/*
* 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.tuple;
import java.io.IOException;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.hibernate.InstantiationException;
import org.hibernate.PropertyNotFoundException;
import org.hibernate.bytecode.ReflectionOptimizer;
import org.hibernate.mapping.PersistentClass;
import org.hibernate.mapping.Component;
import org.hibernate.util.ReflectHelper;
/**
* Defines a POJO-based instantiator for use from the tuplizers.
*/
public class PojoInstantiator implements Instantiator, Serializable {
private static final Logger log = LoggerFactory.getLogger(PojoInstantiator.class);
private transient Constructor constructor;
private final Class mappedClass;
private final transient ReflectionOptimizer.InstantiationOptimizer optimizer;
private final boolean embeddedIdentifier;
private final Class proxyInterface;
public PojoInstantiator(Component component, ReflectionOptimizer.InstantiationOptimizer optimizer) {
this.mappedClass = component.getComponentClass();
this.optimizer = optimizer;
this.proxyInterface = null;
this.embeddedIdentifier = false;
try {
constructor = ReflectHelper.getDefaultConstructor(mappedClass);
}
catch ( PropertyNotFoundException pnfe ) {
log.info(
"no default (no-argument) constructor for class: " +
mappedClass.getName() +
" (class must be instantiated by Interceptor)"
);
constructor = null;
}
}
public PojoInstantiator(PersistentClass persistentClass, ReflectionOptimizer.InstantiationOptimizer optimizer) {
this.mappedClass = persistentClass.getMappedClass();
this.proxyInterface = persistentClass.getProxyInterface();
this.embeddedIdentifier = persistentClass.hasEmbeddedIdentifier();
this.optimizer = optimizer;
try {
constructor = ReflectHelper.getDefaultConstructor( mappedClass );
}
catch ( PropertyNotFoundException pnfe ) {
log.info(
"no default (no-argument) constructor for class: " +
mappedClass.getName() +
" (class must be instantiated by Interceptor)"
);
constructor = null;
}
}
private void readObject(java.io.ObjectInputStream stream)
throws ClassNotFoundException, IOException {
stream.defaultReadObject();
constructor = ReflectHelper.getDefaultConstructor(mappedClass);
}
public Object instantiate() {
if ( ReflectHelper.isAbstractClass(mappedClass) ) {
throw new InstantiationException( "Cannot instantiate abstract class or interface: ", mappedClass );
}
else if ( optimizer != null ) {
return optimizer.newInstance();
}
else if ( constructor == null ) {
throw new InstantiationException( "No default constructor for entity: ", mappedClass );
}
else {
try {
return constructor.newInstance( null );
}
catch ( Exception e ) {
throw new InstantiationException( "Could not instantiate entity: ", mappedClass, e );
}
}
}
public Object instantiate(Serializable id) {
final boolean useEmbeddedIdentifierInstanceAsEntity = embeddedIdentifier &&
id != null &&
id.getClass().equals(mappedClass);
return useEmbeddedIdentifierInstanceAsEntity ? id : instantiate();
}
public boolean isInstance(Object object) {
return mappedClass.isInstance(object) ||
( proxyInterface!=null && proxyInterface.isInstance(object) ); //this one needed only for guessEntityMode()
}
}