javax.xml.bind.annotation.XmlRootElement Maven / Gradle / Ivy
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
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.
*
* Usage
*
* The @XmlRootElement annotation can be used with the following program
* elements:
*
* - a top level class
* - an enum type
*
*
* See "Package Specification" in javax.xml.bind.package javadoc for
* additional common information.
*
*
* 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.
*
*
This annotation can be used with the following annotations:
* {@link XmlType}, {@link XmlEnum}, {@link XmlAccessorType},
* {@link XmlAccessorOrder}.
*
*
* Example 1: Associate an element with XML Schema type
*
* // Example: Code fragment
* @XmlRootElement
* class Point {
* int x;
* int y;
* Point(int _x,int _y) {x=_x;y=_y;}
* }
*
*
*
* //Example: Code fragment corresponding to XML output
* marshal( new Point(3,5), System.out);
*
*
*
* <!-- Example: XML output -->
* <point>
* <x> 3 </x>
* <y> 5 </y>
* </point>
*
*
* 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.
*
*
* <!-- 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>
*
*
*
*
* Example 2: Orthogonality to type inheritance
*
*
* An element declaration annotated on a type is not inherited by its
* derived types. The following example shows this.
*
* // 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 );
*
* <!-- 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>
*
*
* Example 3: Associate a global element with XML Schema type
* to which the class is mapped.
*
* //Example: Code fragment
* @XmlRootElement(name="PriceElement")
* public class USPrice {
* @XmlElement
* public java.math.BigDecimal price;
* }
*
* <!-- 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>
*
*
* @author Sekhar Vajjhala, Sun Microsystems, Inc.
* @since JAXB2.0
*/
@Retention(RUNTIME)
@Target({TYPE})
public @interface XmlRootElement {
/**
* namespace name of the XML element.
*
* 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.
*
* If the value is "##default", then the name is derived from the
* class name.
*
*/
String name() default "##default";
}