/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
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, Steve Ebersole/**
 * 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?
Returns:
True if the function expects to have parameters; false otherwise./**
	 * 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?
Returns:
True if a no-arg call of this function requires parentheses./**
	 * 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.
 Note, the 'firstArgumentType' parameter should match the one passed into render 
Params:
firstArgumentType – The type of the first argument
mapping – The mapping source.
Throws:
QueryException – Indicates an issue resolving the return type.
Returns:
The type to be expected as a return./**
	 * 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.
 Note, the 'firstArgumentType' parameter should match the one passed into getReturnType 
Params:
firstArgumentType – The type of the first argument
arguments – The function arguments
factory – The SessionFactory
Throws:
QueryException – Indicates a problem rendering the
function call.
Returns:
The rendered function call/**
	 * 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;
}