org.hibernate.engine.IdentifierValue Maven / Gradle / Ivy
/*
* 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.engine;
import java.io.Serializable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A strategy for determining if an identifier value is an identifier of
* a new transient instance or a previously persistent transient instance.
* The strategy is determined by the unsaved-value attribute in
* the mapping file.
*
* @author Gavin King
*/
public class IdentifierValue {
private static final Logger log = LoggerFactory.getLogger(IdentifierValue.class);
private final Serializable value;
/**
* Always assume the transient instance is newly instantiated
*/
public static final IdentifierValue ANY = new IdentifierValue() {
public final Boolean isUnsaved(Serializable id) {
log.trace("id unsaved-value strategy ANY");
return Boolean.TRUE;
}
public Serializable getDefaultValue(Serializable currentValue) {
return currentValue;
}
public String toString() {
return "SAVE_ANY";
}
};
/**
* Never assume the transient instance is newly instantiated
*/
public static final IdentifierValue NONE = new IdentifierValue() {
public final Boolean isUnsaved(Serializable id) {
log.trace("id unsaved-value strategy NONE");
return Boolean.FALSE;
}
public Serializable getDefaultValue(Serializable currentValue) {
return currentValue;
}
public String toString() {
return "SAVE_NONE";
}
};
/**
* Assume the transient instance is newly instantiated if the identifier
* is null.
*/
public static final IdentifierValue NULL = new IdentifierValue() {
public final Boolean isUnsaved(Serializable id) {
log.trace("id unsaved-value strategy NULL");
return id==null ? Boolean.TRUE : Boolean.FALSE;
}
public Serializable getDefaultValue(Serializable currentValue) {
return null;
}
public String toString() {
return "SAVE_NULL";
}
};
/**
* Assume nothing.
*/
public static final IdentifierValue UNDEFINED = new IdentifierValue() {
public final Boolean isUnsaved(Serializable id) {
log.trace("id unsaved-value strategy UNDEFINED");
return null;
}
public Serializable getDefaultValue(Serializable currentValue) {
return null;
}
public String toString() {
return "UNDEFINED";
}
};
protected IdentifierValue() {
this.value = null;
}
/**
* Assume the transient instance is newly instantiated if
* its identifier is null or equal to value
*/
public IdentifierValue(Serializable value) {
this.value = value;
}
/**
* Does the given identifier belong to a new instance?
*/
public Boolean isUnsaved(Serializable id) {
if ( log.isTraceEnabled() ) log.trace("id unsaved-value: " + value);
return id==null || id.equals(value) ? Boolean.TRUE : Boolean.FALSE;
}
public Serializable getDefaultValue(Serializable currentValue) {
return value;
}
public String toString() {
return "identifier unsaved-value: " + value;
}
}