemId);
            if (index <= 0 || index > size()) {
                return null;
            }
        }

        return addItemAt(index);
    }

    /**
     * Gets ID with the index. The following is true for the index: 0 <= index <
     * size().
     * 
     * @return ID in the given index.
     * @param index
     *                Index of the requested ID in the container.
     */
    public Object getIdByIndex(int index) {

        if (filteredItemIds != null) {
            if (index < 0) {
                throw new IndexOutOfBoundsException();
            }
            try {
                final Iterator i = filteredItemIds.iterator();
                while (index-- > 0) {
                    i.next();
                }
                return i.next();
            } catch (final NoSuchElementException e) {
                throw new IndexOutOfBoundsException();
            }
        }

        return itemIds.get(index);
    }

    /**
     * Gets the index of an id. The following is true for the index: 0 <= index <
     * size().
     * 
     * @return Index of the Item or -1 if the Item is not in the container.
     * @param itemId
     *                ID of an Item in the collection
     */
    public int indexOfId(Object itemId) {
        if (filteredItemIds != null) {
            int index = 0;
            if (itemId == null) {
                return -1;
            }
            try {
                for (final Iterator i = filteredItemIds.iterator(); itemId
                        .equals(i.next());) {
                    index++;
                }
                return index;
            } catch (final NoSuchElementException e) {
                return -1;
            }
        }
        return itemIds.indexOf(itemId);
    }

    /**
     * @see com.itmill.toolkit.data.Container.Indexed#addItemAt(int, Object)
     */
    public Item addItemAt(int index, Object newItemId) {

        // Make sure that the Item has not been created yet
        if (items.containsKey(newItemId)) {
            return null;
        }

        // Adds the Item to container
        itemIds.add(index, newItemId);
        items.put(newItemId, new Hashtable());

        if (filteredItemIds != null) {
            updateContainerFiltering();
        } else {
            fireContentsChange();
        }

        return getItem(newItemId);
    }

    /**
     * @see com.itmill.toolkit.data.Container.Indexed#addItemAt(int)
     */
    public Object addItemAt(int index) {

        // Creates a new id
        final Object id = new Object();

        // Adds the Item into container
        addItemAt(index, id);

        return id;
    }

    /* Event notifiers ****************************************************** */

    /**
     * An <code>event</code> object specifying the list whose Property set has
     * changed.
     * 
     * @author IT Mill Ltd.
     * @version
     * @VERSION@
     * @since 3.0
     */
    private class PropertySetChangeEvent extends EventObject implements
            Container.PropertySetChangeEvent {

        /**
         * Serial generated by eclipse.
         */
        private static final long serialVersionUID = 3257002172528079926L;

        private PropertySetChangeEvent(IndexedContainer source) {
            super(source);
        }

        /**
         * Gets the list whose Property set has changed.
         * 
         * @return source object of the event as a Container
         */
        public Container getContainer() {
            return (Container) getSource();
        }
    }

    /**
     * An <code>event</code> object specifying the list whose Item set has
     * changed.
     * 
     * @author IT Mill Ltd.
     * @version
     * @VERSION@
     * @since 3.0
     */
    private class ItemSetChangeEvent extends EventObject implements
            Container.ItemSetChangeEvent {

        /**
         * Serial generated by eclipse.
         */
        private static final long serialVersionUID = 3832616279386372147L;

        private ItemSetChangeEvent(IndexedContainer source) {
            super(source);
        }

        /**
         * Gets the list whose Item set has changed.
         * 
         * @return source object of the event as a Container
         */
        public Container getContainer() {
            return (Container) getSource();
        }

    }

    /**
     * An <code>event</code> object specifying the Propery in a list whose
     * value has changed.
     * 
     * @author IT Mill Ltd.
     * @version
     * @VERSION@
     * @since 3.0
     */
    private class PropertyValueChangeEvent extends EventObject implements
            Property.ValueChangeEvent {

        /**
         * Serial generated by eclipse.
         */
        private static final long serialVersionUID = 3833749884498359857L;

        private PropertyValueChangeEvent(Property source) {
            super(source);
        }

