jaxb-ri/docs/release-documentation/src/docbook/users-guide-compiling-xml-schema-mapping-of-xs-any.xml

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<section version="5.0" xml:id="compiling-xml-schema-mapping-of-xs-any"
         xml:lang="en" xmlns="http://docbook.org/ns/docbook"
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    <title>Mapping of <literal>&lt;xs:any /&gt;</literal></title>

    <para>XJC binds <literal>&lt;xs:any /&gt;</literal> in the following ways:</para>

    <section xml:id="processContents__skip_">
        <title><literal>processContents="skip"</literal></title>

        <para><literal>&lt;xs:any /&gt;</literal> with <code>processContents=skip</code> means
        any well-formed XML elements can be placed. Therefore, XJC binds this
        to DOM <literal>Element</literal> interface.</para>

        <example>
            <title>Any/Skip schema</title>

            <programlisting language="xml"><![CDATA[<xs:element name="person">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="name" type="xs:string" />
      <xs:any processContents="skip" maxOccurs="unbounded" minOccurs="0" />
    </xs:sequence>
  </xs:complexType>
</xs:element>]]></programlisting>
        </example>

        <example>
            <title>Any/Skip binding</title>

            <programlisting language="java"><![CDATA[import org.w3c.dom.Element;

@XmlRootElement
class Person {
  public String getName();
  public void setName(String);

  @XmlAnyElement
  public List<Element> getAny();
}]]></programlisting>
        </example>
    </section>

    <section xml:id="processContents__strict_">
        <title><literal>processContents="strict"</literal></title>

        <para><literal>&lt;xs:any /&gt;</literal> with <code>processContents=strict</code> (or
        <literal>&lt;xs:any /&gt;</literal> without any processContents attribute, since it
        defaults to "strict") means any XML elements placed here must have
        corresponding schema definitions. This mode is not what people
        typically expect as "<literal>wildcard</literal>", but this is the default. The following
        shows this binding. (<code>lax=true</code> is unintuitive, but it's
        not an error in this document):</para>

        <example>
            <title>Any/Strict schema</title>

            <programlisting language="xml"><![CDATA[<xs:element name="person">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="name" type="xs:string" />
      <xs:any maxOccurs="unbounded" minOccurs="0" />
    </xs:sequence>
  </xs:complexType>
</xs:element>]]></programlisting>
        </example>

        <example>
            <title>Any/Strict binding</title>

            <programlisting language="java"><![CDATA[@XmlRootElement
class Person {
  public String getName();
  public void setName(String);

  @XmlAnyElement(lax=true)
  public List<Object> getAny();
}]]></programlisting>
        </example>

        <para>&binding.spec.name; binds any such element to an <literal>Object</literal>, and
        during unmarshalling, all elements encountered are unmarshalled into
        corresponding &binding.spec.name; objects (including <literal>JAXBElement</literal>s if
        necessary) and placed in this field. If it encounters elements that
        cannot be unmarshalled, DOM elements are produced instead.</para>

        <para>At runtime, you can place either DOM elements or some &binding.spec.name;
        objects that map to elements. A typical mistake is to put a
        <literal>String</literal> that contains XML fragment, but this won't work;
        you'd have to first read that into a DOM.</para>
    </section>

    <section xml:id="processContents__lax_">
        <title><literal>processContents="lax"</literal></title>

        <para><literal>&lt;xs:any /&gt;</literal> with <code>processContents=lax</code> means any
        XML elements can be placed here, but if their element names match
        those defined in the schema, they have to be valid. XJC actually
        handles this exactly like processContents='strict', since the strict
        binding allows unknown elements anyway.</para>
    </section>
</section>