Red Hat Summit 红帽全球峰会支持控制台（Console）开发人员开始试用联系人

此内容没有您所选择的语言版本。

37.5. Customizing Fixed Value Attribute Mapping

Overview
复制链接

By default, the code generators map attributes defined as having a fixed value to normal properties. When using schema validation, Apache CXF can enforce the schema definition. However, using schema validation increases message processing time.
Another way to map attributes that have fixed values to Java is to map them to Java constants. You can instruct the code generator to map fixed value attributes to Java constants using the globalBindings customization element. You can also customize the mapping of fixed value attributes to Java constants at a more localized level using the property element.

Global customization
复制链接

You can alter this behavior by adding the globalBinding element's fixedAttributeAsConstantProperty attribute. Setting this attribute to true instructs the code generator to map any attribute defined using fixed attribute to a Java constant.
Example 37.21, “in-Line Customization to Force Generation of Constants” shows an in-line customization that forces the code generator to generate constants for attributes with fixed values.

Example 37.21. in-Line Customization to Force Generation of Constants

<schema targetNamespace="http://widget.com/types/widgetTypes" 
        xmlns="http://www.w3.org/2001/XMLSchema" 
        xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
        xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
        jaxb:version="2.0">
  <annotation>
    <appinfo>
      <jaxb:globalBindings fixedAttributeAsConstantProperty="true" />
    </appinfo>
  </annotation>
  ...
</schema>
Copy to Clipboard Toggle word wrap
Example 37.22, “Binding File to Force Generation of Constants” shows an external binding file that customizes the generation of fixed attributes.

Example 37.22. Binding File to Force Generation of Constants

<jaxb:bindings xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
               xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
               jaxb:version="2.0">
  <jaxb:bindings schemaLocation="types.xsd">
    <jaxb:globalBindings fixedAttributeAsConstantProperty="true" />
  <jaxb:bindings>
<jaxb:bindings>
Copy to Clipboard Toggle word wrap

Local mapping
复制链接

You can customize attribute mapping on a per-attribute basis using the property element's fixedAttributeAsConstantProperty attribute. Setting this attribute to true instructs the code generator to map any attribute defined using fixed attribute to a Java constant.
Example 37.23, “In-Line Customization to Force Generation of Constants” shows an in-line customization that forces the code generator to generate constants for a single attribute with a fixed value.

Example 37.23. In-Line Customization to Force Generation of Constants

<schema targetNamespace="http://widget.com/types/widgetTypes" 
        xmlns="http://www.w3.org/2001/XMLSchema" 
        xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
        xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
        jaxb:version="2.0">
  <complexType name="widgetAttr">
    <sequence>
      ...
    </sequence>
    <attribute name="fixer" type="xsd:int" fixed="7">
      <annotation>
        <appinfo>
          <jaxb:property fixedAttributeAsConstantProperty="true" />
        </appinfo>
      </annotation>
     </attribute>
  </complexType>
  ...
</schema>
Copy to Clipboard Toggle word wrap
Example 37.24, “Binding File to Force Generation of Constants” shows an external binding file that customizes the generation of a fixed attribute.

Example 37.24. Binding File to Force Generation of Constants

<jaxb:bindings xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
               xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
               jaxb:version="2.0">
  <jaxb:bindings schemaLocation="types.xsd">
    <jaxb:bindings node="xsd:complexType[@name='widgetAttr']">
      <jaxb:bindings node="xsd:attribute[@name='fixer']">
            <jaxb:property fixedAttributeAsConstantProperty="true" />
        </jaxb:bindings>
    </jaxb:bindings>
  </jaxb:bindings>
<jaxb:bindings>
Copy to Clipboard Toggle word wrap

Java mapping
复制链接

In the default mapping, all attributes are mapped to standard Java properties with getter and setter methods. When this customization is applied to an attribute defined using the fixed attribute, the attribute is mapped to a Java constant, as shown in Example 37.25, “Mapping of a Fixed Value Attribute to a Java Constant”.

Example 37.25. Mapping of a Fixed Value Attribute to a Java Constant

@XmlAttribute
public final static type NAME = value;
Copy to Clipboard Toggle word wrap
type is determined by mapping the base type of the attribute to a Java type using the mappings described in Section 33.1, “Primitive Types”.
NAME is determined by converting the value of the attribute element's name attribute to all capital letters.
value is determined by the value of the attribute element's fixed attribute.
For example, the attribute defined in Example 37.23, “In-Line Customization to Force Generation of Constants” is mapped as shown in Example 37.26, “Fixed Value Attribute Mapped to a Java Constant”.

Example 37.26. Fixed Value Attribute Mapped to a Java Constant

@XmlRootElement(name = "widgetAttr")
public class WidgetAttr {

    ...

  @XmlAttribute
  public final static int FIXER = 7;

  ...

}
Copy to Clipboard Toggle word wrap
返回顶部
Red Hat logoGithubredditYoutubeTwitter

学习

尝试、购买和销售

社区

关于红帽文档

通过我们的产品和服务，以及可以信赖的内容，帮助红帽用户创新并实现他们的目标。 了解我们当前的更新.

让开源更具包容性

红帽致力于替换我们的代码、文档和 Web 属性中存在问题的语言。欲了解更多详情，请参阅红帽博客.

關於紅帽

我们提供强化的解决方案，使企业能够更轻松地跨平台和环境（从核心数据中心到网络边缘）工作。

Theme

© 2025 Red Hat