        /**
         * Gets the Property whose value has changed.
         * 
         * @return source object of the event as a Property
         */
        public Property getProperty() {
            return (Property) getSource();
        }

    }

    /**
     * Registers a new Property set change listener for this list.
     * 
     * @param listener
     *                the new Listener to be registered.
     */
    public void addListener(Container.PropertySetChangeListener listener) {
        if (propertySetChangeListeners == null) {
            propertySetChangeListeners = new LinkedList();
        }
        propertySetChangeListeners.add(listener);
    }

    /**
     * Removes a previously registered Property set change listener.
     * 
     * @param listener
     *                the listener to be removed.
     */
    public void removeListener(Container.PropertySetChangeListener listener) {
        if (propertySetChangeListeners != null) {
            propertySetChangeListeners.remove(listener);
        }
    }

    /**
     * Adds a Item set change listener for the list.
     * 
     * @param listener
     *                the listener to be added.
     */
    public void addListener(Container.ItemSetChangeListener listener) {
        if (itemSetChangeListeners == null) {
            itemSetChangeListeners = new LinkedList();
        }
        itemSetChangeListeners.add(listener);
    }

    /**
     * Removes a Item set change listener from the object.
     * 
     * @param listener
     *                the listener to be removed.
     */
    public void removeListener(Container.ItemSetChangeListener listener) {
        if (itemSetChangeListeners != null) {
            itemSetChangeListeners.remove(listener);
        }
    }

    /**
     * Registers a new value change listener for this object.
     * 
     * @param listener
     *                the new Listener to be registered
     */
    public void addListener(Property.ValueChangeListener listener) {
        if (propertyValueChangeListeners == null) {
            propertyValueChangeListeners = new LinkedList();
        }
        propertyValueChangeListeners.add(listener);
    }

    /**
     * Removes a previously registered value change listener.
     * 
     * @param listener
     *                the listener to be removed.
     */
    public void removeListener(Property.ValueChangeListener listener) {
        if (propertyValueChangeListeners != null) {
            propertyValueChangeListeners.remove(listener);
        }
    }

    /**
     * Sends a Property value change event to all interested listeners.
     * 
     * @param source
     *                the IndexedContainerProperty object.
     */
    private void firePropertyValueChange(IndexedContainerProperty source) {

        // Sends event to listeners listening all value changes
        if (propertyValueChangeListeners != null) {
            final Object[] l = propertyValueChangeListeners.toArray();
            final Property.ValueChangeEvent event = new IndexedContainer.PropertyValueChangeEvent(
                    source);
            for (int i = 0; i < l.length; i++) {
                ((Property.ValueChangeListener) l[i]).valueChange(event);
            }
        }

        // Sends event to single property value change listeners
        if (singlePropertyValueChangeListeners != null) {
            final Hashtable propertySetToListenerListMap = (Hashtable) singlePropertyValueChangeListeners
                    .get(source.propertyId);
            if (propertySetToListenerListMap != null) {
                final LinkedList listenerList = (LinkedList) propertySetToListenerListMap
                        .get(source.itemId);
                if (listenerList != null) {
                    final Property.ValueChangeEvent event = new IndexedContainer.PropertyValueChangeEvent(
                            source);
                    for (final Iterator i = listenerList.iterator(); i
                            .hasNext();) {
                        ((Property.ValueChangeListener) i.next())
                                .valueChange(event);
                    }
                }
            }
        }

    }

    /**
     * Sends a Property set change event to all interested listeners.
     */
    private void fireContainerPropertySetChange() {
        if (propertySetChangeListeners != null) {
            final Object[] l = propertySetChangeListeners.toArray();
            final Container.PropertySetChangeEvent event = new IndexedContainer.PropertySetChangeEvent(
                    this);
            for (int i = 0; i < l.length; i++) {
                ((Container.PropertySetChangeListener) l[i])
                        .containerPropertySetChange(event);
            }
        }
    }

    /**
     * Sends Item set change event to all registered interested listeners.
     */
    private void fireContentsChange() {
        if (itemSetChangeListeners != null) {
            final Object[] l = itemSetChangeListeners.toArray();
            final Container.ItemSetChangeEvent event = new IndexedContainer.ItemSetChangeEvent(
                    this);
            for (int i = 0; i < l.length; i++) {
                ((Container.ItemSetChangeListener) l[i])
                        .containerItemSetChange(event);
            }
        }
    }

