1420 行
37 KiB
JavaScript
1420 行
37 KiB
JavaScript
// Copyright 2011 David Galles, University of San Francisco. All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without modification, are
|
|
// permitted provided that the following conditions are met:
|
|
//
|
|
// 1. Redistributions of source code must retain the above copyright notice, this list of
|
|
// conditions and the following disclaimer.
|
|
//
|
|
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
|
|
// of conditions and the following disclaimer in the documentation and/or other materials
|
|
// provided with the distribution.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND ANY EXPRESS OR IMPLIED
|
|
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
|
// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR
|
|
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
|
|
// ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
|
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
|
|
// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
//
|
|
// The views and conclusions contained in the software and documentation are those of the
|
|
// authors and should not be interpreted as representing official policies, either expressed
|
|
// or implied, of the University of San Francisco
|
|
|
|
var FIRST_PRINT_POS_X = 50;
|
|
var PRINT_VERTICAL_GAP = 20;
|
|
var PRINT_MAX = 990;
|
|
var PRINT_HORIZONTAL_GAP = 50;
|
|
|
|
var MIN_MAX_DEGREE = 3;
|
|
var MAX_MAX_DEGREE = 7;
|
|
|
|
var HEIGHT_DELTA = 50;
|
|
var NODE_SPACING = 15;
|
|
var STARTING_Y = 30;
|
|
var WIDTH_PER_ELEM = 40;
|
|
var NODE_HEIGHT = 20;
|
|
|
|
var MESSAGE_X = 5;
|
|
var MESSAGE_Y = 10;
|
|
|
|
var LINK_COLOR = "#007700";
|
|
var HIGHLIGHT_CIRCLE_COLOR = "#007700";
|
|
var FOREGROUND_COLOR = "#007700";
|
|
var BACKGROUND_COLOR = "#EEFFEE";
|
|
var PRINT_COLOR = FOREGROUND_COLOR;
|
|
|
|
|
|
|
|
function BPlusTree(am, w, h)
|
|
{
|
|
this.init(am, w, h);
|
|
|
|
}
|
|
|
|
BPlusTree.prototype = new Algorithm();
|
|
BPlusTree.prototype.varructor = BPlusTree;
|
|
BPlusTree.superclass = Algorithm.prototype;
|
|
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.init = function(am, w, h)
|
|
{
|
|
BPlusTree.superclass.init.call(this, am, w, h);
|
|
this.nextIndex = 0;
|
|
|
|
this.preemptiveSplit = false
|
|
|
|
this.starting_x = w / 2;
|
|
|
|
this.addControls();
|
|
|
|
|
|
this.max_keys = 2;
|
|
this.min_keys = 1;
|
|
this.split_index = 1;
|
|
|
|
this.max_degree = 3;
|
|
|
|
|
|
|
|
|
|
this.messageID = this.nextIndex++;
|
|
this.cmd("CreateLabel", this.messageID, "", MESSAGE_X, MESSAGE_Y, 0);
|
|
this.moveLabel1ID = this.nextIndex++;
|
|
this.moveLabel2ID = this.nextIndex++;
|
|
|
|
animationManager.StartNewAnimation(this.commands);
|
|
animationManager.skipForward();
|
|
animationManager.clearHistory();
|
|
this.commands = new Array();
|
|
|
|
this.first_print_pos_y = h - 3 * PRINT_VERTICAL_GAP;
|
|
|
|
|
|
this.xPosOfNextLabel = 100;
|
|
this.yPosOfNextLabel = 200;
|
|
}
|
|
|
|
BPlusTree.prototype.addControls = function()
|
|
{
|
|
this.controls = [];
|
|
|
|
this.insertField = addControlToAlgorithmBar("Text", "");
|
|
this.insertField.onkeydown = this.returnSubmit(this.insertField, this.insertCallback.bind(this), 4);
|
|
this.controls.push(this.insertField);
|
|
|
|
this.insertButton = addControlToAlgorithmBar("Button", "添加");
|
|
this.insertButton.onclick = this.insertCallback.bind(this);
|
|
this.controls.push(this.insertButton);
|
|
|
|
this.deleteField = addControlToAlgorithmBar("Text", "");
|
|
this.deleteField.onkeydown = this.returnSubmit(this.deleteField, this.deleteCallback.bind(this), 4);
|
|
this.controls.push(this.deleteField);
|
|
|
|
this.deleteButton = addControlToAlgorithmBar("Button", "删除");
|
|
this.deleteButton.onclick = this.deleteCallback.bind(this);
|
|
this.controls.push(this.deleteButton);
|
|
|
|
this.findField = addControlToAlgorithmBar("Text", "");
|
|
this.findField.onkeydown = this.returnSubmit(this.findField, this.findCallback.bind(this), 4);
|
|
this.controls.push(this.findField);
|
|
|
|
this.findButton = addControlToAlgorithmBar("Button", "搜索");
|
|
this.findButton.onclick = this.findCallback.bind(this);
|
|
this.controls.push(this.findButton);
|
|
|
|
this.printButton = addControlToAlgorithmBar("Button", "打印");
|
|
this.printButton.onclick = this.printCallback.bind(this);
|
|
this.controls.push(this.printButton);
|
|
|
|
this.clearButton = addControlToAlgorithmBar("Button", "Clear");
|
|
this.clearButton.onclick = this.clearCallback.bind(this);
|
|
this.controls.push(this.clearButton);
|
|
|
|
var i;
|
|
radioButtonNames = [];
|
|
for (i = MIN_MAX_DEGREE; i <= MAX_MAX_DEGREE; i++)
|
|
{
|
|
radioButtonNames.push("Max. Degree = " + String(i));
|
|
}
|
|
|
|
this.maxDegreeRadioButtons = addRadioButtonGroupToAlgorithmBar(radioButtonNames, "MaxDegree");
|
|
|
|
this.maxDegreeRadioButtons[0].checked = true;
|
|
for(i = 0; i < this.maxDegreeRadioButtons.length; i++)
|
|
{
|
|
this.maxDegreeRadioButtons[i].onclick = this.maxDegreeChangedHandler.bind(this,i+MIN_MAX_DEGREE);
|
|
}
|
|
|
|
|
|
// this.premptiveSplitBox = addCheckboxToAlgorithmBar("Preemtive Split / Merge (Even max degree only)");
|
|
// this.premptiveSplitBox.onclick = this.premtiveSplitCallback.bind(this);
|
|
|
|
|
|
// Other buttons ...
