001: /*
002: * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
003: *
004: * This file is part of Resin(R) Open Source
005: *
006: * Each copy or derived work must preserve the copyright notice and this
007: * notice unmodified.
008: *
009: * Resin Open Source is free software; you can redistribute it and/or modify
010: * it under the terms of the GNU General Public License as published by
011: * the Free Software Foundation; either version 2 of the License, or
012: * (at your option) any later version.
013: *
014: * Resin Open Source is distributed in the hope that it will be useful,
015: * but WITHOUT ANY WARRANTY; without even the implied warranty of
016: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
017: * of NON-INFRINGEMENT. See the GNU General Public License for more
018: * details.
019: *
020: * You should have received a copy of the GNU General Public License
021: * along with Resin Open Source; if not, write to the
022: * Free SoftwareFoundation, Inc.
023: * 59 Temple Place, Suite 330
024: * Boston, MA 02111-1307 USA
025: *
026: * @author Scott Ferguson
027: */
028:
029: package com.caucho.db.sql;
030:
031: import com.caucho.db.jdbc.GeneratedKeysResultSet;
032: import com.caucho.db.table.Column;
033: import com.caucho.db.table.Table;
034: import com.caucho.log.Log;
035:
036: import java.sql.SQLException;
037: import java.util.logging.Logger;
038:
039: class AutoIncrementExpr extends Expr {
040: private static final Logger log = Log.open(AutoIncrementExpr.class);
041:
042: private Table _table;
043:
044: AutoIncrementExpr(Table table) {
045: _table = table;
046: }
047:
048: /**
049: * Returns the type of the expression.
050: */
051: public Class getType() {
052: return long.class;
053: }
054:
055: /**
056: * Evaluates the expression as a long
057: *
058: * @param row the current data tuple
059: *
060: * @return the long value
061: */
062: public long evalLong(QueryContext context) throws SQLException {
063: long value = _table.nextAutoIncrement(context);
064:
065: GeneratedKeysResultSet keysRS = context
066: .getGeneratedKeysResultSet();
067:
068: if (keysRS != null) {
069: Column column = _table.getAutoIncrementColumn();
070:
071: keysRS.setColumn(1, column);
072: keysRS.setLong(1, value);
073: }
074:
075: return value;
076: }
077:
078: /**
079: * Evaluates the expression as a double
080: *
081: * @param row the current data tuple
082: *
083: * @return the double value
084: */
085: public double evalDouble(QueryContext context) throws SQLException {
086: return evalLong(context);
087: }
088:
089: /**
090: * Evaluates the expression as a string
091: *
092: * @param row the current data tuple
093: *
094: * @return the string value
095: */
096: public String evalString(QueryContext context) throws SQLException {
097: return String.valueOf(evalLong(context));
098: }
099:
100: public String toString() {
101: return "auto_increment()";
102: }
103: }
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