/* Copyright (c) 1995-2000, The Hypersonic SQL Group.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of the Hypersonic SQL Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE HYPERSONIC SQL GROUP,
* 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.
*
* This software consists of voluntary contributions made by many individuals
* on behalf of the Hypersonic SQL Group.
*
*
* For work added by the HSQL Development Group:
*
* Copyright (c) 2001-2009, The HSQL Development Group
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of the HSQL Development Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
* 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.
*/
package org.hsqldb.index;
import java.io.IOException;
import org.hsqldb.Error;
import org.hsqldb.ErrorCode;
import org.hsqldb.RowAVLDisk;
import org.hsqldb.Row;
import org.hsqldb.lib.IntLookup;
import org.hsqldb.persist.PersistentStore;
import org.hsqldb.rowio.RowInputInterface;
import org.hsqldb.rowio.RowOutputInterface;
import org.hsqldb.RowAVL;
// fredt@users 20020221 - patch 513005 by sqlbob@users (RMP)
// fredt@users 20020920 - path 1.7.1 - refactoring to cut mamory footprint
// fredt@users 20021205 - path 1.7.2 - enhancements
/**
* Cached table Node implementation.<p>
* Only integral references to left, right and parent nodes in the AVL tree
* are held and used as pointers data.<p>
*
* iId is a reference to the Index object that contains this node.<br>
* This fields can be eliminated in the future, by changing the
* method signatures to take a Index parameter from Index.java (fredt@users)
*
* New class derived from Hypersonic SQL code and enhanced in HSQLDB. <p>
*
* @author Thomas Mueller (Hypersonic SQL Group)
* @version 1.9.0
* @since Hypersonic SQL
*/
public class NodeAVLDisk extends NodeAVL {
final RowAVLDisk row;
//
protected NodeAVLDisk nLeft;
protected NodeAVLDisk nRight;
protected NodeAVLDisk nParent;
//
public int iData;
private int iLeft = NO_POS;
private int iRight = NO_POS;
private int iParent = NO_POS;
private int iId; // id of Index object for this Node
public static final int SIZE_IN_BYTE = 4 * 4;
public NodeAVLDisk(RowAVLDisk r, RowInputInterface in,
int id) throws IOException {
row = r;
iId = id;
iData = r.getPos();
iBalance = in.readInt();
iLeft = in.readInt();
if (iLeft <= 0) {
iLeft = NO_POS;
}
iRight = in.readInt();
if (iRight <= 0) {
iRight = NO_POS;
}
iParent = in.readInt();
if (iParent <= 0) {
iParent = NO_POS;
}
}
public NodeAVLDisk(RowAVLDisk r, int id) {
row = r;
iId = id;
iData = r.getPos();
}
public void delete() {
iLeft = NO_POS;
iRight = NO_POS;
iParent = NO_POS;
iBalance = -2;
}
public boolean isInMemory() {
return row.isInMemory();
}
public boolean isMemory() {
return false;
}
public int getPos() {
return iData;
}
Row getRow(PersistentStore store) {
if (!row.isInMemory()) {
return (RowAVLDisk) store.get(this.row, false);
} else {
row.updateAccessCount(store.getAccessCount());
}
return row;
}
private NodeAVLDisk findNode(PersistentStore store, int pos) {
NodeAVLDisk ret = null;
RowAVLDisk r = (RowAVLDisk) store.get(pos, false);
if (r != null) {
ret = (NodeAVLDisk) r.getNode(iId);
}
return ret;
}
boolean isLeft(NodeAVL n) {
if (n == null) {
return iLeft == NO_POS;
}
return iLeft == ((NodeAVLDisk) n).getPos();
}
boolean isRight(NodeAVL n) {
if (n == null) {
return iRight == NO_POS;
}
return iRight == ((NodeAVLDisk) n).getPos();
}
NodeAVL getLeft(PersistentStore store) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.isInMemory()) {
row = (RowAVLDisk) store.get(this.row, false);
node = (NodeAVLDisk) row.getNode(iId);
}
if (node.iLeft == NO_POS) {
return null;
}
if (node.nLeft == null || !node.nLeft.isInMemory()) {
node.nLeft = findNode(store, node.iLeft);
node.nLeft.nParent = node;
}
return node.nLeft;
}
NodeAVL getRight(PersistentStore store) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.isInMemory()) {
row = (RowAVLDisk) store.get(this.row, false);