    /**
     * Adds new single Property change listener.
     * 
     * @param propertyId
     *                the ID of the Property to add.
     * @param itemId
     *                the ID of the Item .
     * @param listener
     *                the listener to be added.
     */
    private void addSinglePropertyChangeListener(Object propertyId,
            Object itemId, Property.ValueChangeListener listener) {
        if (listener != null) {
            if (singlePropertyValueChangeListeners == null) {
                singlePropertyValueChangeListeners = new Hashtable();
            }
            Hashtable propertySetToListenerListMap = (Hashtable) singlePropertyValueChangeListeners
                    .get(propertyId);
            if (propertySetToListenerListMap == null) {
                propertySetToListenerListMap = new Hashtable();
                singlePropertyValueChangeListeners.put(propertyId,
                        propertySetToListenerListMap);
            }
            LinkedList listenerList = (LinkedList) propertySetToListenerListMap
                    .get(itemId);
            if (listenerList == null) {
                listenerList = new LinkedList();
                propertySetToListenerListMap.put(itemId, listenerList);
            }
            listenerList.addLast(listener);
        }
    }

    /**
     * Removes a previously registered single Property change listener.
     * 
     * @param propertyId
     *                the ID of the Property to remove.
     * @param itemId
     *                the ID of the Item.
     * @param listener
     *                the listener to be removed.
     */
    private void removeSinglePropertyChangeListener(Object propertyId,
            Object itemId, Property.ValueChangeListener listener) {
        if (listener != null && singlePropertyValueChangeListeners != null) {
            final Hashtable propertySetToListenerListMap = (Hashtable) singlePropertyValueChangeListeners
                    .get(propertyId);
            if (propertySetToListenerListMap != null) {
                final LinkedList listenerList = (LinkedList) propertySetToListenerListMap
                        .get(itemId);
                if (listenerList != null) {
                    listenerList.remove(listener);
                    if (listenerList.isEmpty()) {
                        propertySetToListenerListMap.remove(itemId);
                    }
                }
                if (propertySetToListenerListMap.isEmpty()) {
                    singlePropertyValueChangeListeners.remove(propertyId);
                }
            }
            if (singlePropertyValueChangeListeners.isEmpty()) {
                singlePropertyValueChangeListeners = null;
            }
        }
    }

    /* Internal Item and Property implementations *************************** */

    /*
     * A class implementing the com.itmill.toolkit.data.Item interface to be
     * contained in the list. @author IT Mill Ltd.
     * 
     * @version @VERSION@
     * @since 3.0
     */
    class IndexedContainerItem implements Item {

        /**
         * Item ID in the host container for this Item.
         */
        private final Object itemId;

        /**
         * Constructs a new ListItem instance and connects it to a host
         * container.
         * 
         * @param itemId
         *                the Item ID of the new Item.
         */
        private IndexedContainerItem(Object itemId) {

            // Gets the item contents from the host
            if (itemId == null) {
                throw new NullPointerException();
            }
            this.itemId = itemId;
        }

        /**
         * Gets the Property corresponding to the given Property ID stored in
         * the Item. If the Item does not contain the Property,
         * <code>null</code> is returned.
         * 
         * @param id
         *                the identifier of the Property to get.
         * @return the Property with the given ID or <code>null</code>
         */
        public Property getItemProperty(Object id) {
            return new IndexedContainerProperty(itemId, id);
        }

        /**
         * Gets the collection containing the IDs of all Properties stored in
         * the Item.
         * 
         * @return unmodifiable collection contaning IDs of the Properties
         *         stored the Item
         */
        public Collection getItemPropertyIds() {
            return Collections.unmodifiableCollection(propertyIds);
        }

