XmlType (Java Platform SE 6) - JDK 5 Documentation v6.0, Java 2 SDK 英文文档

Overview

Package

Class

Use

Tree

Deprecated

Index

Help

Java™ Platform
Standard Ed. 6

PREV CLASS NEXT CLASS

FRAMES NO FRAMES

SUMMARY: REQUIRED | OPTIONAL

DETAIL: ELEMENT

javax.xml.bind.annotation
Annotation Type XmlType

@Retention(value=RUNTIME) @Target(value=TYPE) public @interface XmlType

Maps a class or an enum type to a XML Schema type.

Usage

The @XmlType annnotation 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.

Mapping a Class

A class maps to a XML Schema type. A class is a data container for values represented by properties and fields. A schema type is a data container for values represented by schema components within a schema type's content model (e.g. model groups, attributes etc).

To be mapped, a class must either have a public no-arg constructor or a static no-arg factory method. The static factory method can be specified in factoryMethod() and factoryClass() annotation elements. The static factory method or the no-arg constructor is used during unmarshalling to create an instance of this class. If both are present, the static factory method overrides the no-arg constructor.

A class maps to either a XML Schema complex type or a XML Schema simple type. The XML Schema type is derived based on the mapping of JavaBean properties and fields contained within the class. The schema type to which the class is mapped can either be named or anonymous. A class can be mapped to an anonymous schema type by annotating the class with @XmlType(name="").

Either a global element, local element or a local attribute can be associated with an anonymous type as follows:

global element: A global element of an anonymous type can be derived by annotating the class with @XmlRootElement. See Example 3 below.
local element: A JavaBean property that references a class annotated with @XmlType(name="") and is mapped to the element associated with the anonymous type. See Example 4 below.
attribute: A JavaBean property that references a class annotated with @XmlType(name="") and is mapped to the attribute associated with the anonymous type. See Example 5 below.

Mapping to XML Schema Complex Type

If class is annotated with @XmlType(name="") , it is mapped to an anonymous type otherwise, the class name maps to a complex type name. The XmlName() annotation element can be used to customize the name.
Properties and fields that are mapped to elements are mapped to a content model within a complex type. The annotation element propOrder() can be used to customize the content model to be xs:all or xs:sequence. It is used for specifying the order of XML elements in xs:sequence.
Properties and fields can be mapped to attributes within the complex type.
The targetnamespace of the XML Schema type can be customized using the annotation element namespace().

Mapping class to XML Schema simple type

A class can be mapped to a XML Schema simple type using the @XmlValue annotation. For additional details and examples, see @XmlValue annotation type.

The following table shows the mapping of the class to a XML Schema complex type or simple type. The notational symbols used in the table are:

-> : represents a mapping
[x]+ : one or more occurances of x
[ @XmlValue property ]: JavaBean property annotated with @XmlValue
X : don't care

Target propOrder ClassBody ComplexType SimpleType

Class {} [property]+ -> elements complexcontent
xs:all

Class non empty [property]+ -> elements complexcontent
xs:sequence

Class X no property -> element complexcontent
empty sequence

Class X 1 [ @XmlValue property] &&
[property]+ ->attributes simplecontent

Class X 1 [ @XmlValue property ]&&
no properties -> attribute simpletype

Mapping an enum type

An enum type maps to a XML schema simple type with enumeration facets. The following annotation elements are ignored since they are not meaningful: propOrder() , factoryMethod() , factoryClass() .

Usage with other annotations

This annotation can be used with the following annotations: XmlRootElement, XmlAccessorOrder, XmlAccessorType, XmlEnum. However, XmlAccessorOrder and XmlAccessorType are ignored when this annotation is used on an enum type.

Example 1: Map a class to a complex type with xs:sequence with a customized ordering of JavaBean properties.

   @XmlType(propOrder={"street", "city" , "state", "zip", "name" })
   public class USAddress {
     String getName() {..};
     void setName(String) {..};
 
     String getStreet() {..};
     void setStreet(String) {..};

     String getCity() {..}; 
     void setCity(String) {..};
 
     String getState() {..};
     void setState(String) {..};

     java.math.BigDecimal getZip() {..};
     void setZip(java.math.BigDecimal) {..};
   }

   <!-- XML Schema mapping for USAddress -->
   <xs:complexType name="USAddress">
     <xs:sequence>
       <xs:element name="street" type="xs:string"/>
       <xs:element name="city" type="xs:string"/>
       <xs:element name="state" type="xs:string"/>
       <xs:element name="zip" type="xs:decimal"/>
       <xs:element name="name" type="xs:string"/>
     </xs:all>
   </xs:complexType>

Example 2: Map a class to a complex type with xs:all

 @XmlType(propOrder={})
 public class USAddress { ...}
 
 <!-- XML Schema mapping for USAddress -->
 <xs:complexType name="USAddress">
   <xs:all>
     <xs:element name="name" type="xs:string"/>
     <xs:element name="street" type="xs:string"/>
     <xs:element name="city" type="xs:string"/>
     <xs:element name="state" type="xs:string"/>
     <xs:element name="zip" type="xs:decimal"/>
   </xs:sequence>
 </xs:complexType>

Example 3: Map a class to a global element with an anonymous type.