node = (NodeAVLDisk) row.getNode(iId);
}
if (node.iRight == NO_POS) {
return null;
}
if (node.nRight == null || !node.nRight.isInMemory()) {
node.nRight = findNode(store, node.iRight);
node.nRight.nParent = node;
}
return node.nRight;
}
NodeAVL getParent(PersistentStore store) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.isInMemory()) {
row = (RowAVLDisk) store.get(this.row, false);
node = (NodeAVLDisk) row.getNode(iId);
}
if (node.iParent == NO_POS) {
return null;
}
if (node.nParent == null || !node.nParent.isInMemory()) {
node.nParent = findNode(store, iParent);
}
return node.nParent;
}
int getBalance() {
return iBalance;
}
boolean isRoot() {
return iParent == NodeAVL.NO_POS;
}
boolean isFromLeft(PersistentStore store) {
if (this.isRoot()) {
return true;
}
NodeAVLDisk parent = (NodeAVLDisk) getParent(store);
return getPos() == parent.iLeft;
}
NodeAVL setParent(PersistentStore store, NodeAVL n) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.keepInMemory(true)) {
row = (RowAVLDisk) store.get(this.row, true);
node = (NodeAVLDisk) row.getNode(iId);
}
if (!row.isInMemory()) {
throw Error.runtimeError(ErrorCode.U_S0500, "NAVLD");
}
row.setNodesChanged();
node.iParent = n == null ? NO_POS
: n.getPos();
if (n != null && !n.isInMemory()) {
n = findNode(store, n.getPos());
}
node.nParent = (NodeAVLDisk) n;
row.keepInMemory(false);
return node;
}
public NodeAVL setBalance(PersistentStore store, int b) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.keepInMemory(true)) {
row = (RowAVLDisk) store.get(this.row, true);
node = (NodeAVLDisk) row.getNode(iId);
}
if (!row.isInMemory()) {
throw Error.runtimeError(ErrorCode.U_S0500, "NAVLD");
}
row.setNodesChanged();
node.iBalance = b;
row.keepInMemory(false);
return node;
}
NodeAVL setLeft(PersistentStore store, NodeAVL n) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.keepInMemory(true)) {
row = (RowAVLDisk) store.get(this.row, true);
node = (NodeAVLDisk) row.getNode(iId);
}
if (!row.isInMemory()) {
throw Error.runtimeError(ErrorCode.U_S0500, "NAVLD");
}
row.setNodesChanged();
node.iLeft = n == null ? NO_POS
: n.getPos();
if (n != null && !n.isInMemory()) {
n = findNode(store, n.getPos());
}
node.nLeft = (NodeAVLDisk) n;
row.keepInMemory(false);
return node;
}
NodeAVL setRight(PersistentStore store, NodeAVL n) {
NodeAVLDisk node = this;
RowAVLDisk row = this.row;
if (!row.keepInMemory(true)) {
row = (RowAVLDisk) store.get(this.row, true);
node = (NodeAVLDisk) row.getNode(iId);
}
if (!row.isInMemory()) {
throw Error.runtimeError(ErrorCode.U_S0500, "NAVLD");
}
row.setNodesChanged();
node.iRight = n == null ? NO_POS
: n.getPos();
if (n != null && !n.isInMemory()) {
n = findNode(store, n.getPos());
}
node.nRight = (NodeAVLDisk) n;
row.keepInMemory(false);
return node;
}
boolean equals(NodeAVL n) {
return this == n
|| (n != null && getPos() == ((NodeAVLDisk) n).getPos());
}
public int getRealSize(RowOutputInterface out) {
return NodeAVLDisk.SIZE_IN_BYTE;
}
public void setInMemory(boolean in) {
if (!in) {
if (nLeft != null) {
nLeft.nParent = null;
}
if (nRight != null) {
nRight.nParent = null;
}
if (nParent != null) {
if (iData == nParent.iLeft) {
nParent.nLeft = null;
} else {
nParent.nRight = null;
}
}
nLeft = nRight = nParent = null;
}
}
public void write(RowOutputInterface out) {
out.writeInt(iBalance);
out.writeInt((iLeft == NO_POS) ? 0
: iLeft);
out.writeInt((iRight == NO_POS) ? 0
: iRight);
out.writeInt((iParent == NO_POS) ? 0
: iParent);
}
public void writeTranslate(RowOutputInterface out, IntLookup lookup) {
out.writeInt(iBalance);
writeTranslatePointer(iLeft, out, lookup);
writeTranslatePointer(iRight, out, lookup);
writeTranslatePointer(iParent, out, lookup);
}
private static void writeTranslatePointer(int pointer,
RowOutputInterface out, IntLookup lookup) {
int newPointer = 0;
if (pointer != NodeAVL.NO_POS) {
newPointer = lookup.lookupFirstEqual(pointer);
}
out.writeInt(newPointer);
}
}