org.eclipse.persistence.oxm.annotations.XmlReadTransformer Maven / Gradle / Ivy
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/*
* Copyright (c) 2011, 2020 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 = 2.2 - Initial contribution
package org.eclipse.persistence.oxm.annotations;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import org.eclipse.persistence.mappings.transformers.AttributeTransformer;
/**
* Purpose: XmlReadTransformer is used to allow the user direct access to the XML in order to populate their
* object model. XmlReadTransformer is used in conjunction with XmlWriteTransformers/XmlWriteTransformer to create a customised
* mapping for a specific attribute. XmlReadTransformer specifies the transformer to be invoked on the
* unmarshal.
*
*
Mapping a transformation: A transformer can be configured to perform both the
* XML instance-to-Java attribute transformation at unmarshall time (via attribute transformer) and
* the Java attribute-to-XML instance transformation at marshal time (via field transformer).
*
Example:
*
XML Schema
*
* <?xml version="1.0" encoding="UTF-8"?>
* <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
* <xsd:element name="employee" type="employee-type"/>
* <xsd:complexType name="employee-type">
* <xsd:sequence>
* <xsd:element name="name" type="xsd:string"/>
* <xsd:element name="normal-hours" type="normal-hours-type"/>
* </xsd:sequence>
* </xsd:complexType>
* <xsd:complexType name="normal-hours-type">
* <xsd:sequence>
* <xsd:element name="start-time" type="xsd:string"/>
* <xsd:element name="end-time" type="xsd:string"/>
* </xsd:sequence>
* </xsd:complexType>
* </xsd:schema>
*
*
*
Employee Class
*
*
* @XmlRootElement(name="employee")
* public class Employee {
* public String name;
* @XmlReadTransformer(transformerClass = NormalHoursTransformer.class)
* @XmlWriteTransformers({
* @XmlWriteTransformer(transformerClass = StartTimeTransformer.class, xmlPath= "normal-hours/start-time/text()"),
* @XmlWriteTransformer(transformerClass = EndTimeTransformer.class, xmlPath="normal-hours/end-time/text()")
* })
* public String[] normalHours;
* }
*
*
* Normal Hours Transformer
*
* public class NormalHoursTransformer implements AttributeTransformer {
* public String[] buildAttributeValue(Record record, Object object, Session session) {
* String startTime = (String)record.get("normal-hours/start-time/text()");
* String endTime = (String)record.get("normal-hours/end-time/text()");
* return new String[]{startTime, endTime};
* }
* public void initialize(AbstractTransformationMapping mapping) {
* }
* }
* }
*
* @see AttributeTransformer
* @see XmlWriteTransformer
* @see XmlWriteTransformers
*/
@Target({METHOD, FIELD})
@Retention(RUNTIME)
public @interface XmlReadTransformer {
/**
* User-defined class that must implement the
* org.eclipse.persistence.mappings.transformers.AttributeTransformer
* interface. The class will be instantiated, its buildAttributeValue will
* be used to create the value to be assigned to the attribute.
* Either transformerClass or method must be specified, but not both.
*/
Class transformerClass() default AttributeTransformer.class;
/**
* The mapped class must have a method with this name which returns a value
* to be assigned to the attribute (not assigns the value to the attribute).
* Either transformerClass or method must be specified, but not both.
*/
String method() default "";
}