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 * published by the Free Software Foundation.  Oracle designates this

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 * This code is distributed in the hope that it will be useful, but WITHOUT

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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package javax.xml.bind.annotation;

import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;

import static java.lang.annotation.RetentionPolicy.RUNTIME;

import static java.lang.annotation.ElementType.FIELD;

import static java.lang.annotation.ElementType.METHOD;

import java.lang.annotation.Retention;

import java.lang.annotation.Target;

/**

 * Generates a wrapper element around XML representation.

 *

 * This is primarily intended to be used to produce a wrapper

 * XML element around collections. The annotation therefore supports

 * two forms of serialization shown below.

 *

 * <pre>

 *    //Example: code fragment

 *      int[] names;

 *

 *    // XML Serialization Form 1 (Unwrapped collection)

 *    <names> ... </names>

 *    <names> ... </names>

 *

 *    // XML Serialization Form 2 ( Wrapped collection )

 *    <wrapperElement>

 *       <names> value-of-item </names>

 *       <names> value-of-item </names>

 *       ....

 *    </wrapperElement>

 * </pre>

 *

 * <p> The two serialized XML forms allow a null collection to be

 * represented either by absence or presence of an element with a

 * nillable attribute.

 *

 * <p> <b>Usage</b> </p>

 * <p>

 * The <tt>@XmlElementWrapper</tt> annotation can be used with the

 * following program elements:

 * <ul>

 *   <li> JavaBean property </li>

 *   <li> non static, non transient field </li>

 * </ul>

 *

 * <p>The usage is subject to the following constraints:

 * <ul>

 *   <li> The property must be a collection property </li>

 *   <li> This annotation can be used with the following annotations:

 *            {@link XmlElement},

 *            {@link XmlElements},

 *            {@link XmlElementRef},

 *            {@link XmlElementRefs},

 *            {@link XmlJavaTypeAdapter}.</li>

 * </ul>

 *

 * <p>See "Package Specification" in javax.xml.bind.package javadoc for

 * additional common information.</p>

 *

 * @author <ul><li>Kohsuke Kawaguchi, Sun Microsystems, Inc.</li><li>Sekhar Vajjhala, Sun Microsystems, Inc.</li></ul>

 * @see XmlElement

 * @see XmlElements

 * @see XmlElementRef

 * @see XmlElementRefs

 * @since JAXB2.0

 *

 */

@Retention(RUNTIME) @Target({FIELD, METHOD})

public @interface XmlElementWrapper {

    /**

     * Name of the XML wrapper element. By default, the XML wrapper

     * element name is derived from the JavaBean property name.

     */

    String name() default "##default";

    /**

     * XML target namespace of the XML wrapper element.

     * <p>

     * If the value is "##default", then the namespace is determined

     * as follows:

     * <ol>

     *  <li>

     *  If the enclosing package has {@link XmlSchema} annotation,

     *  and its {@link XmlSchema#elementFormDefault() elementFormDefault}

     *  is {@link XmlNsForm#QUALIFIED QUALIFIED}, then the namespace of

     *  the enclosing class.

     *

     *  <li>

     *  Otherwise "" (which produces unqualified element in the default

     *  namespace.

     * </ol>

     */

    String namespace() default "##default";

    /**

     * If true, the absence of the collection is represented by

     * using <tt>xsi:nil='true'</tt>. Otherwise, it is represented by

     * the absence of the element.

     */

    boolean nillable() default false;

    /**

     * Customize the wrapper element declaration to be required.

     *

     * <p>

     * If required() is true, then the corresponding generated

     * XML schema element declaration will have <tt>minOccurs="1"</tt>,

     * to indicate that the wrapper element is always expected.

     *

     * <p>

     * Note that this only affects the schema generation, and

     * not the unmarshalling or marshalling capability. This is

     * simply a mechanism to let users express their application constraints

     * better.

     *

     * @since JAXB 2.1

     */

    boolean required() default false;

}