   @XmlRootElement
   @XmlType(name="")
   public class USAddress { ...}

   <!-- XML Schema mapping for USAddress -->
   <xs:element name="USAddress">
     <xs:complexType>
       <xs:sequence>
         <xs:element name="name" type="xs:string"/>
         <xs:element name="street" type="xs:string"/>
         <xs:element name="city" type="xs:string"/>
         <xs:element name="state" type="xs:string"/>
         <xs:element name="zip" type="xs:decimal"/>
       </xs:sequence>
     </xs:complexType>
   </xs:element>

Example 4: Map a property to a local element with anonmyous type.

   //Example: Code fragment
   public class Invoice {
       USAddress addr;
           ...
       }

   @XmlType(name="")
   public class USAddress { ... }
   } 

   <!-- XML Schema mapping for USAddress -->
   <xs:complexType name="Invoice">
     <xs:sequence>
       <xs:element name="addr">
         <xs:complexType>
           <xs:element name="name", type="xs:string"/>
           <xs:element name="city", type="xs:string"/>
           <xs:element name="city" type="xs:string"/>
           <xs:element name="state" type="xs:string"/>
           <xs:element name="zip" type="xs:decimal"/>
         </xs:complexType>
       ...
     </xs:sequence>
   </xs:complexType>

Example 5: Map a property to an attribute with anonymous type.


     //Example: Code fragment
     public class Item {
         public String name;
         @XmlAttribute 
         public USPrice price;
     }
    
     // map class to anonymous simple type. 
     @XmlType(name="")
     public class USPrice { 
         @XmlValue
         public java.math.BigDecimal price;
     }

     <!-- Example: XML Schema fragment -->
     <xs:complexType name="Item">
       <xs:sequence>
         <xs:element name="name" type="xs:string"/>
         <xs:attribute name="price">
           <xs:simpleType>
             <xs:restriction base="xs:decimal"/>
           </xs:simpleType>
         </xs:attribute>
       </xs:sequence>
     </xs:complexType>

Example 6: Define a factoryClass and factoryMethod

 
      @XmlType(name="USAddressType", factoryClass=USAddressFactory.class,
      factoryMethod="getUSAddress")
      public class USAddress {

          private String city;
          private String name;
          private String state;
          private String street;
          private int    zip;

      public USAddress(String name, String street, String city, 
          String state, int zip) {
          this.name = name;
          this.street = street;
          this.city = city;
          this.state = state;
          this.zip = zip;
      }
  }

  public class USAddressFactory {
      public static USAddress getUSAddress(){
       return new USAddress("Mark Baker", "23 Elm St", 
          "Dayton", "OH", 90952);
  }

Example 7: Define factoryMethod and use the default factoryClass

      @XmlType(name="USAddressType", factoryMethod="getNewInstance")
      public class USAddress {

          private String city;
          private String name;
          private String state;
          private String street;
          private int    zip;

          private USAddress() {}

          public static USAddress getNewInstance(){
              return new USAddress();
          }
      }

Since:: JAXB2.0
See Also:: XmlElement, XmlAttribute, XmlValue, XmlSchema

Optional Element Summary

Class factoryClass
          Class containing a no-arg factory method for creating an instance of this class.

String factoryMethod
          Name of a no-arg factory method in the class specified in factoryClass factoryClass().

String name
          Name of the XML Schema type which the class is mapped.

String namespace
          Name of the target namespace of the XML Schema type.

String[] propOrder
          Specifies the order for XML Schema elements when class is mapped to a XML Schema complex type.

Optional Element Summary
`Class`	`factoryClass` Class containing a no-arg factory method for creating an instance of this class.
`String`	`factoryMethod` Name of a no-arg factory method in the class specified in `factoryClass` factoryClass().
`String`	`name` Name of the XML Schema type which the class is mapped.
`String`	`namespace` Name of the target namespace of the XML Schema type.
`String[]`	`propOrder` Specifies the order for XML Schema elements when class is mapped to a XML Schema complex type.

name

public abstract String name

Name of the XML Schema type which the class is mapped.

Default:: "##default"

propOrder

public abstract String[] propOrder

Specifies the order for XML Schema elements when class is mapped to a XML Schema complex type.

Refer to the table for how the propOrder affects the mapping of class

The propOrder is a list of names of JavaBean properties in the class. Each name in the list is the name of a Java identifier of the JavaBean property. The order in which JavaBean properties are listed is the order of XML Schema elements to which the JavaBean properties are mapped.

All of the JavaBean properties being mapped to XML Schema elements must be listed.

A JavaBean property or field listed in propOrder must not be transient or annotated with @XmlTransient.

The default ordering of JavaBean properties is determined by @XmlAccessorOrder.

Default:: ""

namespace

public abstract String namespace

Name of the target namespace of the XML Schema type. By default, this is the target namespace to which the package containing the class is mapped.

Default:: "##default"

factoryClass

public abstract Class factoryClass

Class containing a no-arg factory method for creating an instance of this class. The default is this class.

If factoryClass is DEFAULT.class and factoryMethod is "", then there is no static factory method.

If factoryClass is DEFAULT.class and factoryMethod is not "", then factoryMethod is the name of a static factory method in this class.

If factoryClass is not DEFAULT.class, then factoryMethod must not be "" and must be the name of a static factory method specified in factoryClass.

Default:: javax.xml.bind.annotation.XmlType.DEFAULT.class

factoryMethod

public abstract String factoryMethod

Name of a no-arg factory method in the class specified in factoryClass factoryClass().

Default:: ""