|
HSQLDB example source code file (Row.java)
The HSQLDB Row.java source code/* * For work developed by the HSQL Development Group: * * Copyright (c) 2001-2010, 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. * * * * For work originally developed by the Hypersonic SQL Group: * * 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. */ 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; } } Other HSQLDB examples (source code examples)Here is a short list of links related to this HSQLDB Row.java source code file: |
... this post is sponsored by my books ... | |
#1 New Release! |
FP Best Seller |
Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.
A percentage of advertising revenue from
pages under the /java/jwarehouse
URI on this website is
paid back to open source projects.