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: *
023: * Free Software Foundation, Inc.
024: * 59 Temple Place, Suite 330
025: * Boston, MA 02111-1307 USA
026: *
027: * @author Scott Ferguson
028: */
029:
030: package com.caucho.db.sql;
031:
032: import com.caucho.log.Log;
033:
034: import java.sql.SQLException;
035: import java.util.ArrayList;
036: import java.util.logging.Logger;
037:
038: class BinaryExpr extends Expr {
039: private static final Logger log = Log.open(BinaryExpr.class);
040:
041: private Expr _left;
042: private Expr _right;
043: private int _op;
044:
045: BinaryExpr(Expr left, Expr right, int op) {
046: _left = left;
047: _right = right;
048: _op = op;
049: }
050:
051: /**
052: * Binds the expression to the actual tables.
053: */
054: protected Expr bind(Query query) throws SQLException {
055: Expr newLeft = _left.bind(query);
056: Expr newRight = _right.bind(query);
057:
058: switch (_op) {
059: case '+':
060: case '-':
061: case '*':
062: case '/':
063: case '%':
064: if (newLeft.isLong() && newRight.isLong())
065: return new BinaryLongExpr(newLeft, newRight, _op);
066: else
067: return new BinaryDoubleExpr(newLeft, newRight, _op);
068: }
069:
070: throw new SQLException("can't cope: " + newLeft + " "
071: + newLeft.getType() + " " + newRight);
072: }
073:
074: /**
075: * Returns the cost based on the given FromList.
076: */
077: public long subCost(ArrayList<FromItem> fromList) {
078: return _left.subCost(fromList) + _right.subCost(fromList);
079: }
080:
081: /**
082: * Returns the type of the expression.
083: */
084: public Class getType() {
085: return Object.class;
086: }
087:
088: /**
089: * Evaluates aggregate functions during the group phase.
090: *
091: * @param state the current database tuple
092: */
093: public void evalGroup(QueryContext context) throws SQLException {
094: _left.evalGroup(context);
095: _right.evalGroup(context);
096: }
097:
098: public String toString() {
099: switch (_op) {
100: case '+':
101: return "(" + _left + " + " + _right + ")";
102:
103: case '-':
104: return "(" + _left + " - " + _right + ")";
105:
106: case '*':
107: return "(" + _left + " * " + _right + ")";
108:
109: case '/':
110: return "(" + _left + " / " + _right + ")";
111:
112: case '%':
113: return "(" + _left + " % " + _right + ")";
114:
115: default:
116: throw new IllegalStateException("can't compare");
117: }
118: }
119: }
|