XmlElement (Java EE 5 SDK)

javax.xml.bind.annotation Annotation Type XmlElement

@Retention(value=RUNTIME)
@Target(value={FIELD,METHOD})
public @interface XmlElement

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

Usage

@XmlElement annotation can be used with the following program elements:

• a JavaBean property
• non static, non transient field
• within XmlElements

• This annotation can be used with following annotations: XmlID, XmlIDREF, XmlList, XmlSchemaType, XmlValue, XmlAttachmentRef, XmlMimeType, XmlInlineBinaryData, XmlElementWrapper, XmlJavaTypeAdapter
• 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 XmlElements then, @XmlElement.type() must be DEFAULT.class since the collection item type is already known.

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.

Example 1: Map a public non static non final field to local element

     //Example: Code fragment
     public class USPrice {
         @XmlElement(name="itemprice")
         public java.math.BigDecimal price;
     }

     <!-- Example: Local XML Schema element -->
     <xs:complexType name="USPrice"/>
       <xs:sequence>
         <xs:element name="itemprice" type="xs:decimal" minOccurs="0"/>
       </sequence>
     </xs:complexType>
   

Example 2: Map a field to a nillable element.

     //Example: Code fragment
     public class USPrice {
         @XmlElement(nillable=true)
         public java.math.BigDecimal price;
     }

     <!-- Example: Local XML Schema element -->
     <xs:complexType name="USPrice">
       <xs:sequence>
         <xs:element name="price" type="xs:decimal" nillable="true" minOccurs="0"/>
       </sequence>
     </xs:complexType>
   

Example 3: Map a field to a nillable, required element.

     //Example: Code fragment
     public class USPrice {
         @XmlElement(nillable=true, required=true)
         public java.math.BigDecimal price;
     }

     <!-- Example: Local XML Schema element -->
     <xs:complexType name="USPrice">
       <xs:sequence>
         <xs:element name="price" type="xs:decimal" nillable="true" minOccurs="1"/>
       </sequence>
     </xs:complexType>
   

Example 4: Map a JavaBean property to an XML element with anonymous type.

See Example 6 in @XmlType.

从以下版本开始:

JAXB2.0

版本:

$Revision: 1.19 $

作者:

Sekhar Vajjhala, Sun Microsystems, Inc.

name

public abstract String name

Name of the XML Schema element.

If the value is "##default", then element name is derived from the JavaBean property name.

默认值:

"##default"

nillable

public abstract boolean nillable

Customize the element declaration to be nillable.

If nillable() is true, then the JavaBean property is mapped to a XML Schema nillable element declaration.

默认值:

false

required

public abstract boolean required

Customize the element declaration to be required.

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.

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.

默认值:

false

namespace

public abstract String namespace

XML target namespace of the XML Schema element.

If the value is "##default", then the namespace is determined as follows:

1. If the enclosing package has XmlSchema annotation, and its elementFormDefault is QUALIFIED, then the namespace of the enclosing class.
2. Otherwise "" (which produces unqualified element in the default namespace.

默认值:

"##default"

defaultValue

public abstract String defaultValue

Default value of this element.

The '' 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.

默认值:

"\u0000"

type

public abstract Class type

The Java class being referenced.

默认值:

javax.xml.bind.annotation.XmlElement.DEFAULT.class

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