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.reset = function()
|
|
{
|
|
this.nextIndex = 3;
|
|
this.max_degree = 3;
|
|
this.max_keys = 2;
|
|
this.min_keys = 1;
|
|
this.split_index = 1;
|
|
// NOTE: The order of these last two this.commands matters!
|
|
this.treeRoot = null;
|
|
this.ignoreInputs = true;
|
|
// maxDegreeButtonArray[this.max_degree].selected = true;
|
|
this.ignoreInputs = false;
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.enableUI = function(event)
|
|
{
|
|
var i;
|
|
for (i = 0; i < this.controls.length; i++)
|
|
{
|
|
this.controls[i].disabled = false;
|
|
}
|
|
for (i = 0; i < this.maxDegreeRadioButtons.length; i++)
|
|
{
|
|
this.maxDegreeRadioButtons[i].disabled = false;
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.disableUI = function(event)
|
|
{
|
|
for (var i = 0; i < this.controls.length; i++)
|
|
{
|
|
this.controls[i].disabled = true;
|
|
}
|
|
|
|
for (i = 0; i < this.maxDegreeRadioButtons.length; i++)
|
|
{
|
|
this.maxDegreeRadioButtons[i].disabled = true;
|
|
}
|
|
|
|
}
|
|
|
|
|
|
//TODO: Fix me!
|
|
BPlusTree.prototype.maxDegreeChangedHandler = function(newMaxDegree, event)
|
|
{
|
|
if (this.max_degree != newMaxDegree)
|
|
{
|
|
this.implementAction(this.changeDegree.bind(this), newMaxDegree);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
BPlusTree.prototype.insertCallback = function(event)
|
|
{
|
|
var insertedValue;
|
|
insertedValue = this.normalizeNumber(this.insertField.value, 4);
|
|
if (insertedValue != "")
|
|
{
|
|
this.insertField.value = "";
|
|
this.implementAction(this.insertElement.bind(this),insertedValue);
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.deleteCallback = function(event)
|
|
{
|
|
var deletedValue = this.deleteField.value;
|
|
if (deletedValue != "")
|
|
{
|
|
deletedValue = this.normalizeNumber(this.deleteField.value, 4);
|
|
this.deleteField.value = "";
|
|
this.implementAction(this.deleteElement.bind(this),deletedValue);
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.clearCallback = function(event)
|
|
{
|
|
this.implementAction(this.clearTree.bind(this), "");
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.premtiveSplitCallback = function(event)
|
|
{
|
|
// if (this.preemptiveSplit != this.premptiveSplitBox.checked)
|
|
// {
|
|
// this.implementAction(this.changePreemtiveSplit.bind(this), this.premptiveSplitBox.checked);
|
|
// }
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.changePreemtiveSplit = function(newValue)
|
|
{
|
|
// this.commands = new Array();
|
|
// this.cmd("Step");
|
|
// this.preemptiveSplit = newValue;
|
|
// if (this.premptiveSplitBox.checked != this.preemptiveSplit)
|
|
// {
|
|
// this.premptiveSplitBox.checked = this.preemptiveSplit;
|
|
// }
|
|
// return this.commands;
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.printCallback = function(event)
|
|
{
|
|
this.implementAction(this.printTree.bind(this),"");
|
|
}
|
|
|
|
|
|
|
|
BPlusTree.prototype.printTree = function(unused)
|
|
{
|
|
|
|
this.commands = new Array();
|
|
this.cmd("SetText", this.messageID, "Printing tree");
|
|
var firstLabel = this.nextIndex;
|
|
|
|
if (this.treeRoot != null)
|
|
{
|
|
this.xPosOfNextLabel = FIRST_PRINT_POS_X;
|
|
this.yPosOfNextLabel = this.first_print_pos_y;
|
|
|
|
var tmp = this.treeRoot;
|
|
|
|
this.cmd("SetHighlight", tmp.graphicID, 1);
|
|
this.cmd("Step");
|
|
while (!tmp.isLeaf)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tmp.graphicID, tmp.children[0].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tmp.graphicID, 0);
|
|
this.cmd("SetHighlight", tmp.children[0].graphicID, 1);
|
|
this.cmd("SetEdgeHighlight", tmp.graphicID, tmp.children[0].graphicID, 0);
|
|
this.cmd("Step");
|
|
tmp = tmp.children[0];
|
|
}
|
|
|
|
while (tmp!= null)
|
|
{
|
|
this.cmd("SetHighlight", tmp.graphicID, 1);
|
|
for (i = 0; i < tmp.numKeys; i++)
|
|
{
|
|
var nextLabelID = this.nextIndex++;
|
|
this.cmd("CreateLabel", nextLabelID, tmp.keys[i], this.getLabelX(tmp, i), tmp.y);
|
|
this.cmd("SetForegroundColor", nextLabelID, PRINT_COLOR);
|
|
this.cmd("Move", nextLabelID, this.xPosOfNextLabel, this.yPosOfNextLabel);
|
|
this.cmd("Step");
|
|
this.xPosOfNextLabel += PRINT_HORIZONTAL_GAP;
|
|
if (this.xPosOfNextLabel > PRINT_MAX)
|
|
{
|
|
this.xPosOfNextLabel = FIRST_PRINT_POS_X;
|
|
this.yPosOfNextLabel += PRINT_VERTICAL_GAP;
|
|
}
|
|
}
|
|
if (tmp.next != null)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tmp.graphicID, tmp.next.graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetEdgeHighlight", tmp.graphicID, tmp.next.graphicID, 0);
|
|
}
|
|
this.cmd("SetHighlight", tmp.graphicID, 0);
|
|
tmp = tmp.next;
|
|
}
|
|
this.cmd("Step");
|
|
for (var i = firstLabel; i < this.nextIndex; i++)
|
|
{
|
|
this.cmd("Delete", i);
|
|
}
|
|
this.nextIndex = firstLabel;
|
|
}
|
|
this.cmd("SetText", this.messageID, "");
|
|
return this.commands;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.clearTree = function(ignored)
|
|
{
|
|
this.commands = new Array();
|
|
this.deleteTree(this.treeRoot);
|
|
this.treeRoot = null;
|
|
this.nextIndex = 3;
|
|
return this.commands;
|
|
}
|
|
|
|
BPlusTree.prototype.deleteTree = function(tree)
|
|
{
|
|
if (tree != null)
|
|
{
|
|
if (!tree.isLeaf)
|
|
{
|
|
for (var i = 0; i <= tree.numKeys; i++)
|
|
{
|
|
this.cmd("Disconnect", tree.graphicID, tree.children[i].graphicID);
|
|
this.deleteTree(tree.children[i]);
|
|
tree.children[i] == null;
|
|
}
|
|
}
|
|
this.cmd("Delete", tree.graphicID);
|
|
}
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.changeDegree = function(degree)
|
|
{
|
|
this.commands = new Array();
|
|
this.deleteTree(this.treeRoot);
|
|
this.treeRoot = null;
|
|
this.nextIndex = 3;
|
|
var newDegree = degree;
|
|
this.ignoreInputs = true;
|
|
//TODO: Check me!
