Copyright (c) 2000, 2014 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2014 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.core.internal.dtree;

import org.eclipse.core.runtime.IPath;

A DataDeltaNode contains information that represents the differences
between itself and a node in another tree.  Refer to the DeltaDataTree
API and comments for details.
See Also:
DeltaDataTree/**
 * A <code>DataDeltaNode</code> contains information that represents the differences
 * between itself and a node in another tree.  Refer to the <code>DeltaDataTree</code>
 * API and comments for details.
 *
 * @see DeltaDataTree
 */
public class DataDeltaNode extends DataTreeNode {
	
Creates a node with the given name and data, but with no children.
/**
	 * Creates a node with the given name and data, but with no children.
	 */
	DataDeltaNode(String name, Object data) {
		super(name, data);
	}

	
Creates a node with the given name, data and children.
/**
	 * Creates a node with the given name, data and children.
	 */
	DataDeltaNode(String name, Object data, AbstractDataTreeNode[] children) {
		super(name, data, children);
	}

	
See Also:
asBackwardDelta.asBackwardDelta(DeltaDataTree, DeltaDataTree, IPath)/**
	 * @see AbstractDataTreeNode#asBackwardDelta(DeltaDataTree, DeltaDataTree, IPath)
	 */
	@Override
	AbstractDataTreeNode asBackwardDelta(DeltaDataTree myTree, DeltaDataTree parentTree, IPath key) {
		AbstractDataTreeNode[] newChildren;
		if (children.length == 0) {
			newChildren = NO_CHILDREN;
		} else {
			newChildren = new AbstractDataTreeNode[children.length];
			for (int i = children.length; --i >= 0;) {
				newChildren[i] = children[i].asBackwardDelta(myTree, parentTree, key.append(children[i].getName()));
			}
		}
		return new DataDeltaNode(name, parentTree.getData(key), newChildren);
	}

	@Override
	AbstractDataTreeNode compareWithParent(IPath key, DeltaDataTree parent, IComparator comparator) {
		AbstractDataTreeNode[] comparedChildren = compareWithParent(children, key, parent, comparator);
		Object oldData = parent.getData(key);
		Object newData = data;
		/* don't compare data of root */
		int userComparison = 0;
		if (key != parent.rootKey()) {
			/* allow client to specify user comparison bits */
			userComparison = comparator.compare(oldData, newData);
		}
		return new DataTreeNode(key.lastSegment(), new NodeComparison(oldData, newData, NodeComparison.K_CHANGED, userComparison), comparedChildren);
	}

	
Creates and returns a new copy of the receiver.  Makes a deep copy of
children, but a shallow copy of name and data.
/**
	 * Creates and returns a new copy of the receiver.  Makes a deep copy of
	 * children, but a shallow copy of name and data.
	 */
	@Override
	AbstractDataTreeNode copy() {
		AbstractDataTreeNode[] childrenCopy;
		if (children.length == 0) {
			childrenCopy = NO_CHILDREN;
		} else {
			childrenCopy = new AbstractDataTreeNode[children.length];
			System.arraycopy(children, 0, childrenCopy, 0, children.length);
		}
		return new DataDeltaNode(name, data, childrenCopy);
	}

	
Returns true if the receiver represents delta information,
false if it represents the complete information.
/**
	 * Returns true if the receiver represents delta information,
	 * false if it represents the complete information.
	 */
	@Override
	boolean isDelta() {
		return true;
	}

	
Simplifies the given node, and answers its replacement.
/**
	 * Simplifies the given node, and answers its replacement.
	 */
	@Override
	AbstractDataTreeNode simplifyWithParent(IPath key, DeltaDataTree parent, IComparator comparer) {
		AbstractDataTreeNode[] simplifiedChildren = simplifyWithParent(children, key, parent, comparer);
		/* don't compare root nodes */
		if (!key.isRoot() && comparer.compare(parent.getData(key), data) == 0)
			return new NoDataDeltaNode(name, simplifiedChildren);
		return new DataDeltaNode(name, data, simplifiedChildren);
	}

	
Returns a unicode representation of the node.  This method is used
for debugging purposes only (no NLS support needed)
/**
	 * Returns a unicode representation of the node.  This method is used
	 * for debugging purposes only (no NLS support needed)
	 */
	@Override
	public String toString() {
		return "a DataDeltaNode(" + this.getName() + ") with " + getChildren().length + " children."; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
	}

	
Returns a constant describing the type of node.
/**
	 * Returns a constant describing the type of node.
	 */
	@Override
	int type() {
		return T_DELTA_NODE;
	}
}