/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
* third-party contributors as indicated by either @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.ejb.criteria.expression.function;
import java.io.Serializable;
import javax.persistence.criteria.Expression;
import org.hibernate.ejb.criteria.CriteriaBuilderImpl;
import org.hibernate.ejb.criteria.CriteriaQueryCompiler;
import org.hibernate.ejb.criteria.ParameterRegistry;
import org.hibernate.ejb.criteria.Renderable;
import org.hibernate.ejb.criteria.expression.LiteralExpression;
/**
* Models the ANSI SQL <tt>SUBSTRING</tt> function.
*
* @author Steve Ebersole
*/
public class SubstringFunction
extends BasicFunctionExpression<String>
implements Serializable {
public static final String NAME = "substring";
private final Expression<String> value;
private final Expression<Integer> start;
private final Expression<Integer> length;
public SubstringFunction(
CriteriaBuilderImpl criteriaBuilder,
Expression<String> value,
Expression<Integer> start,
Expression<Integer> length) {
super( criteriaBuilder, String.class, NAME );
this.value = value;
this.start = start;
this.length = length;
}
@SuppressWarnings({ "RedundantCast" })
public SubstringFunction(
CriteriaBuilderImpl criteriaBuilder,
Expression<String> value,
Expression<Integer> start) {
this( criteriaBuilder, value, start, (Expression<Integer>)null );
}
public SubstringFunction(
CriteriaBuilderImpl criteriaBuilder,
Expression<String> value,
int start) {
this(
criteriaBuilder,
value,
new LiteralExpression<Integer>( criteriaBuilder, start )
);
}
public SubstringFunction(
CriteriaBuilderImpl criteriaBuilder,
Expression<String> value,
int start,
int length) {
this(
criteriaBuilder,
value,
new LiteralExpression<Integer>( criteriaBuilder, start ),
new LiteralExpression<Integer>( criteriaBuilder, length )
);
}
public Expression<Integer> getLength() {
return length;
}
public Expression<Integer> getStart() {
return start;
}
public Expression<String> getValue() {
return value;
}
@Override
public void registerParameters(ParameterRegistry registry) {
Helper.possibleParameter( getLength(), registry );
Helper.possibleParameter( getStart(), registry );
Helper.possibleParameter( getValue(), registry );
}
public String render(CriteriaQueryCompiler.RenderingContext renderingContext) {
StringBuilder buffer = new StringBuilder();
buffer.append( "substring(" )
.append( ( (Renderable) getValue() ).render( renderingContext ) )
.append( ',' )
.append( ( (Renderable) getStart() ).render( renderingContext ) );
if ( getLength() != null ) {
buffer.append( ',' )
.append( ( (Renderable) getLength() ).render( renderingContext ) );
}
buffer.append( ')' );
return buffer.toString();
}
}