/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.amber.expr;
import com.caucho.amber.query.FromItem;
import com.caucho.amber.table.AmberColumn;
/**
* Bound identifier expression.
*/
public class KeyColumnExpr extends ColumnExpr {
/**
* Creates a new unbound id expression.
*/
public KeyColumnExpr(PathExpr parent, AmberColumn column)
{
super(parent, column);
}
/**
* Binds the expression as a select item.
*/
/*
public AmberExpr bindSelect(QueryParser parser)
{
return this;
}
*/
/**
* Returns true if the expression uses the from item.
*/
public boolean usesFrom(FromItem from, int type, boolean isNot)
{
if (_parent instanceof ManyToOneExpr) {
// jpa/0h1c
return false;
}
FromItem fromItem = _parent.getChildFromItem();
// ejb/0j00 vs ejb/0h13 vs ejb/0t00
if (type == IS_INNER_JOIN)
return (from == fromItem);
else
return false;
}
/**
* Replaces linked join to eliminate a table.
*/
public AmberExpr replaceJoin(JoinExpr join)
{
return join.replace(this);
}
}