001: /*
002: * $Id: BaseBTreeIndex.java,v 1.6 2005/03/12 02:10:41 ahimanikya Exp $
003: * =======================================================================
004: * Copyright (c) 2002-2005 Axion Development Team. All rights reserved.
005: *
006: * Redistribution and use in source and binary forms, with or without
007: * modification, are permitted provided that the following conditions
008: * are met:
009: *
010: * 1. Redistributions of source code must retain the above
011: * copyright notice, this list of conditions and the following
012: * disclaimer.
013: *
014: * 2. Redistributions in binary form must reproduce the above copyright
015: * notice, this list of conditions and the following disclaimer in
016: * the documentation and/or other materials provided with the
017: * distribution.
018: *
019: * 3. The names "Tigris", "Axion", nor the names of its contributors may
020: * not be used to endorse or promote products derived from this
021: * software without specific prior written permission.
022: *
023: * 4. Products derived from this software may not be called "Axion", nor
024: * may "Tigris" or "Axion" appear in their names without specific prior
025: * written permission.
026: *
027: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
028: * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
029: * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
030: * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
031: * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
032: * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
033: * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
034: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
035: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
036: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
037: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
038: * =======================================================================
039: */
040:
041: package org.axiondb.engine.indexes;
042:
043: import java.io.File;
044:
045: import org.axiondb.AxionException;
046: import org.axiondb.Column;
047: import org.axiondb.Function;
048: import org.axiondb.Index;
049: import org.axiondb.functions.EqualFunction;
050: import org.axiondb.functions.GreaterThanFunction;
051: import org.axiondb.functions.GreaterThanOrEqualFunction;
052: import org.axiondb.functions.IsNotNullFunction;
053: import org.axiondb.functions.IsNullFunction;
054: import org.axiondb.functions.LessThanFunction;
055: import org.axiondb.functions.LessThanOrEqualFunction;
056:
057: /**
058: * Abstract base implementation for B-Tree based {@link Index indices}.
059: *
060: * @version $Revision: 1.6 $ $Date: 2005/03/12 02:10:41 $
061: * @author Dave Pekarek Krohn
062: */
063: public abstract class BaseBTreeIndex extends BaseIndex implements Index {
064:
065: public BaseBTreeIndex(String name, Column column, boolean unique) {
066: super (name, column, unique);
067: }
068:
069: public String getType() {
070: return Index.BTREE;
071: }
072:
073: public void save(File dataDirectory) throws AxionException {
074: getIndexLoader().saveIndex(this , dataDirectory);
075: }
076:
077: public void saveAfterTruncate(File dataDirectory)
078: throws AxionException {
079: getIndexLoader().saveIndexAfterTruncate(this , dataDirectory);
080: }
081:
082: public boolean supportsFunction(Function fn) {
083: if (fn instanceof EqualFunction) {
084: if (isUnique()) {
085: return true;
086: }
087: return getIndexedColumn().getDataType().supportsSuccessor();
088: } else if (fn instanceof LessThanFunction) {
089: return true;
090: } else if (fn instanceof LessThanOrEqualFunction) {
091: return getIndexedColumn().getDataType().supportsSuccessor();
092: } else if (fn instanceof GreaterThanFunction) {
093: return true;
094: } else if (fn instanceof GreaterThanOrEqualFunction) {
095: return getIndexedColumn().getDataType().supportsSuccessor();
096: } else if (fn instanceof IsNotNullFunction) {
097: return true;
098: } else if (fn instanceof IsNullFunction) {
099: return true;
100: } else {
101: return false;
102: }
103: }
104:
105: }
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