        /**
         * Gets the <code>String</code> representation of the contents of the
         * Item. The format of the string is a space separated catenation of the
         * <code>String</code> representations of the Properties contained by
         * the Item.
         * 
         * @return <code>String</code> representation of the Item contents
         */
        public String toString() {
            String retValue = "";

            for (final Iterator i = propertyIds.iterator(); i.hasNext();) {
                final Object propertyId = i.next();
                retValue += getItemProperty(propertyId).toString();
                if (i.hasNext()) {
                    retValue += " ";
                }
            }

            return retValue;
        }

        /**
         * Calculates a integer hash-code for the Item that's unique inside the
         * list. Two Items inside the same list have always different
         * hash-codes, though Items in different lists may have identical
         * hash-codes.
         * 
         * @return A locally unique hash-code as integer
         */
        public int hashCode() {
            return getHost().hashCode() ^ itemId.hashCode();
        }

        /**
         * Tests if the given object is the same as the this object. Two Items
         * got from a list container with the same ID are equal.
         * 
         * @param obj
         *                an object to compare with this object
         * @return <code>true</code> if the given object is the same as this
         *         object, <code>false</code> if not
         */
        public boolean equals(Object obj) {
            if (obj == null
                    || !obj.getClass().equals(IndexedContainerItem.class)) {
                return false;
            }
            final IndexedContainerItem li = (IndexedContainerItem) obj;
            return getHost() == li.getHost() && itemId.equals(li.itemId);
        }

        /**
         * 
         * @return
         */
        private IndexedContainer getHost() {
            return IndexedContainer.this;
        }

        /**
         * Indexed container does not support adding new properties.
         * 
         * @see com.itmill.toolkit.data.Item#addProperty(Object, Property)
         */
        public boolean addItemProperty(Object id, Property property)
                throws UnsupportedOperationException {
            throw new UnsupportedOperationException("Indexed container item "
                    + "does not support adding new properties");
        }

        /**
         * Indexed container does not support removing properties.
         * 
         * @see com.itmill.toolkit.data.Item#removeProperty(Object)
         */
        public boolean removeItemProperty(Object id)
                throws UnsupportedOperationException {
            throw new UnsupportedOperationException(
                    "Indexed container item does not support property removal");
        }

    }

    /**
     * A class implementing the com.itmill.toolkit.data.Property interface to be
     * contained in the Items contained in the list.
     * 
     * @author IT Mill Ltd.
     * 
     * @version
     * @VERSION@
     * @since 3.0
     */
    private class IndexedContainerProperty implements Property,
            Property.ValueChangeNotifier {

        /**
         * ID of the Item, where the Property resides.
         */
        private final Object itemId;

        /**
         * Id of the Property.
         */
        private final Object propertyId;

        /**
         * Constructs a new ListProperty object and connect it to a ListItem and
         * a ListContainer.
         * 
         * @param itemId
         *                the ID of the Item to connect the new Property to.
         * @param propertyId
         *                the Property ID of the new Property.
         * @param host
         *                the list that contains the Item to contain the new
         *                Property.
         */
        private IndexedContainerProperty(Object itemId, Object propertyId) {
            if (itemId == null || propertyId == null) {
                throw new NullPointerException();
            }
            this.propertyId = propertyId;
            this.itemId = itemId;
        }

        /**
         * Returns the type of the Property. The methods <code>getValue</code>
         * and <code>setValue</code> must be compatible with this type: one
         * must be able to safely cast the value returned from
         * <code>getValue</code> to the given type and pass any variable
         * assignable to this type as a parameter to <code>setValue</code.
         * 
         * @return the type of the Property.
         */
        public Class getType() {
            return (Class) types.get(propertyId);
        }

        /**
         * Gets the value stored in the Property.
         * 
         * @return the value stored in the Property.
         */
        public Object getValue() {
            return ((Hashtable) items.get(itemId)).get(propertyId);
        }

        /**
         * <p>
         * Tests if the Property is in read-only mode. In read-only mode calls
         * to the method <code>setValue</code> will throw
         * <code>ReadOnlyException</code> s and will not modify the value of
         * the Property.
         * </p>
         * 
         * @return <code>true</code> if the Property is in read-only mode,
         *         <code>false</code> if it's not.
         */
        public boolean isReadOnly() {
            return readOnlyProperties.contains(this);
        }

