/*
* Copyright 2000-2014 Vaadin Ltd.
*
* 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 com.vaadin.data.util;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import com.vaadin.data.Container;
import com.vaadin.data.Item;
import com.vaadin.data.Property;
/**
* <p>
* A wrapper class for adding external hierarchy to containers not implementing
* the {@link com.vaadin.data.Container.Hierarchical} interface.
* </p>
*
* <p>
* If the wrapped container is changed directly (that is, not through the
* wrapper), and does not implement Container.ItemSetChangeNotifier and/or
* Container.PropertySetChangeNotifier the hierarchy information must be updated
* with the {@link #updateHierarchicalWrapper()} method.
* </p>
*
* @author Vaadin Ltd.
* @since 3.0
*/
@SuppressWarnings("serial")
public class ContainerHierarchicalWrapper implements Container.Hierarchical,
Container.ItemSetChangeNotifier, Container.PropertySetChangeNotifier {
/** The wrapped container */
private final Container container;
/** Set of IDs of those contained Items that can't have children. */
private HashSet<Object> noChildrenAllowed = null;
/** Mapping from Item ID to parent Item ID */
private Hashtable<Object, Object> parent = null;
/** Mapping from Item ID to a list of child IDs */
private Hashtable<Object, LinkedList<Object>> children = null;
/** List that contains all root elements of the container. */
private LinkedHashSet<Object> roots = null;
/** Is the wrapped container hierarchical by itself ? */
private boolean hierarchical;
/**
* A comparator that sorts the listed items before other items. Otherwise,
* the order is undefined.
*/
private static class ListedItemsFirstComparator implements
Comparator<Object>, Serializable {
private final Collection<?> itemIds;
private ListedItemsFirstComparator(Collection<?> itemIds) {
this.itemIds = itemIds;
}
@Override
public int compare(Object o1, Object o2) {
if (o1.equals(o2)) {
return 0;
}
for (Object id : itemIds) {
if (id == o1) {
return -1;
} else if (id == o2) {
return 1;
}
}
return 0;
}
}
/**
* Constructs a new hierarchical wrapper for an existing Container. Works
* even if the to-be-wrapped container already implements the
* <code>Container.Hierarchical</code> interface.
*
* @param toBeWrapped
* the container that needs to be accessed hierarchically
* @see #updateHierarchicalWrapper()
*/
public ContainerHierarchicalWrapper(Container toBeWrapped) {
container = toBeWrapped;
hierarchical = container instanceof Container.Hierarchical;
// Check arguments
if (container == null) {
throw new NullPointerException("Null can not be wrapped");
}
// Create initial order if needed
if (!hierarchical) {
noChildrenAllowed = new HashSet<Object>();
parent = new Hashtable<Object, Object>();
children = new Hashtable<Object, LinkedList<Object>>();
roots = new LinkedHashSet<Object>(container.getItemIds());
}
updateHierarchicalWrapper();
}
/**
* Updates the wrapper's internal hierarchy data to include all Items in the
* underlying container. If the contents of the wrapped container change
* without the wrapper's knowledge, this method needs to be called to update
* the hierarchy information of the Items.
