/*
* 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.query.QueryParser;
import com.caucho.amber.table.AmberTable;
import com.caucho.amber.type.AmberType;
import com.caucho.amber.type.BeanType;
import com.caucho.amber.type.EntityType;
import com.caucho.util.CharBuffer;
/**
* Bound identifier expression.
*/
public class IdExpr extends AbstractPathExpr {
private FromItem _fromItem;
/**
* Creates a new unbound id expression.
*/
public IdExpr(FromItem fromItem)
{
_fromItem = fromItem;
//if (fromItem.getEntityType() == null)
// throw new NullPointerException();
}
/**
* Returns the name.
*/
String getId()
{
return _fromItem.getName();
}
/**
* Returns the from item
*/
public FromItem getFromItem()
{
return _fromItem;
}
/**
* Returns the table
*/
AmberTable getTable()
{
return _fromItem.getTable();
}
/**
* Returns the from item
*/
public FromItem getChildFromItem()
{
return getFromItem();
}
/**
* Returns the entity class.
*/
public BeanType getTargetType()
{
return _fromItem.getEntityType();
}
/**
* Binds the expression as a select item.
*/
public AmberExpr bindSelect(QueryParser parser)
{
return this;
}
/**
* Binds the expression as a select item.
*/
public FromItem bindSubPath(QueryParser parser)
{
return _fromItem;
}
/**
* Creates a load expression.
*/
@Override
public LoadExpr createLoad()
{
return new LoadEntityExpr(this);
}
/**
* Returns true if the expression uses the from item.
*/
public boolean usesFrom(FromItem from, int type, boolean isNot)
{
return (type == IS_INNER_JOIN && _fromItem == from);
}
/**
* Returns true if the expression uses the from item.
*/
public AmberExpr replaceJoin(JoinExpr join)
{
return join.replace(this);
}
/**
* Generates the where expression.
*/
public void generateWhere(CharBuffer cb)
{
generateInternalWhere(cb, true);
}
/**
* Generates the (update) where expression.
*/
public void generateUpdateWhere(CharBuffer cb)
{
generateInternalWhere(cb, false);
}
/**
* Generates the having expression.
*/
public void generateHaving(CharBuffer cb)
{
generateWhere(cb);
}
public String toString()
{
return getId();
}
public int hashCode()
{
return _fromItem.hashCode();
}
public boolean equals(Object o)
{
if (o == null || ! getClass().equals(o.getClass()))
return false;
IdExpr id = (IdExpr) o;
return _fromItem.equals(id._fromItem);
}
//
// private
private void generateInternalWhere(CharBuffer cb,
boolean select)
{
if (select) {
cb.append(_fromItem.getName());
cb.append('.');
}
EntityType entityType = (EntityType) getTargetType();
cb.append(entityType.getId().getColumns().get(0).getName());
}
}