//$Id: $
package org.hibernate.validator.event;
import java.lang.ref.WeakReference;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.Set;
import java.util.HashSet;
import javax.persistence.PrePersist;
import javax.persistence.PreUpdate;
import org.hibernate.validator.ClassValidator;
/**
* Java Persistence Entity Listener that validates entities on inserts or updates
* This listener needs ot be placed on each validatable entities
*
* <code>
* @Entity
* @EntityListeners(JPAValidateListener.class)
* public class Submarine {
* @NotEmpty private String name;
* ...
* }
* </code>
*
* @author Emmanuel Bernard
*/
public class JPAValidateListener {
//No need for weakReference if the event listener is loaded by the same CL than
//the entities, but in a shared env this is not the case
//TODO check that this can be hot redeployable
private static final Map<Class, WeakReference<ClassValidator>> validators;
private static final ClassValidator<JPAValidateListener> NO_VALIDATOR;
static {
validators = new WeakHashMap<Class, WeakReference<ClassValidator>>();
NO_VALIDATOR = new ClassValidator<JPAValidateListener>( JPAValidateListener.class);
}
//keep hardref at the instance level
private final Set<ClassValidator> currentValidators = new HashSet<ClassValidator>();
@PrePersist
@PreUpdate
@SuppressWarnings( "unchecked" )
public void onChange(Object object) {
if (object == null) return;
Class entity = object.getClass();
WeakReference<ClassValidator> weakValidator = validators.get(entity);
ClassValidator validator = weakValidator != null ? weakValidator.get() : null;
if ( validator == null ) {
//initialize
//TODO reuse the same reflection manager?
validator = new ClassValidator(entity);
if ( ! validator.hasValidationRules() ) {
validator = NO_VALIDATOR;
}
validators.put( entity, new WeakReference<ClassValidator>(validator) );
currentValidators.add( validator );
}
if ( validator != NO_VALIDATOR ) {
validator.assertValid( object );
}
}
}