*/
public void updateHierarchicalWrapper() {
if (!hierarchical) {
// Recreate hierarchy and data structures if missing
if (noChildrenAllowed == null || parent == null || children == null
|| roots == null) {
noChildrenAllowed = new HashSet<Object>();
parent = new Hashtable<Object, Object>();
children = new Hashtable<Object, LinkedList<Object>>();
roots = new LinkedHashSet<Object>(container.getItemIds());
}
// Check that the hierarchy is up-to-date
else {
// ensure order of root and child lists is same as in wrapped
// container
Collection<?> itemIds = container.getItemIds();
Comparator<Object> basedOnOrderFromWrappedContainer = new ListedItemsFirstComparator(
itemIds);
// Calculate the set of all items in the hierarchy
final HashSet<Object> s = new HashSet<Object>();
s.addAll(parent.keySet());
s.addAll(children.keySet());
s.addAll(roots);
// Remove unnecessary items
for (final Iterator<Object> i = s.iterator(); i.hasNext();) {
final Object id = i.next();
if (!container.containsId(id)) {
removeFromHierarchyWrapper(id);
}
}
// Add all the missing items
final Collection<?> ids = container.getItemIds();
for (final Iterator<?> i = ids.iterator(); i.hasNext();) {
final Object id = i.next();
if (!s.contains(id)) {
addToHierarchyWrapper(id);
s.add(id);
}
}
Object[] array = roots.toArray();
Arrays.sort(array, basedOnOrderFromWrappedContainer);
roots = new LinkedHashSet<Object>();
for (int i = 0; i < array.length; i++) {
roots.add(array[i]);
}
for (Object object : children.keySet()) {
LinkedList<Object> object2 = children.get(object);
Collections.sort(object2, basedOnOrderFromWrappedContainer);
}
}
}
}
/**
* Removes the specified Item from the wrapper's internal hierarchy
* structure.
* <p>
* Note : The Item is not removed from the underlying Container.
* </p>
*
* @param itemId
* the ID of the item to remove from the hierarchy.
*/
private void removeFromHierarchyWrapper(Object itemId) {
LinkedList<Object> oprhanedChildren = children.remove(itemId);
if (oprhanedChildren != null) {
for (Object object : oprhanedChildren) {
// make orphaned children root nodes
setParent(object, null);
}
}
roots.remove(itemId);
final Object p = parent.get(itemId);
if (p != null) {
final LinkedList<Object> c = children.get(p);
if (c != null) {
c.remove(itemId);
}
}
parent.remove(itemId);
noChildrenAllowed.remove(itemId);
}
/**
* Adds the specified Item specified to the internal hierarchy structure.
* The new item is added as a root Item. The underlying container is not
* modified.
*
* @param itemId
* the ID of the item to add to the hierarchy.
*/
private void addToHierarchyWrapper(Object itemId) {
roots.add(itemId);
}
/*
* Can the specified Item have any children? Don't add a JavaDoc comment
* here, we use the default documentation from implemented interface.
*/
@Override
public boolean areChildrenAllowed(Object itemId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container)
.areChildrenAllowed(itemId);
}
if (noChildrenAllowed.contains(itemId)) {
return false;
}
return containsId(itemId);
}
/*
* Gets the IDs of the children of the specified Item. Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public Collection<?> getChildren(Object itemId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).getChildren(itemId);
}
final Collection<?> c = children.get(itemId);
if (c == null) {
return null;
}
return Collections.unmodifiableCollection(c);
}
/*
* Gets the ID of the parent of the specified Item. Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public Object getParent(Object itemId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).getParent(itemId);
}
return parent.get(itemId);
}
/*
* Is the Item corresponding to the given ID a leaf node? Don't add a
* JavaDoc comment here, we use the default documentation from implemented
* interface.
*/
@Override
public boolean hasChildren(Object itemId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).hasChildren(itemId);
}
LinkedList<Object> list = children.get(itemId);
return (list != null && !list.isEmpty());
}
/*
* Is the Item corresponding to the given ID a root node? Don't add a
* JavaDoc comment here, we use the default documentation from implemented
* interface.
*/
@Override
public boolean isRoot(Object itemId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).isRoot(itemId);
}
if (parent.containsKey(itemId)) {
return false;
}
return containsId(itemId);
}
/*
* Gets the IDs of the root elements in the container. Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public Collection<?> rootItemIds() {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).rootItemIds();
}
return Collections.unmodifiableCollection(roots);
}
/**
* <p>
* Sets the given Item's capability to have children. If the Item identified
* with the itemId already has children and the areChildrenAllowed is false
* this method fails and <code>false</code> is returned; the children must
* be first explicitly removed with
* {@link #setParent(Object itemId, Object newParentId)} or
* {@link com.vaadin.data.Container#removeItem(Object itemId)}.
