/* 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) 2001-2008, 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;
import org.hsqldb.lib.IntLookup;
import org.hsqldb.lib.java.JavaSystem;
import org.hsqldb.persist.CachedObject;
import org.hsqldb.rowio.RowOutputInterface;
// fredt@users 20020221 - patch 513005 by sqlbob@users (RMP)
// fredt@users 20020920 - patch 1.7.1 - refactoring to cut mamory footprint
// fredt@users 20021215 - doc 1.7.2 - javadoc comments
/**
* Base class for a database row object implementing rows for
* memory resident tables.<p>
*
* Subclass CachedRow implements rows for CACHED and TEXT tables
*
* @author Thomas Mueller (Hypersonic SQL Group)
* @version 1.8.0
* @since Hypersonic SQL
*/
public class Row implements CachedObject {
int tableId;
int iPos;
protected Object[] oData;
protected Node nPrimaryNode;
/**
* Default constructor used only in subclasses.
*/
protected Row() {}
/**
* Constructor for MEMORY table Row. The result is a Row with Nodes that
* are not yet linked with other Nodes in the AVL indexes.
*/
Row(Table t, Object[] o) throws HsqlException {
int index = t.getIndexCount();
nPrimaryNode = Node.newNode(this, 0, t);
Node n = nPrimaryNode;
for (int i = 1; i < index; i++) {
n.nNext = Node.newNode(this, i, t);
n = n.nNext;
}
tableId = t.getId();
oData = o;
}
/**
* Returns the Node for a given Index, using the ordinal position of the
* Index within the Table Object.
*/
Node getNode(int index) {
Node n = nPrimaryNode;
while (index-- > 0) {
n = n.nNext;
}
return n;
}
/**
* Returns the Node for the next Index on this database row, given the
* Node for any Index.
*/
Node getNextNode(Node n) {
if (n == null) {
n = nPrimaryNode;
} else {
n = n.nNext;
}
return n;
}
/**
* Returns the Row Object that currently represents the same database row.
* In current implementations of Row, this is always the same as the this
* Object for MEMORY tables, but could be a different Object for CachedRow
* or CachedDataRow implementation. For example the Row Object that
* represents a given database row can be freed from the Cache when other
* rows need to be loaded into the Cache. getUpdatedRow() returns a
* currently valid Row object that is in the Cache.
*/
Row getUpdatedRow() throws HsqlException {
return this;
}
/**
* Returns the array of fields in the database row.
*/
public Object[] getData() {
return oData;
}
/**
* Is used only when the database row is deleted, not when it is freed
* from the Cache.
*/
void delete() throws HsqlException {
JavaSystem.memoryRecords++;
nPrimaryNode = null;
}
void clearNodeLinks() {
Node last;
Node temp;
last = nPrimaryNode;
while (last.nNext != null) {
temp = last.nNext;
last.nNext = null;
last = temp;
}
nPrimaryNode = null;
}
boolean isCascadeDeleted() {
return nPrimaryNode == null;
}
public int getRealSize(RowOutputInterface out) {
return 0;
}
public void setStorageSize(int size) {
;
}
public int getStorageSize() {
return 0;
}
public long getId() {
return ((long) tableId << 32) + ((long) iPos);
}
public static long getId(Table table, int pos) {
return ((long) table.getId() << 32) + ((long) pos);
}
public int getPos() {
return iPos;
}
public void setPos(int pos) {
iPos = pos;
}
public boolean hasChanged() {
return false;
}
public boolean isKeepInMemory() {
return true;
}
public void keepInMemory(boolean keep) {}
public boolean isInMemory() {
return true;
}
public void setInMemory(boolean in) {}
public void write(RowOutputInterface out) {}
public void write(RowOutputInterface out, IntLookup lookup) {}
/**
* Lifetime scope of this method depends on the operations performed on
* any cached tables since this row or the parameter were constructed.
* If only deletes or only inserts have been performed, this method
* remains valid. Otherwise it can return invalid results.
*
* @param obj row to compare
* @return boolean
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof Row) {
return ((Row) obj).iPos == iPos;
}
return false;
}
/**
* Hash code is valid only until a modification to the cache
*
* @return file position of row
*/
public int hashCode() {
return iPos;
}
}