        /**
         * Sets the Property's read-only mode to the specified status.
         * 
         * @param newStatus
         *                the new read-only status of the Property.
         */
        public void setReadOnly(boolean newStatus) {
            if (newStatus) {
                readOnlyProperties.add(this);
            } else {
                readOnlyProperties.remove(this);
            }
        }

        /**
         * Sets the value of the Property. By default this method will try to
         * assign the value directly, but if it is unassignable, it will try to
         * use the <code>String</code> constructor of the internal data type
         * to assign the value,
         * 
         * @param newValue
         *                the New value of the Property. This should be
         *                assignable to the Property's internal type or support
         *                <code>toString</code>.
         * 
         * @throws Property.ReadOnlyException
         *                 if the object is in read-only mode
         * @throws Property.ConversionException
         *                 if <code>newValue</code> can't be converted into
         *                 the Property's native type directly or through
         *                 <code>String</code>
         */
        public void setValue(Object newValue)
                throws Property.ReadOnlyException, Property.ConversionException {

            // Gets the Property set
            final Hashtable propertySet = (Hashtable) items.get(itemId);

            // Support null values on all types
            if (newValue == null) {
                propertySet.remove(propertyId);
            } else if (getType().isAssignableFrom(newValue.getClass())) {
                propertySet.put(propertyId, newValue);
            } else {
                try {

                    // Gets the string constructor
                    final Constructor constr = getType().getConstructor(
                            new Class[] { String.class });

                    // Creates new object from the string
                    propertySet.put(propertyId, constr
                            .newInstance(new Object[] { newValue.toString() }));

                } catch (final java.lang.Exception e) {
                    throw new Property.ConversionException(
                            "Conversion for value '" + newValue + "' of class "
                                    + newValue.getClass().getName() + " to "
                                    + getType().getName() + " failed");
                }
            }

            firePropertyValueChange(this);
        }

        /**
         * Returns the value of the Property in human readable textual format.
         * The return value should be assignable to the <code>setValue</code>
         * method if the Property is not in read-only mode.
         * 
         * @return <code>String</code> representation of the value stored in
         *         the Property
         */
        public String toString() {
            final Object value = getValue();
            if (value == null) {
                return null;
            }
            return value.toString();
        }

        /**
         * Calculates a integer hash-code for the Property that's unique inside
         * the Item containing the Property. Two different Properties inside the
         * same Item contained in the same list always have different
         * hash-codes, though Properties in different Items may have identical
         * hash-codes.
         * 
         * @return A locally unique hash-code as integer
         */
        public int hashCode() {
            return itemId.hashCode() ^ propertyId.hashCode()
                    ^ IndexedContainer.this.hashCode();
        }

        /**
         * Tests if the given object is the same as the this object. Two
         * Properties got from an Item with the same ID are equal.
         * 
         * @param obj
         *                an object to compare with this object
         * @return <code>true</code> if the given object is the same as this
         *         object, <code>false</code> if not
         */
        public boolean equals(Object obj) {
            if (obj == null
                    || !obj.getClass().equals(IndexedContainerProperty.class)) {
                return false;
            }
            final IndexedContainerProperty lp = (IndexedContainerProperty) obj;
            return lp.getHost() == getHost()
                    && lp.propertyId.equals(propertyId)
                    && lp.itemId.equals(itemId);
        }

        /**
         * Registers a new value change listener for this Property.
         * 
         * @param listener
         *                the new Listener to be registered.
         * @see com.itmill.toolkit.data.Property.ValueChangeNotifier#addListener(ValueChangeListener)
         */
        public void addListener(Property.ValueChangeListener listener) {
            addSinglePropertyChangeListener(propertyId, itemId, listener);
        }

        /**
         * Removes a previously registered value change listener.
         * 
         * @param listener
         *                listener to be removed
         * @see com.itmill.toolkit.data.Property.ValueChangeNotifier#removeListener(ValueChangeListener)
         */
        public void removeListener(Property.ValueChangeListener listener) {
            removeSinglePropertyChangeListener(propertyId, itemId, listener);
        }

        private IndexedContainer getHost() {
            return IndexedContainer.this;
        }