* </p>
*
* @param itemId
* the ID of the Item in the container whose child capability is
* to be set.
* @param childrenAllowed
* the boolean value specifying if the Item can have children or
* not.
* @return <code>true</code> if the operation succeeded, <code>false</code>
* if not
*/
@Override
public boolean setChildrenAllowed(Object itemId, boolean childrenAllowed) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).setChildrenAllowed(
itemId, childrenAllowed);
}
// Check that the item is in the container
if (!containsId(itemId)) {
return false;
}
// Update status
if (childrenAllowed) {
noChildrenAllowed.remove(itemId);
} else {
noChildrenAllowed.add(itemId);
}
return true;
}
/**
* <p>
* Sets the parent of an Item. The new parent item must exist and be able to
* have children. (<code>canHaveChildren(newParentId) == true</code>). It is
* also possible to detach a node from the hierarchy (and thus make it root)
* by setting the parent <code>null</code>.
* </p>
*
* @param itemId
* the ID of the item to be set as the child of the Item
* identified with newParentId.
* @param newParentId
* the ID of the Item that's to be the new parent of the Item
* identified with itemId.
* @return <code>true</code> if the operation succeeded, <code>false</code>
* if not
*/
@Override
public boolean setParent(Object itemId, Object newParentId) {
// If the wrapped container implements the method directly, use it
if (hierarchical) {
return ((Container.Hierarchical) container).setParent(itemId,
newParentId);
}
// Check that the item is in the container
if (!containsId(itemId)) {
return false;
}
// Get the old parent
final Object oldParentId = parent.get(itemId);
// Check if no change is necessary
if ((newParentId == null && oldParentId == null)
|| (newParentId != null && newParentId.equals(oldParentId))) {
return true;
}
// Making root
if (newParentId == null) {
// Remove from old parents children list
final LinkedList<Object> l = children.get(oldParentId);
if (l != null) {
l.remove(itemId);
if (l.isEmpty()) {
children.remove(itemId);
}
}
// Add to be a root
roots.add(itemId);
// Update parent
parent.remove(itemId);
return true;
}
// Check that the new parent exists in container and can have
// children
if (!containsId(newParentId) || noChildrenAllowed.contains(newParentId)) {
return false;
}
// Check that setting parent doesn't result to a loop
Object o = newParentId;
while (o != null && !o.equals(itemId)) {
o = parent.get(o);
}
if (o != null) {
return false;
}
// Update parent
parent.put(itemId, newParentId);
LinkedList<Object> pcl = children.get(newParentId);
if (pcl == null) {
pcl = new LinkedList<Object>();
children.put(newParentId, pcl);
}
pcl.add(itemId);
// Remove from old parent or root
if (oldParentId == null) {
roots.remove(itemId);
} else {
final LinkedList<Object> l = children.get(oldParentId);
if (l != null) {
l.remove(itemId);
if (l.isEmpty()) {
children.remove(oldParentId);
}
}
}
return true;
}
/**
* Creates a new Item into the Container, assigns it an automatic ID, and
* adds it to the hierarchy.
*
* @return the autogenerated ID of the new Item or <code>null</code> if the
* operation failed
* @throws UnsupportedOperationException
* if the addItem is not supported.
*/
@Override
public Object addItem() throws UnsupportedOperationException {
final Object id = container.addItem();
if (!hierarchical && id != null) {
addToHierarchyWrapper(id);
}
return id;
}
/**
* Adds a new Item by its ID to the underlying container and to the
* hierarchy.
*
* @param itemId
* the ID of the Item to be created.
* @return the added Item or <code>null</code> if the operation failed.
* @throws UnsupportedOperationException
* if the addItem is not supported.
