/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2011, 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.engine.internal;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import org.hibernate.InstantiationException;
import org.hibernate.MappingException;
import org.hibernate.engine.spi.IdentifierValue;
import org.hibernate.engine.spi.VersionValue;
import org.hibernate.property.Getter;
import org.hibernate.type.IdentifierType;
import org.hibernate.type.PrimitiveType;
import org.hibernate.type.Type;
import org.hibernate.type.VersionType;
/**
* Helper for dealing with unsaved value handling
*
* @author Gavin King
*/
public class UnsavedValueFactory {
/**
* Instantiate a class using the provided Constructor
*
* @param constructor The constructor
*
* @return The instantiated object
*
* @throws InstantiationException if something went wrong
*/
private static Object instantiate(Constructor constructor) {
try {
return constructor.newInstance();
}
catch (Exception e) {
throw new InstantiationException( "could not instantiate test object", constructor.getDeclaringClass(), e );
}
}
/**
* Return an IdentifierValue for the specified unsaved-value. If none is specified,
* guess the unsaved value by instantiating a test instance of the class and
* reading it's id property, or if that is not possible, using the java default
* value for the type
*
* @param unsavedValue The mapping defined unsaved value
* @param identifierGetter The getter for the entity identifier attribute
* @param identifierType The mapping type for the identifier
* @param constructor The constructor for the entity
*
* @return The appropriate IdentifierValue
*/
public static IdentifierValue getUnsavedIdentifierValue(
String unsavedValue,
Getter identifierGetter,
Type identifierType,
Constructor constructor) {
if ( unsavedValue == null ) {
if ( identifierGetter != null && constructor != null ) {
// use the id value of a newly instantiated instance as the unsaved-value
final Serializable defaultValue = (Serializable) identifierGetter.get( instantiate( constructor ) );
return new IdentifierValue( defaultValue );
}
else if ( identifierGetter != null && (identifierType instanceof PrimitiveType) ) {
final Serializable defaultValue = ( (PrimitiveType) identifierType ).getDefaultValue();
return new IdentifierValue( defaultValue );
}
else {
return IdentifierValue.NULL;
}
}
else if ( "null".equals( unsavedValue ) ) {
return IdentifierValue.NULL;
}
else if ( "undefined".equals( unsavedValue ) ) {
return IdentifierValue.UNDEFINED;
}
else if ( "none".equals( unsavedValue ) ) {
return IdentifierValue.NONE;
}
else if ( "any".equals( unsavedValue ) ) {
return IdentifierValue.ANY;
}
else {
try {
return new IdentifierValue( (Serializable) ( (IdentifierType) identifierType ).stringToObject( unsavedValue ) );
}
catch ( ClassCastException cce ) {
throw new MappingException( "Bad identifier type: " + identifierType.getName() );
}
catch ( Exception e ) {
throw new MappingException( "Could not parse identifier unsaved-value: " + unsavedValue );
}
}
}
/**
* Return an IdentifierValue for the specified unsaved-value. If none is specified,
* guess the unsaved value by instantiating a test instance of the class and
* reading it's version property value, or if that is not possible, using the java default
* value for the type
*
* @param versionUnsavedValue The mapping defined unsaved value
* @param versionGetter The version attribute getter
* @param versionType The mapping type for the version
* @param constructor The constructor for the entity
*
* @return The appropriate VersionValue
*/
public static VersionValue getUnsavedVersionValue(
String versionUnsavedValue,
Getter versionGetter,
VersionType versionType,
Constructor constructor) {
if ( versionUnsavedValue == null ) {
if ( constructor!=null ) {
final Object defaultValue = versionGetter.get( instantiate( constructor ) );
// if the version of a newly instantiated object is not the same
// as the version seed value, use that as the unsaved-value
return versionType.isEqual( versionType.seed( null ), defaultValue )
? VersionValue.UNDEFINED
: new VersionValue( defaultValue );
}
else {
return VersionValue.UNDEFINED;
}
}
else if ( "undefined".equals( versionUnsavedValue ) ) {
return VersionValue.UNDEFINED;
}
else if ( "null".equals( versionUnsavedValue ) ) {
return VersionValue.NULL;
}
else if ( "negative".equals( versionUnsavedValue ) ) {
return VersionValue.NEGATIVE;
}
else {
// this should not happen since the DTD prevents it
throw new MappingException( "Could not parse version unsaved-value: " + versionUnsavedValue );
}
}
private UnsavedValueFactory() {
}
}