    }

    /**
     * @see com.itmill.toolkit.data.Container.Sortable#sort(java.lang.Object[],
     *      boolean[])
     */
    public synchronized void sort(Object[] propertyId, boolean[] ascending) {

        // Removes any non-sortable property ids
        final ArrayList ids = new ArrayList();
        final ArrayList orders = new ArrayList();
        final Collection sortable = getSortableContainerPropertyIds();
        for (int i = 0; i < propertyId.length; i++) {
            if (sortable.contains(propertyId[i])) {
                ids.add(propertyId[i]);
                orders.add(new Boolean(i < ascending.length ? ascending[i]
                        : true));
            }
        }

        if (ids.size() == 0) {
            return;
        }
        sortPropertyId = ids.toArray();
        sortDirection = new boolean[orders.size()];
        for (int i = 0; i < sortDirection.length; i++) {
            sortDirection[i] = ((Boolean) orders.get(i)).booleanValue();
        }

        // Sort
        Collections.sort(itemIds, this);
        if (filteredItemIds != null) {
            updateContainerFiltering();
        } else {
            fireContentsChange();
        }

        // Remove temporary references
        sortPropertyId = null;
        sortDirection = null;

    }

    /**
     * @see com.itmill.toolkit.data.Container.Sortable#getSortableContainerPropertyIds()
     */
    public Collection getSortableContainerPropertyIds() {

        final LinkedList list = new LinkedList();
        for (final Iterator i = propertyIds.iterator(); i.hasNext();) {
            final Object id = i.next();
            final Class type = getType(id);
            if (type != null && Comparable.class.isAssignableFrom(type)) {
                list.add(id);
            }
        }

        return list;
    }

    /**
     * Compares two items for sorting.
     * 
     * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
     * @see #sort((java.lang.Object[], boolean[])
     */
    public int compare(Object o1, Object o2) {

        for (int i = 0; i < sortPropertyId.length; i++) {

            // Get the compared properties
            final Property pp1 = getContainerProperty(o1, sortPropertyId[i]);
            final Property pp2 = getContainerProperty(o2, sortPropertyId[i]);

            // Get the compared values
            final Object p1 = pp1 == null ? null : pp1.getValue();
            final Object p2 = pp2 == null ? null : pp2.getValue();

            // Result of the comparison
            int r = 0;

            // Normal non-null comparison
            if (p1 != null && p2 != null) {
                if ((p1 instanceof Boolean) && (p2 instanceof Boolean)) {
                    r = p1.equals(p2) ? 0
                            : ((sortDirection[i] ? 1 : -1) * (((Boolean) p1)
                                    .booleanValue() ? 1 : -1));
                } else {
                    r = sortDirection[i] ? ((Comparable) p1).compareTo(p2)
                            : -((Comparable) p1).compareTo(p2);
                }
            }

            // If both are nulls
            else if (p1 == p2) {
                r = 0;
            } else {
                r = (sortDirection[i] ? 1 : -1) * (p1 == null ? -1 : 1);
            }

            // If order can be decided
            if (r != 0) {
                return r;
            }
        }

        return 0;
    }

    /**
     * Supports cloning of the IndexedContainer cleanly.
     * 
     * @throws CloneNotSupportedException
     *                 if an object cannot be cloned. .
     */
    public Object clone() throws CloneNotSupportedException {

        // Creates the clone
        final IndexedContainer nc = new IndexedContainer();

        // Clone the shallow properties
        nc.itemIds = itemIds != null ? (ArrayList) itemIds.clone() : null;
        nc.itemSetChangeListeners = itemSetChangeListeners != null ? (LinkedList) itemSetChangeListeners
                .clone()
                : null;
        nc.propertyIds = propertyIds != null ? (ArrayList) propertyIds.clone()
                : null;
        nc.propertySetChangeListeners = propertySetChangeListeners != null ? (LinkedList) propertySetChangeListeners
                .clone()
                : null;
        nc.propertyValueChangeListeners = propertyValueChangeListeners != null ? (LinkedList) propertyValueChangeListeners
                .clone()
                : null;
        nc.readOnlyProperties = readOnlyProperties != null ? (HashSet) readOnlyProperties
                .clone()
                : null;
        nc.singlePropertyValueChangeListeners = singlePropertyValueChangeListeners != null ? (Hashtable) singlePropertyValueChangeListeners
                .clone()
                : null;
        nc.sortDirection = sortDirection != null ? (boolean[]) sortDirection
                .clone() : null;
        nc.sortPropertyId = sortPropertyId != null ? (Object[]) sortPropertyId
                .clone() : null;
        nc.types = types != null ? (Hashtable) types.clone() : null;