*/
@Override
public Item addItem(Object itemId) throws UnsupportedOperationException {
// Null ids are not accepted
if (itemId == null) {
throw new NullPointerException("Container item id can not be null");
}
final Item item = container.addItem(itemId);
if (!hierarchical && item != null) {
addToHierarchyWrapper(itemId);
}
return item;
}
/**
* Removes all items from the underlying container and from the hierarcy.
*
* @return <code>true</code> if the operation succeeded, <code>false</code>
* if not
* @throws UnsupportedOperationException
* if the removeAllItems is not supported.
*/
@Override
public boolean removeAllItems() throws UnsupportedOperationException {
final boolean success = container.removeAllItems();
if (!hierarchical && success) {
roots.clear();
parent.clear();
children.clear();
noChildrenAllowed.clear();
}
return success;
}
/**
* Removes an Item specified by the itemId from the underlying container and
* from the hierarchy.
*
* @param itemId
* the ID of the Item to be removed.
* @return <code>true</code> if the operation succeeded, <code>false</code>
* if not
* @throws UnsupportedOperationException
* if the removeItem is not supported.
*/
@Override
public boolean removeItem(Object itemId)
throws UnsupportedOperationException {
final boolean success = container.removeItem(itemId);
if (!hierarchical && success) {
removeFromHierarchyWrapper(itemId);
}
return success;
}
/**
* Removes the Item identified by given itemId and all its children.
*
* @see #removeItem(Object)
* @param itemId
* the identifier of the Item to be removed
* @return true if the operation succeeded
*/
public boolean removeItemRecursively(Object itemId) {
return HierarchicalContainer.removeItemRecursively(this, itemId);
}
/**
* Adds a new Property to all Items in the Container.
*
* @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
* @throws UnsupportedOperationException
* if the addContainerProperty is not supported.
*/
@Override
public boolean addContainerProperty(Object propertyId, Class<?> type,
Object defaultValue) throws UnsupportedOperationException {
return container.addContainerProperty(propertyId, type, defaultValue);
}
/**
* Removes the specified Property from the underlying container and from the
* hierarchy.
* <p>
* Note : The Property will be removed from all Items in the Container.
* </p>
*
* @param propertyId
* the ID of the Property to remove.
* @return <code>true</code> if the operation succeeded, <code>false</code>
* if not
* @throws UnsupportedOperationException
* if the removeContainerProperty is not supported.
*/
@Override
public boolean removeContainerProperty(Object propertyId)
throws UnsupportedOperationException {
return container.removeContainerProperty(propertyId);
}
/*
* Does the container contain the specified Item? Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public boolean containsId(Object itemId) {
return container.containsId(itemId);
}
/*
* Gets the specified Item from the container. Don't add a JavaDoc comment
* here, we use the default documentation from implemented interface.
*/
@Override
public Item getItem(Object itemId) {
return container.getItem(itemId);
}
/*
* Gets the ID's of all Items stored in the Container Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public Collection<?> getItemIds() {
return container.getItemIds();
}
/*
* Gets the Property identified by the given itemId and propertyId from the
* Container Don't add a JavaDoc comment here, we use the default
* documentation from implemented interface.
*/
@Override
public Property getContainerProperty(Object itemId, Object propertyId) {
return container.getContainerProperty(itemId, propertyId);
}
/*
* Gets the ID's of all Properties stored in the Container Don't add a
* JavaDoc comment here, we use the default documentation from implemented
* interface.
*/
@Override
public Collection<?> getContainerPropertyIds() {
return container.getContainerPropertyIds();
}
/*
* Gets the data type of all Properties identified by the given Property ID.
* Don't add a JavaDoc comment here, we use the default documentation from
* implemented interface.
*/
@Override
public Class<?> getType(Object propertyId) {
return container.getType(propertyId);
}
/*
* Gets the number of Items in the Container. Don't add a JavaDoc comment
* here, we use the default documentation from implemented interface.
