/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.dialect.function;
import java.util.ArrayList;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.hibernate.engine.SessionFactoryImplementor;
/**
* Delegate for handling function "templates".
*
* @author Steve Ebersole
*/
public class TemplateRenderer {
private static final Logger log = LoggerFactory.getLogger( TemplateRenderer.class );
private final String template;
private final String[] chunks;
private final int[] paramIndexes;
public TemplateRenderer(String template) {
this.template = template;
List chunkList = new ArrayList();
List paramList = new ArrayList();
StringBuffer chunk = new StringBuffer( 10 );
StringBuffer index = new StringBuffer( 2 );
for ( int i = 0; i < template.length(); ++i ) {
char c = template.charAt( i );
if ( c == '?' ) {
chunkList.add( chunk.toString() );
chunk.delete( 0, chunk.length() );
while ( ++i < template.length() ) {
c = template.charAt( i );
if ( Character.isDigit( c ) ) {
index.append( c );
}
else {
chunk.append( c );
break;
}
}
paramList.add( Integer.valueOf( index.toString() ) );
index.delete( 0, index.length() );
}
else {
chunk.append( c );
}
}
if ( chunk.length() > 0 ) {
chunkList.add( chunk.toString() );
}
chunks = (String[]) chunkList.toArray( new String[chunkList.size()] );
paramIndexes = new int[paramList.size()];
for ( int i = 0; i < paramIndexes.length; ++i ) {
paramIndexes[i] = ( (Integer) paramList.get( i ) ).intValue();
}
}
public String getTemplate() {
return template;
}
public int getAnticipatedNumberOfArguments() {
return paramIndexes.length;
}
public String render(List args, SessionFactoryImplementor factory) {
int numberOfArguments = args.size();
if ( getAnticipatedNumberOfArguments() > 0 && numberOfArguments != getAnticipatedNumberOfArguments() ) {
log.warn(
"Function template anticipated " + getAnticipatedNumberOfArguments()
+ " arguments, but " + numberOfArguments + " arguments encountered"
);
}
StringBuffer buf = new StringBuffer();
for ( int i = 0; i < chunks.length; ++i ) {
if ( i < paramIndexes.length ) {
final int index = paramIndexes[i] - 1;
final Object arg = index < numberOfArguments ? args.get( index ) : null;
if ( arg != null ) {
buf.append( chunks[i] ).append( arg );
}
}
else {
buf.append( chunks[i] );
}
}
return buf.toString();
}
}