        nc.filters = filters == null ? null : (HashSet) filters.clone();

        nc.filteredItemIds = filteredItemIds == null ? null
                : (LinkedHashSet) filteredItemIds.clone();

        // Clone property-values
        if (items == null) {
            nc.items = null;
        } else {
            nc.items = new Hashtable();
            for (final Iterator i = items.keySet().iterator(); i.hasNext();) {
                final Object id = i.next();
                final Hashtable it = (Hashtable) items.get(id);
                nc.items.put(id, it.clone());
            }
        }

        return nc;
    }

    /**
     * @see java.lang.Object#equals(java.lang.Object)
     */
    public boolean equals(Object obj) {

        // Only ones of the objects of the same class can be equal
        if (!(obj instanceof IndexedContainer)) {
            return false;
        }
        final IndexedContainer o = (IndexedContainer) obj;

        // Checks the properties one by one
        if (itemIds != o.itemIds && o.itemIds != null
                && !o.itemIds.equals(itemIds)) {
            return false;
        }
        if (filters != o.filters && o.filters != null
                && !o.filters.equals(filters)) {
            return false;
        }
        if (items != o.items && o.items != null && !o.items.equals(items)) {
            return false;
        }
        if (itemSetChangeListeners != o.itemSetChangeListeners
                && o.itemSetChangeListeners != null
                && !o.itemSetChangeListeners.equals(itemSetChangeListeners)) {
            return false;
        }
        if (propertyIds != o.propertyIds && o.propertyIds != null
                && !o.propertyIds.equals(propertyIds)) {
            return false;
        }
        if (propertySetChangeListeners != o.propertySetChangeListeners
                && o.propertySetChangeListeners != null
                && !o.propertySetChangeListeners
                        .equals(propertySetChangeListeners)) {
            return false;
        }
        if (propertyValueChangeListeners != o.propertyValueChangeListeners
                && o.propertyValueChangeListeners != null
                && !o.propertyValueChangeListeners
                        .equals(propertyValueChangeListeners)) {
            return false;
        }
        if (readOnlyProperties != o.readOnlyProperties
                && o.readOnlyProperties != null
                && !o.readOnlyProperties.equals(readOnlyProperties)) {
            return false;
        }
        if (singlePropertyValueChangeListeners != o.singlePropertyValueChangeListeners
                && o.singlePropertyValueChangeListeners != null
                && !o.singlePropertyValueChangeListeners
                        .equals(singlePropertyValueChangeListeners)) {
            return false;
        }
        if (sortDirection != o.sortDirection && o.sortDirection != null
                && !o.sortDirection.equals(sortDirection)) {
            return false;
        }
        if (sortPropertyId != o.sortPropertyId && o.sortPropertyId != null
                && !o.sortPropertyId.equals(sortPropertyId)) {
            return false;
        }
        if (types != o.types && o.types != null && !o.types.equals(types)) {
            return false;
        }

        return true;
    }

    /**
     * @see java.lang.Object#hashCode()
     */
    public int hashCode() {

        // The hash-code is calculated as combination hash of the members
        return (itemIds != null ? itemIds.hashCode() : 0)
                ^ (items != null ? items.hashCode() : 0)
                ^ (filters != null ? filters.hashCode() : 0)
                ^ (itemSetChangeListeners != null ? itemSetChangeListeners
                        .hashCode() : 0)
                ^ (propertyIds != null ? propertyIds.hashCode() : 0)
                ^ (propertySetChangeListeners != null ? propertySetChangeListeners
                        .hashCode()
                        : 0)
                ^ (propertyValueChangeListeners != null ? propertyValueChangeListeners
                        .hashCode()
                        : 0)
                ^ (readOnlyProperties != null ? readOnlyProperties.hashCode()
                        : 0)
                ^ (singlePropertyValueChangeListeners != null ? singlePropertyValueChangeListeners
                        .hashCode()
                        : 0)
                ^ (sortPropertyId != null ? sortPropertyId.hashCode() : 0)
                ^ (types != null ? types.hashCode() : 0)
                ^ (sortDirection != null ? sortDirection.hashCode() : 0);
    }

