jakarta.xml.bind/jakarta.xml.bind-api/3.0.0 : jakarta/xml/bind/annotation/XmlAnyElement.java

XmlAnyElement
- lax(): boolean
- value(): Class<DomHandler>
https://github.com/eclipse-ee4j/jaxb-api/jakarta.xml.bind-api: Jakarta XML Binding API (Eclipse Foundation)
Eclipse Distribution License - v 1.0
Roman Grigoriadi (Oracle Corporation)
/*
 * Copyright (c) 2005, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0, which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package jakarta.xml.bind.annotation;

import org.w3c.dom.Element;

import jakarta.xml.bind.JAXBContext;
import jakarta.xml.bind.JAXBElement;
import jakarta.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import java.util.List;

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

Maps a JavaBean property to XML infoset representation and/or JAXBElement.

This annotation serves as a "catch-all" property while unmarshalling
xml content into a instance of a Jakarta XML Binding annotated class. It typically
annotates a multi-valued JavaBean property, but it can occur on
single value JavaBean property. During unmarshalling, each xml element
that does not match a static @XmlElement or @XmlElementRef
annotation for the other JavaBean properties on the class, is added to this
"catch-all" property.
Usages:
@XmlAnyElement public Element[] others; // Collection of Element or JAXBElements. @XmlAnyElement(lax="true") public Object[] others; @XmlAnyElement private List<Element> nodes; @XmlAnyElement private Element node; 
Restriction usage constraints
 This annotation is mutually exclusive with XmlElement, XmlAttribute, XmlValue, XmlElements, XmlID, and XmlIDREF. 
 There can be only one XmlAnyElement annotated JavaBean property in a class and its super classes. 
Relationship to other annotations
 This annotation can be used with XmlJavaTypeAdapter, so that users can map their own data structure to DOM, which in turn can be composed into XML. 
 This annotation can be used with XmlMixed like this: 
// List of java.lang.String or DOM nodes.
@XmlAnyElement @XmlMixed
List<Object> others;

Schema To Java example
The following schema would produce the following Java class:

<xs:complexType name="foo">
  <xs:sequence>
    <xs:element name="a" type="xs:int" />
    <xs:element name="b" type="xs:int" />
    <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded" />
  </xs:sequence>
</xs:complexType>

class Foo { int a; int b; @XmlAnyElement List<Element> any; } 
It can unmarshal instances like

<foo xmlns:e="extra">
  <a>1</a>
  <e:other />  // this will be bound to DOM, because unmarshalling is orderless
  <b>3</b>
  <e:other />
  <c>5</c>     // this will be bound to DOM, because the annotation doesn't remember namespaces.
</foo>

The following schema would produce the following Java class:

<xs:complexType name="bar">
  <xs:complexContent>
  <xs:extension base="foo">
    <xs:sequence>
      <xs:element name="c" type="xs:int" />
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded" />
    </xs:sequence>
  </xs:extension>
</xs:complexType>

class Bar extends Foo {
  int c;
  // Foo.getAny() also represents wildcard content for type definition bar.
}

It can unmarshal instances like

<bar xmlns:e="extra">
  <a>1</a>
  <e:other />  // this will be bound to DOM, because unmarshalling is orderless
  <b>3</b>
  <e:other />
  <c>5</c>     // this now goes to Bar.c
  <e:other />  // this will go to Foo.any
</bar>

Using XmlAnyElement with XmlElementRef
 The XmlAnyElement annotation can be used with XmlElementRefs to designate additional elements that can participate in the content tree. 

