/* * The contents of this file are subject to the Mozilla Public License * Version 1.1 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See * the License for the specific language governing rights and limitations * under the License. * * The Original Code is the Kowari Metadata Store. * * The Initial Developer of the Original Code is Plugged In Software Pty * Ltd (http://www.pisoftware.com, mailto:info@pisoftware.com). Portions * created by Plugged In Software Pty Ltd are Copyright (C) 2001,2002 * Plugged In Software Pty Ltd. All Rights Reserved. * * Contributor(s): N/A. * * [NOTE: The text of this Exhibit A may differ slightly from the text * of the notices in the Source Code files of the Original Code. You * should use the text of this Exhibit A rather than the text found in the * Original Code Source Code for Your Modifications.] * */ package org.mulgara.store.tuples; // Java 2 standard packages import java.util.*; // Locally written packages import org.mulgara.query.TuplesException; import org.mulgara.query.Variable; /** * {@link Tuples} materialized in memory. Especially convenient for use in test cases. * * @created 2003-01-10 * * @author <a href="http://staff.pisoftware.com/raboczi">Simon Raboczi</a> * * @version $Revision: 1.9 $ * * @modified $Date: 2005/01/05 04:59:10 $ * * @maintenanceAuthor $Author: newmana $ * * @company <A href="mailto:info@PIsoftware.com">Plugged In Software</A> * * @copyright © 2003 <A href="http://www.PIsoftware.com/">Plugged In * Software Pty Ltd</A> * * @licence <a href="{@docRoot}/../../LICENCE">Mozilla Public License v1.1</a> */ public class MemoryTuples extends AbstractTuples { /** * A tuples with zero rows and zero columns. */ static Tuples EMPTY = new MemoryTuples(); /** * Description of the Field */ private int row = 0; /** * Description of the Field */ private final List<Map<Variable,Long>> termList; /** * Description of the Field */ private final List<Variable> variableList; /** * Description of the Field */ private Map<Variable,Long> rowMap = null; /** * Description of the Field */ private Map<Variable,Long> lastMap = new HashMap<Variable,Long>(); /** * The number of columns in common for sort order. */ private long[] prefix; private Tuples tuples; /** * Generate an empty expression. */ public MemoryTuples() { termList = new ArrayList<Map<Variable,Long>>(); variableList = new ArrayList<Variable>(); } /** * Generate a new tuples. * * @param variable Variable variable */ public MemoryTuples(Variable variable) { this(); // Add the variables to the list if it doesn't already. if (!variableList.contains(variable)) { variableList.add(variable); setVariables(variableList); } } /** * Generate a new assignment. * * @param variable PARAMETER TO DO * @param value PARAMETER TO DO */ public MemoryTuples(Variable variable, long value) { this(); or(variable, value); } /** * Copy constructor. * * @param tuples the instance to copy * @throws TuplesException if the <var>tuples</var> can't be read */ MemoryTuples(Tuples tuples) throws TuplesException { this(); Variable[] v = tuples.getVariables(); assert v != null; tuples.beforeFirst(); boolean hasNext = tuples.next(); while (hasNext) { or(); for (int i = 0; i < v.length; i++) { long l = tuples.getColumnValue(i); if (l != Tuples.UNBOUND) { and(v[i], l); } } hasNext = tuples.next(); } this.tuples = tuples; } /** * Test tuples are always materialized as they represent in memory tuples. * * @return always true as test tuples are represented in memory. */ public boolean isMaterialized() { return true; } public List<Tuples> getOperands() { if (tuples != null) { return Collections.singletonList(tuples); } else { return Collections.emptyList(); } } /** * Gets the ColumnValue attribute of the MemoryTuples object * * @param column PARAMETER TO DO * @return The ColumnValue value * @throws TuplesException EXCEPTION TO DO */ public long getColumnValue(int column) throws TuplesException { if (rowMap == null) { throw new TuplesException("No column values; not on a row"); } if ( (column < 0) || (column >= variableList.size())) { throw new TuplesException("Invalid column: " + column); } Long value = (Long) rowMap.get(variableList.get(column)); return (value == null) ? Tuples.UNBOUND : value.longValue(); } /** * Gets the RowCount attribute of the MemoryTuples object * * @return The RowCount value */ public long getRowCount() { return termList.size(); } public long getRowUpperBound() { return getRowCount(); } public long getRowExpectedCount() { return getRowCount(); } public boolean isEmpty() throws TuplesException { return termList.isEmpty(); } /** * This method isn't really implemented; it just assumes all columns might be * unbound. * @return <code>true</code> */ public boolean isColumnEverUnbound(int column) throws TuplesException { return true; } /** * Generate a new assignment and conjoin it with the current final term. * * @param variable PARAMETER TO DO * @param value PARAMETER TO DO * @return RETURNED VALUE TO DO */ public MemoryTuples and(Variable variable, long value) { if (value == Tuples.UNBOUND) { // do nothing return this; } if (lastMap.containsKey(variable)) { throw new IllegalArgumentException(variable + " already assigned!"); } // Add the variables to the list if it doesn't already. if (!variableList.contains(variable)) { variableList.add(variable); setVariables(variableList); } assert value != Tuples.UNBOUND; lastMap.put(variable, new Long(value)); return this; } /** * METHOD TO DO * * @param variable PARAMETER TO DO * @param value PARAMETER TO DO * @return RETURNED VALUE TO DO */ public MemoryTuples or(Variable variable, long value) { return or().and(variable, value); } // // Methods implementing Tuples interface // /** * METHOD TO DO * * @param prefix PARAMETER TO DO * @param suffixTruncation PARAMETER TO DO * @throws TuplesException EXCEPTION TO DO */ public void beforeFirst(long[] prefix, int suffixTruncation) throws TuplesException { if (suffixTruncation != 0) { throw new TuplesException("Suffix truncation not supported"); } row = 0; rowMap = null; this.prefix = prefix; } /** * METHOD TO DO * * @return RETURNED VALUE TO DO * @throws TuplesException EXCEPTION TO DO */ public boolean next() throws TuplesException { A:while (advance()) { for (int i = 0; i < prefix.length; i++) { assert prefix[i] != Tuples.UNBOUND; if (prefix[i] != getColumnValue(getColumnIndex(getVariables()[i]))) { continue A; } } return true; } return false; } public boolean hasNoDuplicates() { return false; } // // Methods overriding the Object class // /** * METHOD TO DO * * @return RETURNED VALUE TO DO */ public Object clone() { MemoryTuples t = (MemoryTuples)super.clone(); // deep clone the variables Variable[] vars = getVariables(); if (vars != null && vars.length > 0) { t.setVariables(getVariables()); } t.tuples = null; return t; } /** * METHOD TO DO * */ public void close() { // NO-OP } /** * Generate a new assignment and disjoin it as the new final term. * * @return RETURNED VALUE TO DO */ private MemoryTuples or() { lastMap = new HashMap<Variable,Long>(); termList.add(lastMap); return this; } /** * METHOD TO DO * * @return RETURNED VALUE TO DO */ private boolean advance() { assert row >= 0; assert row <= termList.size(); if (row == termList.size()) { rowMap = null; return false; } else { assert row < termList.size(); rowMap = (Map<Variable,Long>) termList.get(row); row++; return true; } } }