| /* |
| * Copyright (c) 1998, 2021 Oracle and/or its affiliates. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v. 2.0 which is available at |
| * http://www.eclipse.org/legal/epl-2.0, |
| * or the Eclipse Distribution License v. 1.0 which is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause |
| */ |
| |
| // Contributors: |
| // Oracle - initial API and implementation from Oracle TopLink |
| package org.eclipse.persistence.mappings.converters; |
| |
| import java.security.AccessController; |
| import java.security.PrivilegedActionException; |
| |
| import org.eclipse.persistence.exceptions.ConversionException; |
| import org.eclipse.persistence.internal.helper.ClassConstants; |
| import org.eclipse.persistence.internal.security.PrivilegedAccessHelper; |
| import org.eclipse.persistence.internal.security.PrivilegedNewInstanceFromClass; |
| import org.eclipse.persistence.mappings.DatabaseMapping; |
| import org.eclipse.persistence.mappings.foundation.AbstractDirectMapping; |
| import org.eclipse.persistence.sessions.Session; |
| |
| /** |
| * <b>Purpose</b>: Allows a class name to be converted to and from a new instance of the class. |
| * |
| * When using a ClassInstanceConverter, the database will store the Class name and the java object |
| * model will contain an instance of that class initialized with its default constructor |
| * |
| * @author James Sutherland |
| * @since OracleAS TopLink 10<i>g</i> (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. |
| */ |
| @Override |
| public Object convertDataValueToObjectValue(Object fieldValue, Session session) { |
| Object attributeValue = null; |
| if (fieldValue != null) { |
| Class attributeClass = 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. |
| */ |
| @Override |
| public Object convertObjectValueToDataValue(Object attributeValue, Session session) { |
| if (attributeValue == null) { |
| return null; |
| } |
| return attributeValue.getClass().getName(); |
| } |
| |
| /** |
| * INTERNAL: |
| * Set the mapping. |
| */ |
| @Override |
| 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. |
| */ |
| @Override |
| public boolean isMutable() { |
| return false; |
| } |
| } |