oracle.toplink.essentials.mappings.converters.ClassInstanceConverter Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
// Copyright (c) 1998, 2007, Oracle. All rights reserved.
package oracle.toplink.essentials.mappings.converters;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import oracle.toplink.essentials.mappings.*;
import oracle.toplink.essentials.internal.helper.*;
import oracle.toplink.essentials.mappings.foundation.AbstractDirectMapping;
import oracle.toplink.essentials.sessions.*;
import oracle.toplink.essentials.exceptions.*;
import oracle.toplink.essentials.internal.security.PrivilegedAccessHelper;
import oracle.toplink.essentials.internal.security.PrivilegedNewInstanceFromClass;
import oracle.toplink.essentials.internal.sessions.AbstractSession;
/**
* Purpose: Allows a class name to be converter to and from a new instance of the class.
*
* @author James Sutherland
* @since OracleAS TopLink 10g (10.0.3)
*/
public class ClassInstanceConverter implements Converter {
protected DatabaseMapping mapping;
/**
* PUBLIC:
* Default constructor.
*/
public ClassInstanceConverter() {
}
/**
* INTERNAL:
* Convert the class name to a class, then create an instance of the class.
*/
public Object convertDataValueToObjectValue(Object fieldValue, Session session) {
Object attributeValue = null;
if (fieldValue != null) {
Class attributeClass = (Class)((AbstractSession)session).getDatasourcePlatform().convertObject(fieldValue, ClassConstants.CLASS);
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()){
try {
attributeValue = AccessController.doPrivileged(new PrivilegedNewInstanceFromClass(attributeClass));
} catch (PrivilegedActionException exception) {
throw ConversionException.couldNotBeConverted(fieldValue, attributeClass, exception.getException());
}
} else {
attributeValue = PrivilegedAccessHelper.newInstanceFromClass(attributeClass);
}
} catch (Exception exception) {
throw ConversionException.couldNotBeConverted(fieldValue, attributeClass, exception);
}
}
return attributeValue;
}
/**
* INTERNAL:
* Convert to the field class.
*/
public Object convertObjectValueToDataValue(Object attributeValue, Session session) {
if (attributeValue == null) {
return null;
}
return attributeValue.getClass().getName();
}
/**
* INTERNAL:
* Set the mapping.
*/
public void initialize(DatabaseMapping mapping, Session session) {
this.mapping = mapping;
// CR#... Mapping must also have the field classification.
if (getMapping().isDirectToFieldMapping()) {
AbstractDirectMapping directMapping = (AbstractDirectMapping)getMapping();
// Allow user to specify field type to override computed value. (i.e. blob, nchar)
if (directMapping.getFieldClassification() == null) {
directMapping.setFieldClassification(ClassConstants.STRING);
}
}
}
/**
* INTERNAL:
* Return the mapping.
*/
protected DatabaseMapping getMapping() {
return mapping;
}
/**
* INTERNAL:
* If the converter converts the value to a non-atomic value, i.e.
* a value that can have its' parts changed without being replaced,
* then it must return false, serialization can be non-atomic.
*/
public boolean isMutable() {
return false;
}
}