Java tutorial
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However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.xml.bind.annotation; import java.lang.annotation.Retention; import java.lang.annotation.Target; import static java.lang.annotation.RetentionPolicy.RUNTIME; import static java.lang.annotation.ElementType.TYPE; /** * Maps a class or an enum type to an XML element. * * <p> <b>Usage</b> </p> * <p> * The @XmlRootElement annotation can be used with the following program * elements: * <ul> * <li> a top level class </li> * <li> an enum type </li> * </ul> * * <p>See "Package Specification" in javax.xml.bind.package javadoc for * additional common information.</p> * * <p> * When a top level class or an enum type is annotated with the * @XmlRootElement annotation, then its value is represented * as XML element in an XML document. * * <p> This annotation can be used with the following annotations: * {@link XmlType}, {@link XmlEnum}, {@link XmlAccessorType}, * {@link XmlAccessorOrder}. * </p> * <p> * <b>Example 1: </b> Associate an element with XML Schema type * <pre> * // Example: Code fragment * @XmlRootElement * class Point { * int x; * int y; * Point(int _x,int _y) {x=_x;y=_y;} * } * </pre> * * <pre> * //Example: Code fragment corresponding to XML output * marshal( new Point(3,5), System.out); * </pre> * * <pre>{@code * * <!-- Example: XML output --> * <point> * <x> 3 </x> * <y> 5 </y> * </point> * }</pre> * * The annotation causes an global element declaration to be produced * in the schema. The global element declaration is associated with * the XML schema type to which the class is mapped. * * <pre>{@code * * <!-- Example: XML schema definition --> * <xs:element name="point" type="point"/> * <xs:complexType name="point"> * <xs:sequence> * <xs:element name="x" type="xs:int"/> * <xs:element name="y" type="xs:int"/> * </xs:sequence> * </xs:complexType> * }</pre> * * <p> * * <b>Example 2: Orthogonality to type inheritance </b> * * <p> * An element declaration annotated on a type is not inherited by its * derived types. The following example shows this. * <pre> * // Example: Code fragment * @XmlRootElement * class Point3D extends Point { * int z; * Point3D(int _x,int _y,int _z) {super(_x,_y);z=_z;} * } * * //Example: Code fragment corresponding to XML output * * marshal( new Point3D(3,5,0), System.out ); * {@code * * <!-- Example: XML output --> * <!-- The element name is point3D not point --> * <point3D> * <x>3</x> * <y>5</y> * <z>0</z> * </point3D> * * <!-- Example: XML schema definition --> * <xs:element name="point3D" type="point3D"/> * <xs:complexType name="point3D"> * <xs:complexContent> * <xs:extension base="point"> * <xs:sequence> * <xs:element name="z" type="xs:int"/> * </xs:sequence> * </xs:extension> * </xs:complexContent> * </xs:complexType> * }</pre> * * <b>Example 3: </b> Associate a global element with XML Schema type * to which the class is mapped. * <pre> * //Example: Code fragment * @XmlRootElement(name="PriceElement") * public class USPrice { * @XmlElement * public java.math.BigDecimal price; * } * {@code * * <!-- Example: XML schema definition --> * <xs:element name="PriceElement" type="USPrice"/> * <xs:complexType name="USPrice"> * <xs:sequence> * <xs:element name="price" type="xs:decimal"/> * </sequence> * </xs:complexType> * }</pre> * * @author Sekhar Vajjhala, Sun Microsystems, Inc. * @since 1.6, JAXB 2.0 */ @Retention(RUNTIME) @Target({ TYPE }) public @interface XmlRootElement { /** * namespace name of the XML element. * <p> * If the value is "##default", then the XML namespace name is derived * from the package of the class ( {@link XmlSchema} ). If the * package is unnamed, then the XML namespace is the default empty * namespace. */ String namespace() default "##default"; /** * local name of the XML element. * <p> * If the value is "##default", then the name is derived from the * class name. * */ String name() default "##default"; }