JavaTM Platform, Enterprise Edition, v 5.0
javax.xml.bind.annotation
Annotation Type XmlRootElement
@Retention(value=RUNTIME)
@Target(value=TYPE)
public @interface XmlRootElement
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:
XmlType , XmlEnum , XmlAccessorType ,
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);
3
5
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 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>
- Since:
- JAXB2.0
- Author:
- Sekhar Vajjhala, Sun Microsystems, Inc.
namespace
public abstract String namespace
- namespace name of the XML element.
If the value is "##default", then the XML namespace name is derived
from the package of the class ( XmlSchema ). If the
package is unnamed, then the XML namespace is the default empty
namespace.
- Default:
- "##default"
name
public abstract String name
- local name of the XML element.
If the value is "##default", then the name is derived from the
class name.
- Default:
- "##default"
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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