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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

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

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * 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).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package javax.xml.bind.annotation;

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

import java.lang.annotation.Retention;

import java.lang.annotation.Target;

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

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

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

/**

 * Maps a JavaBean property to a XML element derived from property name.

 *

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

 * <p>

 * <tt>@XmlElement</tt> annotation can be used with the following program

 * elements:

 * <ul>

 *   <li> a JavaBean property </li>

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

 *   <li> within {@link XmlElements}

 * <p>

 *

 * </ul>

 *

 * The usage is subject to the following constraints:

 * <ul>

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

 *            {@link XmlID},

 *            {@link XmlIDREF},

 *            {@link XmlList},

 *            {@link XmlSchemaType},

 *            {@link XmlValue},

 *            {@link XmlAttachmentRef},

 *            {@link XmlMimeType},

 *            {@link XmlInlineBinaryData},

 *            {@link XmlElementWrapper},

 *            {@link XmlJavaTypeAdapter}</li>

 *   <li> if the type of JavaBean property is a collection type of

 *        array, an indexed property, or a parameterized list, and

 *        this annotation is used with {@link XmlElements} then,

 *        <tt>@XmlElement.type()</tt> must be DEFAULT.class since the

 *        collection item type is already known. </li>

 * </ul>

 *

 * <p>

 * A JavaBean property, when annotated with @XmlElement annotation

 * is mapped to a local element in the XML Schema complex type to

 * which the containing class is mapped.

 *

 * <p>

 * <b>Example 1: </b> Map a public non static non final field to local

 * element

 * <pre>

 *     //Example: Code fragment

 *     public class USPrice {

 *         @XmlElement(name="itemprice")

 *         public java.math.BigDecimal price;

 *     }

 *

 * <p>

 *

 * <b> Example 2: </b> Map a field to a nillable element.

 *   <pre>

 *

 *     //Example: Code fragment

 *     public class USPrice {

 *         @XmlElement(nillable=true)

 *         public java.math.BigDecimal price;

 *     }

 *

 * <p>

 * <b> Example 3: </b> Map a field to a nillable, required element.

 *   <pre>

 *

 *     //Example: Code fragment

 *     public class USPrice {

 *         @XmlElement(nillable=true, required=true)

 *         public java.math.BigDecimal price;

 *     }

 *

 *

 * <p> <b>Example 4: </b>Map a JavaBean property to an XML element

 * with anonymous type.</p>

 * <p>

 * See Example 6 in @{@link XmlType}.

 *

 * <p>

 * @author Sekhar Vajjhala, Sun Microsystems, Inc.

 * @since 1.6, JAXB 2.0

 */

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

public @interface XmlElement {

    /**

     * Name of the XML Schema element.

     * <p> If the value is "##default", then element name is derived from the

     * JavaBean property name.

     */

    String name() default "##default";

    /**

     * Customize the element declaration to be nillable.

     * <p>If nillable() is true, then the JavaBean property is

     * mapped to a XML Schema nillable element declaration.

     */

    boolean nillable() default false;

    /**

     * Customize the element declaration to be required.

     * <p>If required() is true, then Javabean property is mapped to

     * an XML schema element declaration with minOccurs="1".

     * maxOccurs is "1" for a single valued property and "unbounded"

     * for a multivalued property.

     * <p>If required() is false, then the Javabean property is mapped

     * to XML Schema element declaration with minOccurs="0".

     * maxOccurs is "1" for a single valued property and "unbounded"

     * for a multivalued property.

     */

    boolean required() default false;

    /**

     * XML target namespace of the XML Schema 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>

     *  namespace.

     * </ol>

     */

    String namespace() default "##default";

    /**

     * Default value of this element.

     *

     * <p>

     * The <pre>'\u0000'</pre> value specified as a default of this annotation element

     * is used as a poor-man's substitute for null to allow implementations

     * to recognize the 'no default value' state.

     */

    String defaultValue() default "\u0000";

    /**

     * The Java class being referenced.

     */

    Class type() default DEFAULT.class;

    /**

     * Used in {@link XmlElement#type()} to

     * signal that the type be inferred from the signature

     * of the property.

     */

    static final class DEFAULT {}

}