|
|
this.maxDegreeRadioButtons[newDegree - MIN_MAX_DEGREE].checked = true;
|
|
|
|
this.ignoreInputs = false;
|
|
this.max_degree = newDegree;
|
|
this.max_keys = newDegree - 1;
|
|
this.min_keys = Math.floor((newDegree + 1) / 2) - 1;
|
|
this.split_index = Math.floor((newDegree) / 2);
|
|
if (this.commands.length == 0)
|
|
{
|
|
this.cmd("Step");
|
|
}
|
|
if (newDegree % 2 != 0 && this.preemptiveSplit)
|
|
{
|
|
this.preemptiveSplit = false;
|
|
this.premptiveSplitBox.checked = false;
|
|
}
|
|
return this.commands;
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.findCallback = function(event)
|
|
{
|
|
var findValue;
|
|
findValue = this.normalizeNumber(this.findField.value, 4);
|
|
this.findField.value = "";
|
|
this.implementAction(this.findElement.bind(this),findValue);
|
|
}
|
|
|
|
BPlusTree.prototype.findElement = function(findValue)
|
|
{
|
|
this.commands = new Array();
|
|
|
|
this.cmd("SetText", this.messageID, "Finding " + findValue);
|
|
this.findInTree(this.treeRoot, findValue);
|
|
|
|
return this.commands;
|
|
}
|
|
|
|
|
|
|
|
BPlusTree.prototype.findInTree = function(tree, val)
|
|
{
|
|
if (tree != null)
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 1);
|
|
this.cmd("Step");
|
|
var i;
|
|
for (i = 0; i < tree.numKeys && tree.keys[i] < val; i++);
|
|
if (i == tree.numKeys)
|
|
{
|
|
if (!tree.isLeaf)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[tree.numKeys].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[tree.numKeys].graphicID, 0);
|
|
this.findInTree(tree.children[tree.numKeys], val);
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetText", this.messageID, "Element " + val + " is not in the tree");
|
|
}
|
|
}
|
|
else if (tree.keys[i] > val)
|
|
{
|
|
if (!tree.isLeaf)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i].graphicID, 0);
|
|
this.findInTree(tree.children[i], val);
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetText", this.messageID, "Element " + val + " is not in the tree");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("SetTextColor", tree.graphicID, "#FF0000", i);
|
|
this.cmd("SetText", this.messageID, "Element " + val + " found");
|
|
this.cmd("Step");
|
|
this.cmd("SetTextColor", tree.graphicID, FOREGROUND_COLOR, i);
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
|
|
this.cmd("Step");
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i+1].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i+1].graphicID, 0);
|
|
this.findInTree(tree.children[i+1], val);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetText", this.messageID, "Element " + val + " is not in the tree");
|
|
}
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.insertElement = function(insertedValue)
|
|
{
|
|
this.commands = new Array();
|
|
|
|
this.cmd("SetText", this.messageID, "Inserting " + insertedValue);
|
|
this.cmd("Step");
|
|
|
|
if (this.treeRoot == null)
|
|
{
|
|
this.treeRoot = new BTreeNode(this.nextIndex++, this.starting_x, STARTING_Y);
|
|
this.cmd("CreateBTreeNode",this.treeRoot.graphicID, WIDTH_PER_ELEM, NODE_HEIGHT, 1, this.starting_x, STARTING_Y, BACKGROUND_COLOR, FOREGROUND_COLOR);
|
|
this.treeRoot.keys[0] = insertedValue;
|
|
this.cmd("SetText", this.treeRoot.graphicID, insertedValue, 0);
|
|
}
|
|
else
|
|
{
|
|
this.insert(this.treeRoot, insertedValue);
|
|
if (!this.treeRoot.isLeaf)
|
|
{
|
|
this.resizeTree();
|
|
}
|
|
}
|
|
|
|
this.cmd("SetText", this.messageID, "");
|
|
|
|
return this.commands;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.insert = function(tree, insertValue)
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 1);
|
|
this.cmd("Step");
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("SetText", this.messageID, "Inserting " + insertValue + ". Inserting into a leaf");
|
|
tree.numKeys++;
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys);
|
|
var insertIndex = tree.numKeys - 1;
|
|
while (insertIndex > 0 && tree.keys[insertIndex - 1] > insertValue)
|
|
{
|
|
tree.keys[insertIndex] = tree.keys[insertIndex - 1];
|
|
this.cmd("SetText", tree.graphicID, tree.keys[insertIndex], insertIndex);
|
|
insertIndex--;
|
|
}
|
|
tree.keys[insertIndex] = insertValue;
|
|
this.cmd("SetText", tree.graphicID, tree.keys[insertIndex], insertIndex);
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
if (tree.next != null)
|
|
{
|
|
this.cmd("Disconnect", tree.graphicID, tree.next.graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
|
|
|
|
}
|
|
this.resizeTree();
|
|
this.insertRepair(tree);
|
|
}
|
|
else
|
|
{
|
|
var findIndex = 0;
|
|
while (findIndex < tree.numKeys && tree.keys[findIndex] < insertValue)
|
|
{
|
|
findIndex++;
|
|
}
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[findIndex].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[findIndex].graphicID, 0);
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.insert(tree.children[findIndex], insertValue);