The following schema would produce the following Java class:

<xs:complexType name="foo">
  <xs:choice maxOccurs="unbounded" minOccurs="0">
    <xs:element name="a" type="xs:int" />
    <xs:element name="b" type="xs:int" />
    <xs:any namespace="##other" processContents="lax" />
  </xs:choice>
</xs:complexType>

class Foo { @XmlAnyElement(lax="true") @XmlElementRefs({ @XmlElementRef(name="a", type="JAXBElement.class") @XmlElementRef(name="b", type="JAXBElement.class") }) List<Object> others; } @XmlRegistry class ObjectFactory { ... @XmlElementDecl(name = "a", namespace = "", scope = Foo.class) JAXBElement<Integer> createFooA( Integer i ) { ... } @XmlElementDecl(name = "b", namespace = "", scope = Foo.class) JAXBElement<Integer> createFooB( Integer i ) { ... } 
It can unmarshal instances like
<foo xmlns:e="extra">   <a>1</a> // this will unmarshal to a JAXBElement instance whose value is 1.   <e:other /> // this will unmarshal to a DOM Element.   <b>3</b> // this will unmarshal to a JAXBElement instance whose value is 1. </foo> 
W3C XML Schema "lax" wildcard emulation
The lax element of the annotation enables the emulation of the "lax" wildcard semantics.
For example, when the Java source code is annotated like this:
@XmlRootElement class Foo { @XmlAnyElement(lax=true) public Object[] others; } 
then the following document will unmarshal like this:

<foo>
  <unknown />
  <foo />
</foo>
Foo foo = unmarshal();
// 1 for 'unknown', another for 'foo'
assert foo.others.length==2;
// 'unknown' unmarshals to a DOM element
assert foo.others[0] instanceof Element;
// because of lax=true, the 'foo' element eagerly
// unmarshals to a Foo object.
assert foo.others[1] instanceof Foo;