*/
@Override
public int size() {
int size = container.size();
assert size >= 0;
return size;
}
/*
* Registers a new Item set change listener for this Container. Don't add a
* JavaDoc comment here, we use the default documentation from implemented
* interface.
*/
@Override
public void addItemSetChangeListener(
Container.ItemSetChangeListener listener) {
if (container instanceof Container.ItemSetChangeNotifier) {
((Container.ItemSetChangeNotifier) container)
.addItemSetChangeListener(new PiggybackListener(listener));
}
}
/**
* @deprecated As of 7.0, replaced by
* {@link #addItemSetChangeListener(com.vaadin.data.Container.ItemSetChangeListener)}
**/
@Override
@Deprecated
public void addListener(Container.ItemSetChangeListener listener) {
addItemSetChangeListener(listener);
}
/*
* Removes a Item set change listener from the object. Don't add a JavaDoc
* comment here, we use the default documentation from implemented
* interface.
*/
@Override
public void removeItemSetChangeListener(
Container.ItemSetChangeListener listener) {
if (container instanceof Container.ItemSetChangeNotifier) {
((Container.ItemSetChangeNotifier) container)
.removeItemSetChangeListener(new PiggybackListener(listener));
}
}
/**
* @deprecated As of 7.0, replaced by
* {@link #removeItemSetChangeListener(com.vaadin.data.Container.ItemSetChangeListener)}
**/
@Override
@Deprecated
public void removeListener(Container.ItemSetChangeListener listener) {
removeItemSetChangeListener(listener);
}
/*
* Registers a new Property set change listener for this Container. Don't
* add a JavaDoc comment here, we use the default documentation from
* implemented interface.
*/
@Override
public void addPropertySetChangeListener(
Container.PropertySetChangeListener listener) {
if (container instanceof Container.PropertySetChangeNotifier) {
((Container.PropertySetChangeNotifier) container)
.addPropertySetChangeListener(new PiggybackListener(
listener));
}
}
/**
* @deprecated As of 7.0, replaced by
* {@link #addPropertySetChangeListener(com.vaadin.data.Container.PropertySetChangeListener)}
**/
@Override
@Deprecated
public void addListener(Container.PropertySetChangeListener listener) {
addPropertySetChangeListener(listener);
}
/*
* Removes a Property set change listener from the object. Don't add a
* JavaDoc comment here, we use the default documentation from implemented
* interface.
*/
@Override
public void removePropertySetChangeListener(
Container.PropertySetChangeListener listener) {
if (container instanceof Container.PropertySetChangeNotifier) {
((Container.PropertySetChangeNotifier) container)
.removePropertySetChangeListener(new PiggybackListener(
listener));
}
}
/**
* @deprecated As of 7.0, replaced by
* {@link #removePropertySetChangeListener(com.vaadin.data.Container.PropertySetChangeListener)}
**/
@Override
@Deprecated
public void removeListener(Container.PropertySetChangeListener listener) {
removePropertySetChangeListener(listener);
}
/**
* This listener 'piggybacks' on the real listener in order to update the
* wrapper when needed. It proxies equals() and hashCode() to the real
* listener so that the correct listener gets removed.
*
*/
private class PiggybackListener implements
Container.PropertySetChangeListener,
Container.ItemSetChangeListener {
Object listener;
public PiggybackListener(Object realListener) {
listener = realListener;
}
@Override
public void containerItemSetChange(ItemSetChangeEvent event) {
updateHierarchicalWrapper();
((Container.ItemSetChangeListener) listener)
.containerItemSetChange(event);
}
@Override
public void containerPropertySetChange(PropertySetChangeEvent event) {
updateHierarchicalWrapper();
((Container.PropertySetChangeListener) listener)
.containerPropertySetChange(event);
}
@Override
public boolean equals(Object obj) {
return obj == listener || (obj != null && obj.equals(listener));
}
@Override
public int hashCode() {
return listener.hashCode();
}
}
}