Hibernate example source code file (AliasToBeanConstructorResultTransformer.java)

This example Hibernate source code file (AliasToBeanConstructorResultTransformer.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

aliastobeanconstructorresulttransformer, aliastobeanconstructorresulttransformer, constructor, constructor, exception, list, object, object, queryexception, queryexception, reflection, resulttransformer, string, util

The Hibernate AliasToBeanConstructorResultTransformer.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC 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 Middleware LLC.
 *
 * 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.transform;
import java.lang.reflect.Constructor;
import java.util.List;
import org.hibernate.QueryException;

/**
 * Wraps the tuples in a constructor call.
 *
 * todo : why Alias* in the name???
 */
public class AliasToBeanConstructorResultTransformer implements ResultTransformer {

	private final Constructor constructor;

	/**
	 * Instantiates a AliasToBeanConstructorResultTransformer.
	 *
	 * @param constructor The contructor in which to wrap the tuples.
	 */
	public AliasToBeanConstructorResultTransformer(Constructor constructor) {
		this.constructor = constructor;
	}
	
	/**
	 * Wrap the incoming tuples in a call to our configured constructor.
	 */
	public Object transformTuple(Object[] tuple, String[] aliases) {
		try {
			return constructor.newInstance( tuple );
		}
		catch ( Exception e ) {
			throw new QueryException( 
					"could not instantiate class [" + constructor.getDeclaringClass().getName() + "] from tuple",
					e
			);
		}
	}

	/**
	 * {@inheritDoc}
	 */
	public List transformList(List collection) {
		return collection;
	}

	/**
	 * Define our hashCode by our defined constructor's hasCode.
	 *
	 * @return Our defined ctor hashCode
	 */
	public int hashCode() {
		return constructor.hashCode();
	}

	/**
	 * 2 AliasToBeanConstructorResultTransformer are considered equal if they have the same
	 * defined constructor.
	 *
	 * @param other The other instance to check for equality.
	 * @return True if both have the same defined constuctor; false otherwise.
	 */
	public boolean equals(Object other) {
		return other instanceof AliasToBeanConstructorResultTransformer
				&& constructor.equals( ( ( AliasToBeanConstructorResultTransformer ) other ).constructor );
	}
}