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.insertRepair = function(tree)
|
|
{
|
|
if (tree.numKeys <= this.max_keys)
|
|
{
|
|
return;
|
|
}
|
|
else if (tree.parent == null)
|
|
{
|
|
this.treeRoot = this.split(tree);
|
|
return;
|
|
}
|
|
else
|
|
{
|
|
var newNode = this.split(tree);
|
|
this.insertRepair(newNode);
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.split = function(tree)
|
|
{
|
|
this.cmd("SetText", this.messageID, "Node now contains too many keys. Splittig ...");
|
|
this.cmd("SetHighlight", tree.graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
var rightNode = new BTreeNode(this.nextIndex++, tree.x + 100, tree.y);
|
|
|
|
var risingNode = tree.keys[this.split_index];
|
|
|
|
var i;
|
|
var parentIndex
|
|
if (tree.parent != null)
|
|
{
|
|
var currentParent = tree.parent;
|
|
for (parentIndex = 0; parentIndex < currentParent.numKeys + 1 && currentParent.children[parentIndex] != tree; parentIndex++);
|
|
if (parentIndex == currentParent.numKeys + 1)
|
|
{
|
|
throw new Error("Couldn't find which child we were!");
|
|
}
|
|
this.cmd("SetNumElements", currentParent.graphicID, currentParent.numKeys + 1);
|
|
for (i = currentParent.numKeys; i > parentIndex; i--)
|
|
{
|
|
currentParent.children[i+1] = currentParent.children[i];
|
|
this.cmd("Disconnect", currentParent.graphicID, currentParent.children[i].graphicID);
|
|
this.cmd("Connect", currentParent.graphicID, currentParent.children[i].graphicID, FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
i+1);
|
|
|
|
currentParent.keys[i] = currentParent.keys[i-1];
|
|
this.cmd("SetText", currentParent.graphicID, currentParent.keys[i] ,i);
|
|
}
|
|
currentParent.numKeys++;
|
|
currentParent.keys[parentIndex] = risingNode;
|
|
this.cmd("SetText", currentParent.graphicID, "", parentIndex);
|
|
this.cmd("CreateLabel", this.moveLabel1ID, risingNode, this.getLabelX(tree, this.split_index), tree.y)
|
|
this.cmd("Move", this.moveLabel1ID, this.getLabelX(currentParent, parentIndex), currentParent.y)
|
|
|
|
|
|
|
|
|
|
currentParent.children[parentIndex+1] = rightNode;
|
|
rightNode.parent = currentParent;
|
|
|
|
}
|
|
|
|
var rightSplit;
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
rightSplit = this.split_index;
|
|
rightNode.next = tree.next;
|
|
tree.next = rightNode;
|
|
}
|
|
else
|
|
{
|
|
rightSplit = this.split_index + 1;
|
|
}
|
|
|
|
rightNode.numKeys = tree.numKeys - rightSplit;
|
|
|
|
this.cmd("CreateBTreeNode",rightNode.graphicID, WIDTH_PER_ELEM, NODE_HEIGHT, tree.numKeys -rightSplit, tree.x, tree.y, BACKGROUND_COLOR, FOREGROUND_COLOR);
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
if (rightNode.next != null)
|
|
{
|
|
|
|
this.cmd("Disconnect", tree.graphicID, rightNode.next.graphicID);
|
|
this.cmd("Connect", rightNode.graphicID,
|
|
rightNode.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
rightNode.numKeys);
|
|
|
|
|
|
}
|
|
this.cmd("Connect", tree.graphicID,
|
|
rightNode.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
this.split_index);
|
|
}
|
|
|
|
|
|
for (var i = rightSplit; i < tree.numKeys + 1; i++)
|
|
{
|
|
rightNode.children[i - rightSplit] = tree.children[i];
|
|
if (tree.children[i] != null)
|
|
{
|
|
rightNode.isLeaf = false;
|
|
this.cmd("Disconnect", tree.graphicID, tree.children[i].graphicID);
|
|
|
|
this.cmd("Connect", rightNode.graphicID,
|
|
rightNode.children[i - rightSplit].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
i - rightSplit);
|
|
if (tree.children[i] != null)
|
|
{
|
|
tree.children[i].parent = rightNode;
|
|
}
|
|
tree.children[i] = null;
|
|
|
|
}
|
|
}
|
|
for (i =rightSplit; i < tree.numKeys; i++)
|
|
{
|
|
rightNode.keys[i - rightSplit] = tree.keys[i];
|
|
this.cmd("SetText", rightNode.graphicID, rightNode.keys[i -rightSplit], i - rightSplit);
|
|
}
|
|
var leftNode = tree;
|
|
leftNode.numKeys = this.split_index;
|
|
// TO MAKE UNDO WORK -- CAN REMOVE LATER VV
|
|
for (i = this.split_index; i < tree.numKeys; i++)
|
|
{
|
|
this.cmd("SetText", tree.graphicID, "", i);
|
|
}
|
|
// TO MAKE UNDO WORK -- CAN REMOVE LATER ^^
|
|
this.cmd("SetNumElements", tree.graphicID, this.split_index);
|
|
|
|
if (tree.parent != null)
|
|
{
|
|
this.cmd("Connect", currentParent.graphicID, rightNode.graphicID, FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
parentIndex + 1);
|
|
this.resizeTree();
|
|
this.cmd("Step")
|
|
this.cmd("Delete", this.moveLabel1ID);
|
|
this.cmd("SetText", currentParent.graphicID, risingNode, parentIndex);
|
|
return tree.parent;
|
|
}
|
|
else // if (tree.parent == null)
|
|
{
|
|
this.treeRoot = new BTreeNode(this.nextIndex++, this.starting_x, STARTING_Y);
|
|
this.cmd("CreateBTreeNode",this.treeRoot.graphicID, WIDTH_PER_ELEM, NODE_HEIGHT, 1, this.starting_x, STARTING_Y,BACKGROUND_COLOR, FOREGROUND_COLOR);
|
|
this.treeRoot.keys[0] = risingNode;
|
|
this.cmd("SetText", this.treeRoot.graphicID, risingNode, 0);
|
|
this.treeRoot.children[0] = leftNode;
|
|