Author: Kohsuke Kawaguchi
Since: 1.6, JAXB 2.0/**
 * Maps a JavaBean property to XML infoset representation and/or JAXBElement.
 *
 * <p>
 * This annotation serves as a "catch-all" property while unmarshalling
 * xml content into a instance of a Jakarta XML Binding annotated class. It typically
 * annotates a multi-valued JavaBean property, but it can occur on
 * single value JavaBean property. During unmarshalling, each xml element
 * that does not match a static &#64;XmlElement or &#64;XmlElementRef
 * annotation for the other JavaBean properties on the class, is added to this
 * "catch-all" property.
 *
 * <h2>Usages:</h2>
 * <pre>
 * &#64;XmlAnyElement
 * public {@link Element}[] others;
 *
 * // Collection of {@link Element} or JAXBElements.
 * &#64;XmlAnyElement(lax="true")
 * public {@link Object}[] others;
 *
 * &#64;XmlAnyElement
 * private List&lt;{@link Element}&gt; nodes;
 *
 * &#64;XmlAnyElement
 * private {@link Element} node;
 * </pre>
 *
 * <h2>Restriction usage constraints</h2>
 * <p>
 * This annotation is mutually exclusive with
 * {@link XmlElement}, {@link XmlAttribute}, {@link XmlValue},
 * {@link XmlElements}, {@link XmlID}, and {@link XmlIDREF}.
 *
 * <p>
 * There can be only one {@link XmlAnyElement} annotated JavaBean property
 * in a class and its super classes.
 *
 * <h2>Relationship to other annotations</h2>
 * <p>
 * This annotation can be used with {@link XmlJavaTypeAdapter}, so that users
 * can map their own data structure to DOM, which in turn can be composed
 * into XML.
 *
 * <p>
 * This annotation can be used with {@link XmlMixed} like this:
 * <pre>
 * // List of java.lang.String or DOM nodes.
 * &#64;XmlAnyElement &#64;XmlMixed
 * List&lt;Object&gt; others;
 * </pre>
 *
 *
 * <h2>Schema To Java example</h2>
 *
 * The following schema would produce the following Java class:
 * <pre>{@code
 * <xs:complexType name="foo">
 *   <xs:sequence>
 *     <xs:element name="a" type="xs:int" />
 *     <xs:element name="b" type="xs:int" />
 *     <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded" />
 *   </xs:sequence>
 * </xs:complexType>
 * }</pre>
 *
 * <pre>
 * class Foo {
 *   int a;
 *   int b;
 *   &#64;{@link XmlAnyElement}
 *   List&lt;Element&gt; any;
 * }
 * </pre>
 *
 * It can unmarshal instances like
 *
 * <pre>{@code
 * <foo xmlns:e="extra">
 *   <a>1</a>
 *   <e:other />  // this will be bound to DOM, because unmarshalling is orderless
 *   <b>3</b>
 *   <e:other />
 *   <c>5</c>     // this will be bound to DOM, because the annotation doesn't remember namespaces.
 * </foo>
 * }</pre>
 *
 *
 *
 * The following schema would produce the following Java class:
 * <pre>{@code
 * <xs:complexType name="bar">
 *   <xs:complexContent>
 *   <xs:extension base="foo">
 *     <xs:sequence>
 *       <xs:element name="c" type="xs:int" />
 *       <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded" />
 *     </xs:sequence>
 *   </xs:extension>
 * </xs:complexType>
 * }</pre>
 *
 * <pre>
 * class Bar extends Foo {
 *   int c;
 *   // Foo.getAny() also represents wildcard content for type definition bar.
 * }
 * </pre>
 *
 *
 * It can unmarshal instances like
 *
 * <pre>{@code
 * <bar xmlns:e="extra">
 *   <a>1</a>
 *   <e:other />  // this will be bound to DOM, because unmarshalling is orderless
 *   <b>3</b>
 *   <e:other />
 *   <c>5</c>     // this now goes to Bar.c
 *   <e:other />  // this will go to Foo.any
 * </bar>
 * }</pre>
 *
 *
 *
 *
 * <h2>Using {@link XmlAnyElement} with {@link XmlElementRef}</h2>
 * <p>
 * The {@link XmlAnyElement} annotation can be used with {@link XmlElementRef}s to
 * designate additional elements that can participate in the content tree.
 *
 * <p>
 * The following schema would produce the following Java class:
 * <pre>{@code
 * <xs:complexType name="foo">
 *   <xs:choice maxOccurs="unbounded" minOccurs="0">
 *     <xs:element name="a" type="xs:int" />
 *     <xs:element name="b" type="xs:int" />
 *     <xs:any namespace="##other" processContents="lax" />
 *   </xs:choice>
 * </xs:complexType>
 * }</pre>
 *
 * <pre>
 * class Foo {
 *   &#64;{@link XmlAnyElement}(lax="true")
 *   &#64;{@link XmlElementRefs}({
 *     &#64;{@link XmlElementRef}(name="a", type="JAXBElement.class")
 *     &#64;{@link XmlElementRef}(name="b", type="JAXBElement.class")
 *   })
 *   {@link List}&lt;{@link Object}&gt; others;
 * }
 *
 * &#64;XmlRegistry
 * class ObjectFactory {
 *   ...
 *   &#64;XmlElementDecl(name = "a", namespace = "", scope = Foo.class)
 *   {@link JAXBElement}&lt;Integer&gt; createFooA( Integer i ) { ... }
 *
 *   &#64;XmlElementDecl(name = "b", namespace = "", scope = Foo.class)
 *   {@link JAXBElement}&lt;Integer&gt; createFooB( Integer i ) { ... }
 * </pre>
 *
 * It can unmarshal instances like
 *
 * <pre>
 *{@code <foo xmlns:e="extra">}
 *{@code   <a>1</a>}     // this will unmarshal to a {@link JAXBElement} instance whose value is 1.
 *{@code   <e:other />}  // this will unmarshal to a DOM {@link Element}.
 *{@code   <b>3</b>}     // this will unmarshal to a {@link JAXBElement} instance whose value is 1.
 *{@code </foo>}
 * </pre>
 *
 *
 *
 *
 * <h2>W3C XML Schema "lax" wildcard emulation</h2>
 * The lax element of the annotation enables the emulation of the "lax" wildcard semantics.
 * For example, when the Java source code is annotated like this:
 * <pre>
 * &#64;{@link XmlRootElement}
 * class Foo {
 *   &#64;XmlAnyElement(lax=true)
 *   public {@link Object}[] others;
 * }
 * </pre>
 * then the following document will unmarshal like this:
 * <pre>{@code
 * <foo>
 *   <unknown />
 *   <foo />
 * </foo>
 *
 * Foo foo = unmarshal();
 * // 1 for 'unknown', another for 'foo'
 * assert foo.others.length==2;
 * // 'unknown' unmarshals to a DOM element
 * assert foo.others[0] instanceof Element;
 * // because of lax=true, the 'foo' element eagerly
 * // unmarshals to a Foo object.
 * assert foo.others[1] instanceof Foo;
 * }</pre>
 *
 * @author Kohsuke Kawaguchi
 * @since 1.6, JAXB 2.0
 */
@Retention(RUNTIME)
@Target({FIELD,METHOD})
public @interface XmlAnyElement {

