Hibernate example source code file (SQLFunction.java)

This example Hibernate source code file (SQLFunction.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

list, mapping, mapping, queryexception, queryexception, sessionfactoryimplementor, sessionfactoryimplementor, sqlfunction, sqlfunction, string, type, util

The Hibernate SQLFunction.java source code

/*
 * 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.List;
import org.hibernate.QueryException;
import org.hibernate.engine.spi.Mapping;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.type.Type;

/**
 * Provides support routines for the HQL functions as used
 * in the various SQL Dialects
 *
 * Provides an interface for supporting various HQL functions that are
 * translated to SQL. The Dialect and its sub-classes use this interface to
 * provide details required for processing of the function.
 *
 * @author David Channon
 * @author Steve Ebersole
 */
public interface SQLFunction {
	/**
	 * Does this function have any arguments?
	 *
	 * @return True if the function expects to have parameters; false otherwise.
	 */
	public boolean hasArguments();

	/**
	 * If there are no arguments, are parentheses required?
	 *
	 * @return True if a no-arg call of this function requires parentheses.
	 */
	public boolean hasParenthesesIfNoArguments();

	/**
	 * The return type of the function.  May be either a concrete type which is preset, or variable depending upon
	 * the type of the first function argument.
	 * <p/>
	 * Note, the 'firstArgumentType' parameter should match the one passed into {@link #render}
	 *
	 * @param firstArgumentType The type of the first argument
	 * @param mapping The mapping source.
	 *
	 * @return The type to be expected as a return.
	 *
	 * @throws org.hibernate.QueryException Indicates an issue resolving the return type.
	 */
	public Type getReturnType(Type firstArgumentType, Mapping mapping) throws QueryException;


	/**
	 * Render the function call as SQL fragment.
	 * <p/>
	 * Note, the 'firstArgumentType' parameter should match the one passed into {@link #getReturnType}
	 *
	 * @param firstArgumentType The type of the first argument
	 * @param arguments The function arguments
	 * @param factory The SessionFactory
	 *
	 * @return The rendered function call
	 *
	 * @throws org.hibernate.QueryException Indicates a problem rendering the
	 * function call.
	 */
	public String render(Type firstArgumentType, List arguments, SessionFactoryImplementor factory) throws QueryException;
}