/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ejb.plugins.cmp.jdbc;
import org.jboss.deployment.DeploymentException;
import org.jboss.ejb.plugins.cmp.ejbql.Catalog;
import org.jboss.ejb.plugins.cmp.jdbc.bridge.JDBCEntityBridge;
import org.jboss.ejb.plugins.cmp.jdbc.bridge.JDBCCMPFieldBridge;
import org.jboss.ejb.plugins.cmp.jdbc.metadata.JDBCQueryMetaData;
import org.jboss.ejb.plugins.cmp.jdbc.metadata.JDBCDeclaredQueryMetaData;
import org.jboss.ejb.plugins.cmp.jdbc.metadata.JDBCReadAheadMetaData;
/**
* This class generates a query based on the delcared-sql xml specification.
*
* @author <a href="mailto:dain@daingroup.com">Dain Sundstrom</a>
* @author <a href="mailto:rickard.oberg@telkel.com">Rickard Oberg</a>
* @author <a href="mailto:marc.fleury@telkel.com">Marc Fleury</a>
* @author <a href="mailto:shevlandj@kpi.com.au">Joe Shevland</a>
* @author <a href="mailto:justin@j-m-f.demon.co.uk">Justin Forder</a>
* @author <a href="mailto:michel.anke@wolmail.nl">Michel de Groot</a>
* @author <a href="danch@nvisia.com">danch (Dan Christopherson</a>
* @author <a href="alex@jboss.org">Alex Loubyansky</a>
* @version $Revision: 81030 $
*/
public final class JDBCDeclaredSQLQuery extends JDBCAbstractQueryCommand
{
private final JDBCDeclaredQueryMetaData metadata;
/**
* Creted a defined finder command based on the information
* in a declared-sql declaration.
*/
public JDBCDeclaredSQLQuery(JDBCStoreManager manager,
JDBCQueryMetaData q)
throws DeploymentException
{
super(manager, q);
metadata = (JDBCDeclaredQueryMetaData)q;
// set the select object (either selectEntity or selectField)
initSelectObject(manager);
// set the preload fields
JDBCReadAheadMetaData readAhead = metadata.getReadAhead();
JDBCEntityBridge selectEntity = getSelectEntity();
if(selectEntity != null && readAhead.isOnFind())
{
setEagerLoadGroup(readAhead.getEagerLoadGroup());
}
// set the sql and parameters
String sql = buildSQL();
setSQL(parseParameters(sql));
}
/**
* Initializes the entity or field to be selected.
* @throws DeploymentException if the specified object is invalid or
* non-existant
*/
private void initSelectObject(JDBCStoreManager manager)
throws DeploymentException
{
String entityName = metadata.getEJBName();
// if no name is specified we are done
if(entityName == null)
{
return;
}
Catalog catalog = manager.getCatalog();
JDBCEntityBridge entity = (JDBCEntityBridge)catalog.getEntityByEJBName(entityName);
if(entity == null)
{
throw new DeploymentException("Unknown entity: " + entityName);
}
String fieldName = metadata.getFieldName();
if(fieldName == null)
{
setSelectEntity(entity);
}
else
{
JDBCCMPFieldBridge field = entity.getCMPFieldByName(fieldName);
if(field == null)
{
throw new DeploymentException("Unknown cmp field: " + fieldName);
}
setSelectField(field);
}
}
/**
* Builds the sql statement based on the delcared-sql metadata specification.
* @return the sql statement for this query
*/
private String buildSQL()
{
StringBuffer sql = new StringBuffer(300);
sql.append(SQLUtil.SELECT);
if(metadata.isSelectDistinct())
{
sql.append(SQLUtil.DISTINCT);
}
String alias = metadata.getAlias();
String from = metadata.getFrom();
String table;
String selectList;
if(getSelectField() == null)
{
// we are selecting a full entity
table = getSelectEntity().getQualifiedTableName();
// get a list of all fields to be loaded
// put pk fields in front
String tableAlias = getTableAlias(alias, from, getSelectEntity().getTableName());
selectList = SQLUtil.getColumnNamesClause(
getSelectEntity().getPrimaryKeyFields(),
tableAlias,
new StringBuffer(35)
).toString();
if(getEagerLoadGroup() != null)
{
selectList += SQLUtil.appendColumnNamesClause(
getSelectEntity(),
getEagerLoadGroup(),
tableAlias,
new StringBuffer(35));
}
}
else
{
// we are just selecting one field
JDBCCMPFieldBridge selectField = getSelectField();
JDBCStoreManager manager = (JDBCStoreManager)getSelectField().getManager();
table = manager.getEntityBridge().getQualifiedTableName();
selectList = SQLUtil.getColumnNamesClause(
selectField, getTableAlias(alias, from, manager.getEntityBridge().getTableName()), new StringBuffer()).toString();
}
sql.append(selectList);
String additionalColumns = metadata.getAdditionalColumns();
if(additionalColumns != null)
{
sql.append(additionalColumns);
}
sql.append(SQLUtil.FROM).append(table);
if(alias != null)
{
sql.append(' ').append(alias);
}
if(from != null)
{
sql.append(' ').append(from);
}
String where = metadata.getWhere();
if(where != null && where.trim().length() > 0)
{
sql.append(SQLUtil.WHERE).append(where);
}
String order = metadata.getOrder();
if(order != null && order.trim().length() > 0)
{
sql.append(SQLUtil.ORDERBY).append(order);
}
String other = metadata.getOther();
if(other != null && other.trim().length() > 0)
{
sql.append(' ').append(other);
}
return sql.toString();
}
private static String getTableAlias(String alias, String from, String table)
{
String tableAlias;
if(alias != null)
{
tableAlias = alias;
}
else if(from != null)
{
tableAlias = table;
}
else
{
tableAlias = SQLUtil.EMPTY_STRING;
}
return tableAlias;
}
}