this.treeRoot.children[1] = rightNode;
|
|
leftNode.parent = this.treeRoot;
|
|
rightNode.parent = this.treeRoot;
|
|
this.cmd("Connect", this.treeRoot.graphicID, leftNode.graphicID, FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
0); // Connection Point
|
|
this.cmd("Connect", this.treeRoot.graphicID, rightNode.graphicID, FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
1); // Connection Point
|
|
this.treeRoot.isLeaf = false;
|
|
return this.treeRoot;
|
|
}
|
|
|
|
|
|
|
|
}
|
|
|
|
BPlusTree.prototype.deleteElement = function(deletedValue)
|
|
{
|
|
this.commands = new Array();
|
|
this.cmd("SetText", 0, "正在刪除 "+deletedValue);
|
|
this.cmd("Step");
|
|
this.cmd("SetText", 0, "");
|
|
this.cmd("SetText", 0, "");
|
|
this.doDelete(this.treeRoot, deletedValue);
|
|
if (this.treeRoot.numKeys == 0)
|
|
{
|
|
this.cmd("Delete", this.treeRoot.graphicID);
|
|
this.treeRoot = this.treeRoot.children[0];
|
|
this.treeRoot.parent = null;
|
|
this.resizeTree();
|
|
}
|
|
return this.commands;
|
|
}
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.doDelete = function(tree, val)
|
|
{
|
|
if (tree != null)
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 1);
|
|
this.cmd("Step");
|
|
var i;
|
|
for (i = 0; i < tree.numKeys && tree.keys[i] < val; i++);
|
|
if (i == tree.numKeys)
|
|
{
|
|
if (!tree.isLeaf)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[tree.numKeys].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[tree.numKeys].graphicID, 0);
|
|
this.doDelete(tree.children[tree.numKeys], val);
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
}
|
|
}
|
|
else if (!tree.isLeaf && tree.keys[i] == val)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i+1].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i+1].graphicID, 0);
|
|
this.doDelete(tree.children[i+1], val);
|
|
}
|
|
else if (!tree.isLeaf)
|
|
{
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i].graphicID, 1);
|
|
this.cmd("Step");
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetEdgeHighlight", tree.graphicID, tree.children[i].graphicID, 0);
|
|
this.doDelete(tree.children[i], val);
|
|
}
|
|
else if (tree.isLeaf && tree.keys[i] == val)
|
|
{
|
|
this.cmd("SetTextColor", tree.graphicID, 0xFF0000, i);
|
|
this.cmd("Step");
|
|
this.cmd("SetTextColor", tree.graphicID, FOREGROUND_COLOR, i);
|
|
for (var j = i; j < tree.numKeys - 1; j++)
|
|
{
|
|
tree.keys[j] = tree.keys[j+1];
|
|
this.cmd("SetText", tree.graphicID, tree.keys[j], j);
|
|
}
|
|
tree.numKeys--;
|
|
this.cmd("SetText", tree.graphicID, "", tree.numKeys);
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys);
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
|
|
if (tree.next != null)
|
|
{
|
|
this.cmd("Disconnect", tree.graphicID, tree.next.graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
}
|
|
|
|
// Bit of a hack -- if we remove the smallest element in a leaf, then find the *next* smallest element
|
|
// (somewhat tricky if the leaf is now empty!), go up our parent stack, and fix index keys
|
|
if (i == 0 && tree.parent != null)
|
|
{
|
|
var nextSmallest = "";
|
|
var parentNode = tree.parent;
|
|
var parentIndex;
|
|
for (parentIndex = 0; parentNode.children[parentIndex] != tree; parentIndex++);
|
|
if (tree.numKeys == 0)
|
|
{
|
|
if (parentIndex == parentNode.numKeys)
|
|
{
|
|
nextSmallest == "";
|
|
}
|
|
else
|
|
{
|
|
nextSmallest = parentNode.children[parentIndex+1].keys[0];
|
|
}
|
|
}
|
|
else
|
|
{
|
|
nextSmallest = tree.keys[0];
|
|
}
|
|
while (parentNode != null)
|
|
{
|
|
if (parentIndex > 0 && parentNode.keys[parentIndex - 1] == val)
|
|
{
|
|
parentNode.keys[parentIndex - 1] = nextSmallest;
|
|
this.cmd("SetText", parentNode.graphicID, parentNode.keys[parentIndex - 1], parentIndex - 1);
|
|
}
|
|
var grandParent = parentNode.parent;
|
|
for (parentIndex = 0; grandParent != null && grandParent.children[parentIndex] != parentNode; parentIndex++);
|
|
parentNode = grandParent;
|
|
|
|
}
|
|
|
|
}
|
|
this.repairAfterDelete(tree);
|
|
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
BPlusTree.prototype.mergeRight = function(tree)
|
|
{
|
|
this.cmd("SetText", this.messageID, "Merging node");
|
|
|
|
var parentNode = tree.parent;
|
|
var parentIndex = 0;
|
|
for (parentIndex = 0; parentNode.children[parentIndex] != tree; parentIndex++);
|
|
var rightSib = parentNode.children[parentIndex+1];
|
|
this.cmd("SetHighlight", tree.graphicID, 1);
|
|
this.cmd("SetHighlight", parentNode.graphicID, 1);
|
|
this.cmd("SetHighlight", rightSib.graphicID, 1);
|
|
|
|
this.cmd("Step");
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys + rightSib.numKeys);
|
|
}
|
|
else
|
|
{
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys + rightSib.numKeys + 1);
|
|
this.cmd("SetText", tree.graphicID, "", tree.numKeys);
|
|
this.cmd("CreateLabel", this.moveLabel1ID, parentNode.keys[parentIndex], this.getLabelX(parentNode, parentIndex), parentNode.y);
|
|