    private class Filter {
        Object propertyId;
        String filterString;
        boolean ignoreCase;
        boolean onlyMatchPrefix;

        Filter(Object propertyId, String filterString, boolean ignoreCase,
                boolean onlyMatchPrefix) {
            this.propertyId = propertyId;
            ;
            this.filterString = filterString;
            this.ignoreCase = ignoreCase;
            this.onlyMatchPrefix = onlyMatchPrefix;
        }

        public boolean equals(Object obj) {

            // Only ones of the objects of the same class can be equal
            if (!(obj instanceof Filter)) {
                return false;
            }
            final Filter o = (Filter) obj;

            // Checks the properties one by one
            if (propertyId != o.propertyId && o.propertyId != null
                    && !o.propertyId.equals(propertyId)) {
                return false;
            }
            if (filterString != o.filterString && o.filterString != null
                    && !o.filterString.equals(filterString)) {
                return false;
            }
            if (ignoreCase != o.ignoreCase) {
                return false;
            }
            if (onlyMatchPrefix != o.onlyMatchPrefix) {
                return false;
            }

            return true;
        }

        public int hashCode() {
            return (propertyId != null ? propertyId.hashCode() : 0)
                    ^ (filterString != null ? filterString.hashCode() : 0);
        }

    }

    public void addContainerFilter(Object propertyId, String filterString,
            boolean ignoreCase, boolean onlyMatchPrefix) {
        if (filters == null) {
            filters = new HashSet();
        }
        filters.add(new Filter(propertyId, filterString, ignoreCase,
                onlyMatchPrefix));
        updateContainerFiltering();
    }

    public void removeAllContainerFilters() {
        if (filters == null) {
            return;
        }
        filters.clear();
        updateContainerFiltering();
    }

    public void removeContainerFilters(Object propertyId) {
        if (filters == null || propertyId == null) {
            return;
        }
        for (final Iterator i = filters.iterator(); i.hasNext();) {
            final Filter f = (Filter) i.next();
            if (propertyId.equals(f.propertyId)) {
                i.remove();
            }
        }
        updateContainerFiltering();
    }

    private void updateContainerFiltering() {

        // Clearing filters?
        if (filters == null || filters.isEmpty()) {
            filteredItemIds = null;
            if (filters != null) {
                filters = null;
                fireContentsChange();
            }
            return;
        }

        // Reset filteres list
        if (filteredItemIds == null) {
            filteredItemIds = new LinkedHashSet();
        } else {
            filteredItemIds.clear();
        }

        // Filter
        for (final Iterator i = itemIds.iterator(); i.hasNext();) {
            final Object id = i.next();
            if (passesFilters(new IndexedContainerItem(id))) {
                filteredItemIds.add(id);
            }
        }

        fireContentsChange();
    }

    private boolean passesFilters(Item item) {
        if (filters == null) {
            return true;
        }
        if (item == null) {
            return false;
        }
        for (final Iterator i = filters.iterator(); i.hasNext();) {
            final Filter f = (Filter) i.next();
            final String s1 = f.ignoreCase ? f.filterString.toLowerCase()
                    : f.filterString;
            final Property p = item.getItemProperty(f.propertyId);
            if (p == null || p.toString() == null) {
                return false;
            }
            final String s2 = f.ignoreCase ? p.toString().toLowerCase() : p
                    .toString();
            if (f.onlyMatchPrefix) {
                if (s2.indexOf(s1) != 0) {
                    return false;
                }
            } else {
                if (s2.indexOf(s1) < 0) {
                    return false;
                }
            }
        }
        return true;
    }

}