/* 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 org.hsqldb.RowAVLDisk;
import org.hsqldb.Row;
import org.hsqldb.persist.CachedObject;
import org.hsqldb.persist.PersistentStore;
import org.hsqldb.rowio.RowOutputInterface;
import org.hsqldb.lib.IntLookup;
// 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
// fredt@users 20021215 - doc 1.7.2 - javadoc comments
/**
* The parent for all AVL node implementations. Subclasses of Node vary
* in the way they hold
* references to other Nodes in the AVL tree, or to their Row data.<br>
*
* nNext links the Node objects belonging to different indexes for each
* table row. It is used solely by Row to locate the node belonging to a
* particular index.<br>
*
* 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 abstract class NodeAVL implements CachedObject {
static final int NO_POS = RowAVLDisk.NO_POS;
public int iBalance; // currently, -2 means 'deleted'
public NodeAVL nNext; // node of next index (nNext==null || nNext.iId=iId+1)
/**
* This method unlinks the Node from the other Nodes in the same Index
* and from the Row.
*
* It must keep the links between the Nodes in different Indexes.
*/
abstract public void delete();
public boolean isMemory() {
return true;
}
/**
* File offset of Node. Used with CachedRow objects only
*/
abstract public int getPos();
/**
* Return the Row Object that is linked to this Node.
*/
abstract Row getRow(PersistentStore store);
/**
* Getters and setters for AVL index operations.
*/
abstract boolean isLeft(NodeAVL node);
abstract boolean isRight(NodeAVL node);
abstract NodeAVL getLeft(PersistentStore store);
abstract NodeAVL setLeft(PersistentStore store, NodeAVL n);
abstract NodeAVL getRight(PersistentStore store);
abstract NodeAVL setRight(PersistentStore store, NodeAVL n);
abstract NodeAVL getParent(PersistentStore store);
abstract NodeAVL setParent(PersistentStore store, NodeAVL n);
abstract int getBalance();
abstract public NodeAVL setBalance(PersistentStore store, int b);
abstract boolean isRoot();
abstract boolean isFromLeft(PersistentStore store);
abstract boolean equals(NodeAVL n);
public void updateAccessCount(int count) {}
public int getAccessCount() {
return 0;
}
public void setStorageSize(int size) {}
public int getStorageSize() {
return 0;
}
public void setPos(int pos) {}
public boolean hasChanged() {
return false;
}
public boolean isKeepInMemory() {
return false;
}
;
public boolean keepInMemory(boolean keep) {
return true;
}
public boolean isInMemory() {
return false;
}
abstract public void setInMemory(boolean in);
public void restore() {}
public void destroy() {}
public int getRealSize(RowOutputInterface out) {
return 0;
}
abstract public void write(RowOutputInterface out);
public void write(RowOutputInterface out, IntLookup lookup) {}
}