tree.keys[tree.numKeys] = parentNode.keys[parentIndex];
|
|
}
|
|
tree.x = (tree.x + rightSib.x) / 2
|
|
this.cmd("SetPosition", tree.graphicID, tree.x, tree.y);
|
|
|
|
|
|
var fromParentIndex = tree.numKeys;
|
|
|
|
|
|
for (var i = 0; i < rightSib.numKeys; i++)
|
|
{
|
|
var insertIndex = tree.numKeys + 1 + i;
|
|
if (tree.isLeaf)
|
|
{
|
|
insertIndex -= 1;
|
|
}
|
|
tree.keys[insertIndex] = rightSib.keys[i];
|
|
this.cmd("SetText", tree.graphicID, tree.keys[insertIndex], insertIndex);
|
|
this.cmd("SetText", rightSib.graphicID, "", i);
|
|
}
|
|
if (!tree.isLeaf)
|
|
{
|
|
for (i = 0; i <= rightSib.numKeys; i++)
|
|
{
|
|
this.cmd("Disconnect", rightSib.graphicID, rightSib.children[i].graphicID);
|
|
tree.children[tree.numKeys + 1 + i] = rightSib.children[i];
|
|
tree.children[tree.numKeys + 1 + i].parent = tree;
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.children[tree.numKeys + 1 + i].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
tree.numKeys + 1 + i);
|
|
}
|
|
tree.numKeys = tree.numKeys + rightSib.numKeys + 1;
|
|
|
|
}
|
|
else
|
|
{
|
|
tree.numKeys = tree.numKeys + rightSib.numKeys;
|
|
|
|
tree.next = rightSib.next;
|
|
if (rightSib.next != null)
|
|
{
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
|
|
}
|
|
}
|
|
this.cmd("Disconnect", parentNode.graphicID, rightSib.graphicID);
|
|
for (i = parentIndex+1; i < parentNode.numKeys; i++)
|
|
{
|
|
this.cmd("Disconnect", parentNode.graphicID, parentNode.children[i+1].graphicID);
|
|
parentNode.children[i] = parentNode.children[i+1];
|
|
this.cmd("Connect", parentNode.graphicID,
|
|
parentNode.children[i].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
i);
|
|
parentNode.keys[i-1] = parentNode.keys[i];
|
|
this.cmd("SetText", parentNode.graphicID, parentNode.keys[i-1], i-1);
|
|
}
|
|
this.cmd("SetText", parentNode.graphicID, "", parentNode.numKeys - 1);
|
|
parentNode.numKeys--;
|
|
this.cmd("SetNumElements", parentNode.graphicID, parentNode.numKeys);
|
|
this.cmd("SetHighlight", tree.graphicID, 0);
|
|
this.cmd("SetHighlight", parentNode.graphicID, 0);
|
|
this.cmd("SetHighlight", rightSib.graphicID, 0);
|
|
|
|
this.cmd("Delete", rightSib.graphicID);
|
|
if (!tree.isLeaf)
|
|
{
|
|
this.cmd("Move", this.moveLabel1ID, this.getLabelX(tree, fromParentIndex), tree.y);
|
|
this.cmd("Step");
|
|
this.cmd("Delete", this.moveLabel1ID);
|
|
this.cmd("SetText", tree.graphicID, tree.keys[fromParentIndex], fromParentIndex);
|
|
}
|
|
// this.resizeTree();
|
|
|
|
this.cmd("SetText", this.messageID, "");
|
|
return tree;
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.stealFromRight = function(tree, parentIndex)
|
|
{
|
|
// Steal from right sibling
|
|
var parentNode = tree.parent;
|
|
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys+1);
|
|
|
|
this.cmd("SetText", this.messageID, "Stealing from right sibling");
|
|
|
|
var rightSib = parentNode.children[parentIndex + 1];
|
|
tree.numKeys++;
|
|
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys);
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("Disconnect", tree.graphicID, tree.next.graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
}
|
|
|
|
|
|
this.cmd("SetText", tree.graphicID, "", tree.numKeys - 1);
|
|
this.cmd("SetText", parentNode.graphicID, "", parentIndex);
|
|
this.cmd("SetText", rightSib.graphicID, "", 0);
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("CreateLabel", this.moveLabel1ID, rightSib.keys[1], this.getLabelX(rightSib, 1), rightSib.y)
|
|
this.cmd("CreateLabel", this.moveLabel2ID, rightSib.keys[0], this.getLabelX(rightSib, 0), rightSib.y)
|
|
tree.keys[tree.numKeys - 1] = rightSib.keys[0];
|
|
parentNode.keys[parentIndex] = rightSib.keys[1];
|
|
|
|
}
|
|
else
|
|
{
|
|
this.cmd("CreateLabel", this.moveLabel1ID, rightSib.keys[0], this.getLabelX(rightSib, 0), rightSib.y)
|
|
this.cmd("CreateLabel", this.moveLabel2ID, parentNode.keys[parentIndex], this.getLabelX(parentNode, parentIndex), parentNode.y)
|
|
tree.keys[tree.numKeys - 1] = parentNode.keys[parentIndex];
|
|
parentNode.keys[parentIndex] = rightSib.keys[0];
|
|
}
|
|
|
|
|
|
this.cmd("Move", this.moveLabel1ID, this.getLabelX(parentNode, parentIndex), parentNode.y);
|
|
this.cmd("Move", this.moveLabel2ID, this.getLabelX(tree, tree.numKeys - 1), tree.y);
|
|
|
|
this.cmd("Step")
|
|
this.cmd("Delete", this.moveLabel1ID);
|
|
this.cmd("Delete", this.moveLabel2ID);
|
|
|
|
|
|
|
|
|
|
this.cmd("SetText", tree.graphicID, tree.keys[tree.numKeys - 1], tree.numKeys - 1);
|
|
this.cmd("SetText", parentNode.graphicID, parentNode.keys[parentIndex], parentIndex);
|
|
if (!tree.isLeaf)
|
|
{
|
|
tree.children[tree.numKeys] = rightSib.children[0];
|
|
tree.children[tree.numKeys].parent = tree;
|
|
this.cmd("Disconnect", rightSib.graphicID, rightSib.children[0].graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.children[tree.numKeys].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
// TODO::CHECKME!