    Controls the unmarshaller behavior when it sees elements known to the current JAXBContext. 
When false

If false, all the elements that match the property will be unmarshalled
to DOM, and the property will only contain DOM elements.

When true
 If true, when an element matches a property marked with XmlAnyElement is known to JAXBContext (for example, there's a class with XmlRootElement that has the same tag name, or there's XmlElementDecl that has the same tag name), the unmarshaller will eagerly unmarshal this element to the Jakarta XML Binding object, instead of unmarshalling it to DOM. Additionally, if the element is unknown but it has a known xsi:type, the unmarshaller eagerly unmarshals the element to a JAXBElement, with the unknown element name and the JAXBElement value is set to an instance of the Jakarta XML Binding mapping of the known xsi:type. 


As a result, after the unmarshalling, the property can become heterogeneous;
it can have both DOM nodes and some Jakarta XML Binding objects at the same time.

This can be used to emulate the "lax" wildcard semantics of the W3C XML Schema.
/**
     * Controls the unmarshaller behavior when it sees elements
     * known to the current {@link JAXBContext}.
     *
     * <dl>
     * <dt>When false</dt>
     * <dd>
     * If false, all the elements that match the property will be unmarshalled
     * to DOM, and the property will only contain DOM elements.
     * </dd>
     *
     * <dt>When true</dt>
     * <dd>
     * If true, when an element matches a property marked with {@link XmlAnyElement}
     * is known to {@link JAXBContext} (for example, there's a class with
     * {@link XmlRootElement} that has the same tag name, or there's
     * {@link XmlElementDecl} that has the same tag name),
     * the unmarshaller will eagerly unmarshal this element to the Jakarta XML Binding object,
     * instead of unmarshalling it to DOM. Additionally, if the element is
     * unknown but it has a known xsi:type, the unmarshaller eagerly unmarshals
     * the element to a {@link JAXBElement}, with the unknown element name and
     * the JAXBElement value is set to an instance of the Jakarta XML Binding mapping of the
     * known xsi:type.
     * </dd>
     * </dl>
     *
     * <p>
     * As a result, after the unmarshalling, the property can become heterogeneous;
     * it can have both DOM nodes and some Jakarta XML Binding objects at the same time.
     *
     * <p>
     * This can be used to emulate the "lax" wildcard semantics of the W3C XML Schema.
     */
    boolean lax() default false;

    Specifies the DomHandler which is responsible for actually converting XML from/to a DOM-like data structure. /**
     * Specifies the {@link DomHandler} which is responsible for actually
     * converting XML from/to a DOM-like data structure.
     */
    Class<? extends DomHandler> value() default W3CDomHandler.class;
}
/

jakarta.xml.bind/ jakarta.xml.bind-api/ 3.0.0/ jakarta/xml/bind/annotation/XmlAnyElement.java

Usages:

Restriction usage constraints

Relationship to other annotations

Schema To Java example

Using `XmlAnyElement` with `XmlElementRef`

W3C XML Schema "lax" wildcard emulation