|
|
|
|
for (var i = 1; i < rightSib.numKeys + 1; i++)
|
|
{
|
|
this.cmd("Disconnect", rightSib.graphicID, rightSib.children[i].graphicID);
|
|
rightSib.children[i-1] = rightSib.children[i];
|
|
this.cmd("Connect", rightSib.graphicID,
|
|
rightSib.children[i-1].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
i-1);
|
|
}
|
|
|
|
}
|
|
for (i = 1; i < rightSib.numKeys; i++)
|
|
{
|
|
rightSib.keys[i-1] = rightSib.keys[i];
|
|
this.cmd("SetText", rightSib.graphicID, rightSib.keys[i-1], i-1);
|
|
}
|
|
this.cmd("SetText", rightSib.graphicID, "", rightSib.numKeys-1);
|
|
rightSib.numKeys--;
|
|
this.cmd("SetNumElements", rightSib.graphicID, rightSib.numKeys);
|
|
this.resizeTree();
|
|
this.cmd("SetText", this.messageID, "");
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
|
|
if (rightSib.next != null)
|
|
{
|
|
this.cmd("Disconnect", rightSib.graphicID, rightSib.next.graphicID);
|
|
this.cmd("Connect", rightSib.graphicID,
|
|
rightSib.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
rightSib.numKeys);
|
|
}
|
|
|
|
}
|
|
return tree;
|
|
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.stealFromLeft = function(tree, parentIndex)
|
|
{
|
|
var parentNode = tree.parent;
|
|
// Steal from left sibling
|
|
tree.numKeys++;
|
|
this.cmd("SetNumElements", tree.graphicID, tree.numKeys);
|
|
|
|
if (tree.isLeaf && tree.next != null)
|
|
{
|
|
|
|
this.cmd("Disconnect", tree.graphicID, tree.next.graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.next.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
tree.numKeys);
|
|
}
|
|
|
|
|
|
this.cmd("SetText", this.messageID, "Node has too few keys. Stealing from left sibling.");
|
|
|
|
for (i = tree.numKeys - 1; i > 0; i--)
|
|
{
|
|
tree.keys[i] = tree.keys[i-1];
|
|
this.cmd("SetText", tree.graphicID, tree.keys[i], i);
|
|
}
|
|
var leftSib = parentNode.children[parentIndex -1];
|
|
|
|
this.cmd("SetText", tree.graphicID, "", 0);
|
|
this.cmd("SetText", parentNode.graphicID, "", parentIndex - 1);
|
|
this.cmd("SetText", leftSib.graphicID, "", leftSib.numKeys - 1);
|
|
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("CreateLabel", this.moveLabel1ID, leftSib.keys[leftSib.numKeys - 1], this.getLabelX(leftSib, leftSib.numKeys - 1), leftSib.y)
|
|
this.cmd("CreateLabel", this.moveLabel2ID,leftSib.keys[leftSib.numKeys - 1], this.getLabelX(leftSib, leftSib.numKeys - 1), leftSib.y)
|
|
tree.keys[0] = leftSib.keys[leftSib.numKeys - 1];
|
|
parentNode.keys[parentIndex-1] = leftSib.keys[leftSib.numKeys - 1];
|
|
}
|
|
else
|
|
{
|
|
this.cmd("CreateLabel", this.moveLabel1ID, leftSib.keys[leftSib.numKeys - 1], this.getLabelX(leftSib, leftSib.numKeys - 1), leftSib.y)
|
|
this.cmd("CreateLabel", this.moveLabel2ID, parentNode.keys[parentIndex - 1], this.getLabelX(parentNode, parentIndex - 1), parentNode.y)
|
|
tree.keys[0] = parentNode.keys[parentIndex - 1];
|
|
parentNode.keys[parentIndex-1] = leftSib.keys[leftSib.numKeys - 1];
|
|
}
|
|
this.cmd("Move", this.moveLabel1ID, this.getLabelX(parentNode, parentIndex - 1), parentNode.y);
|
|
this.cmd("Move", this.moveLabel2ID, this.getLabelX(tree, 0), tree.y);
|
|
|
|
this.cmd("Step")
|
|
this.cmd("Delete", this.moveLabel1ID);
|
|
this.cmd("Delete", this.moveLabel2ID);
|
|
|
|
|
|
if (!tree.isLeaf)
|
|
{
|
|
for (var i = tree.numKeys; i > 0; i--)
|
|
{
|
|
this.cmd("Disconnect", tree.graphicID, tree.children[i-1].graphicID);
|
|
tree.children[i] =tree.children[i-1];
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.children[i].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
i);
|
|
}
|
|
tree.children[0] = leftSib.children[leftSib.numKeys];
|
|
this.cmd("Disconnect", leftSib.graphicID, leftSib.children[leftSib.numKeys].graphicID);
|
|
this.cmd("Connect", tree.graphicID,
|
|
tree.children[0].graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
0, // Directed
|
|
"", // Label
|
|
0);
|
|
leftSib.children[leftSib.numKeys] = null;
|
|
tree.children[0].parent = tree;
|
|
|
|
}
|
|
|
|
this.cmd("SetText", tree.graphicID, tree.keys[0], 0);
|
|
this.cmd("SetText", parentNode.graphicID, parentNode.keys[parentIndex - 1], parentIndex - 1);
|
|
this.cmd("SetText", leftSib.graphicID,"", leftSib.numKeys - 1);
|
|
|
|
leftSib.numKeys--;
|
|
this.cmd("SetNumElements", leftSib.graphicID, leftSib.numKeys);
|
|
this.resizeTree();
|
|
this.cmd("SetText", this.messageID, "");
|
|
|
|
|
|
if (tree.isLeaf)
|
|
{
|
|
this.cmd("Disconnect", leftSib.graphicID, tree.graphicID);
|
|
this.cmd("Connect", leftSib.graphicID,
|
|
tree.graphicID,
|
|
FOREGROUND_COLOR,
|
|
0, // Curve
|
|
1, // Directed
|
|
"", // Label
|
|
leftSib.numKeys);
|
|
|
|
}
|
|
|
|
|
|
return tree;
|
|
}
|
|
|
|
|
|
BPlusTree.prototype.repairAfterDelete = function(tree)
|
|
{
|
|
if (tree.numKeys < this.min_keys)
|
|
{
|
|
if (tree.parent == null)
|
|
{
|
|
if (tree.numKeys == 0)
|
|
{
|
|
this.cmd("Delete", tree.graphicID);
|
|
this.treeRoot = tree.children[0];
|
|
if (this.treeRoot != null)
|
|
this.treeRoot.parent = null;
|
|
this.resizeTree();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
var parentNode = tree.parent;
|
|
for (var parentIndex = 0; parentNode.children[parentIndex] != tree; parentIndex++);
|
|
|
|
|
|
if (parentIndex > 0 && parentNode.children[parentIndex - 1].numKeys > this.min_keys)
|
|
{
|
|
this.stealFromLeft(tree, parentIndex);
|
|
|
|
}
|
|
else if (parentIndex < parentNode.numKeys && parentNode.children[parentIndex + 1].numKeys > this.min_keys)
|
|
{
|
|
this.stealFromRight(tree,parentIndex);
|
|
|
|
}
|
|
else if (parentIndex == 0)
|
|
{
|
|
// Merge with right sibling
|
|
var nextNode = this.mergeRight(tree);
|
|
this.repairAfterDelete(nextNode.parent);
|
|
}
|
|
else
|
|
{
|
|
// Merge with left sibling
|
|
nextNode = this.mergeRight(parentNode.children[parentIndex-1]);
|
|
this.repairAfterDelete(nextNode.parent);
|
|
|
|
}
|
|
|
|
|
|
}
|
|
}
|
|
else if (tree.parent != null)
|
|
{
|
|
|
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
BPlusTree.prototype.getLabelX = function(tree, index)
|
|
{
|
|
return tree.x - WIDTH_PER_ELEM * tree.numKeys / 2 + WIDTH_PER_ELEM / 2 + index * WIDTH_PER_ELEM;
|
|
}
|
|
|
|
BPlusTree.prototype.resizeTree = function()
|
|
{
|
|
this.resizeWidths(this.treeRoot);
|
|
this.setNewPositions(this.treeRoot, this.starting_x, STARTING_Y);
|
|
this.animateNewPositions(this.treeRoot);
|
|
}
|
|
|
|
BPlusTree.prototype.setNewPositions = function(tree, xPosition, yPosition)
|
|
{
|
|
if (tree != null)
|
|
{
|
|
tree.y = yPosition;
|
|
tree.x = xPosition;
|
|
if (!tree.isLeaf)
|
|
{
|
|
var leftEdge = xPosition - tree.width / 2;
|
|
var priorWidth = 0;
|
|
for (var i = 0; i < tree.numKeys+1; i++)
|
|
{
|
|
this.setNewPositions(tree.children[i], leftEdge + priorWidth + tree.widths[i] / 2, yPosition+HEIGHT_DELTA);
|
|
priorWidth += tree.widths[i];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
BPlusTree.prototype.animateNewPositions = function(tree)
|
|
{
|
|
if (tree == null)
|
|
{
|
|
return;
|
|
}
|
|
var i;
|
|
for (i = 0; i < tree.numKeys + 1; i++)
|
|
{
|
|
this.animateNewPositions(tree.children[i]);
|
|
}
|
|
this.cmd("Move", tree.graphicID, tree.x, tree.y);
|
|
}
|
|
|
|
BPlusTree.prototype.resizeWidths = function(tree)
|
|
{
|
|
if (tree == null)
|
|
{
|
|
return 0;
|
|
}
|
|
if (tree.isLeaf)
|
|
{
|
|
for (var i = 0; i < tree.numKeys + 1; i++)
|
|
{
|
|
tree.widths[i] = 0;
|
|
}
|
|
tree.width = tree.numKeys * WIDTH_PER_ELEM + NODE_SPACING;
|
|
return tree.width;
|
|
}
|
|
else
|
|
{
|
|
var treeWidth = 0;
|
|
for (i = 0; i < tree.numKeys+1; i++)
|
|
{
|
|
tree.widths[i] = this.resizeWidths(tree.children[i]);
|
|
treeWidth = treeWidth + tree.widths[i];
|
|
}
|
|
treeWidth = Math.max(treeWidth, tree.numKeys * WIDTH_PER_ELEM + NODE_SPACING);
|
|
tree.width = treeWidth;
|
|
return treeWidth;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
function BTreeNode(id, initialX, initialY)
|
|
{
|
|
this.widths = [];
|
|
this.keys = [];
|
|
this.children = [];
|
|
this.x = initialX;
|
|
this.y = initialY;
|
|
this.graphicID = id;
|
|
this.numKeys = 1;
|
|
this.isLeaf = true;
|
|
this.parent = null;
|
|
|
|
this.leftWidth = 0;
|
|
this.rightWidth = 0;
|
|
// Could use children for next pointer, but I got lazy ...
|
|
this.next = null;
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
var currentAlg;
|
|
|
|
function init()
|
|
{
|
|
var animManag = initCanvas();
|
|
currentAlg = new BPlusTree(animManag, canvas.width, canvas.height);
|
|
}
|