为什么 JAXB generateElementProperty=false 没有达到预期的效果？

Question

我正在使用以下绑定文件运行 wsimport 任务：

<jaxb:bindings version="2.1"
               xmlns:jaxb="http://java.sun.com/xml/ns/jaxb" xmlns:xs="http://www.w3.org/2001/XMLSchema" >
    <jaxb:bindings>
        <jaxb:globalBindings generateElementProperty="false" typesafeEnumMaxMembers="2000" />
    </jaxb:bindings>
</jaxb:bindings>

但是，这会导致类使用JAXBElement<String> 而不是String，如下面的getUserSummaryOrTypeOrLogLevel() 所示

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "ConfigSLMAction", propOrder = {
    "userSummaryOrTypeOrLogLevel"
})
public class ConfigSLMAction
    extends ConfigConfigBase
{

    @XmlElementRefs({
        @XmlElementRef(name = "UserSummary", type = JAXBElement.class, required = false),
        @XmlElementRef(name = "LogLevel", type = JAXBElement.class, required = false),
        @XmlElementRef(name = "Type", type = JAXBElement.class, required = false)
    })
    protected List<JAXBElement<String>> userSummaryOrTypeOrLogLevel;
    @XmlAttribute(name = "name")
    protected String name;
    @XmlAttribute(name = "local")
    protected Boolean local;
    @XmlAttribute(name = "intrinsic")
    protected Boolean intrinsic;
    @XmlAttribute(name = "read-only")
    protected Boolean readOnly;
    @XmlAttribute(name = "external")
    protected Boolean external;

    /**
     * Gets the value of the userSummaryOrTypeOrLogLevel property.
     * 
     * <p>
     * This accessor method returns a reference to the live list,
     * not a snapshot. Therefore any modification you make to the
     * returned list will be present inside the JAXB object.
     * This is why there is not a <CODE>set</CODE> method for the userSummaryOrTypeOrLogLevel property.
     * 
     * <p>
     * For example, to add a new item, do as follows:
     * <pre>
     *    getUserSummaryOrTypeOrLogLevel().add(newItem);
     * </pre>
     * 
     * 
     * <p>
     * Objects of the following type(s) are allowed in the list
     * {@link JAXBElement }{@code <}{@link String }{@code >}
     * {@link JAXBElement }{@code <}{@link String }{@code >}
     * {@link JAXBElement }{@code <}{@link String }{@code >}
     * 
     * 
     */
    public List<JAXBElement<String>> getUserSummaryOrTypeOrLogLevel() {
        if (userSummaryOrTypeOrLogLevel == null) {
            userSummaryOrTypeOrLogLevel = new ArrayList<JAXBElement<String>>();
        }
        return this.userSummaryOrTypeOrLogLevel;
    }
    ...
    ...
    ...
}

生成此类的 xsd 文件中的条目如下：

<xsd:complexType name="ConfigSLMAction">
    <xsd:complexContent>
        <xsd:extension base="tns:ConfigConfigBase">
            <xsd:choice maxOccurs="unbounded">
                <xsd:element name="UserSummary" minOccurs="0" maxOccurs="1">
                    <xsd:simpleType>
                        <xsd:union memberTypes="tns:dmString tns:dmEmptyElement" />
                    </xsd:simpleType>
                </xsd:element>
                <xsd:element name="Type" minOccurs="1" maxOccurs="1">
                    <xsd:simpleType>
                        <xsd:union memberTypes="tns:dmSLMActionType tns:dmEmptyElement" />
                    </xsd:simpleType>
                </xsd:element>
                <xsd:element name="LogLevel" minOccurs="0" maxOccurs="1">
                    <xsd:simpleType>
                        <xsd:union memberTypes="tns:dmLogLevel tns:dmEmptyElement" />
                    </xsd:simpleType>
                </xsd:element>
            </xsd:choice>
            <xsd:attributeGroup ref="tns:ConfigAttributes" />
        </xsd:extension>
    </xsd:complexContent>
</xsd:complexType>

这是我的 pom 文件中的 Maven 插件

<plugin>
    <groupId>org.jvnet.jax-ws-commons</groupId>
    <artifactId>jaxws-maven-plugin</artifactId>
    <version>2.3</version>
    <executions>
        <execution>
            <id>wsimport-from-jdk</id>
            <phase>generate-sources</phase>
            <goals>
                <goal>wsimport</goal>
            </goals>
        </execution>
    </executions>
    <configuration>
        <wsdlFiles>
            <wsdlFile>${basedir}/src/main/resources/wsdl/xml-mgmt.wsdl</wsdlFile>
        </wsdlFiles>
        <bindingFiles>
            <bindingFile>${basedir}/src/main/resources/wsdl/bindings.xml</bindingFile>
        </bindingFiles>
        <keep>true</keep>
        <verbose>true</verbose>
        <extension>true</extension>
        <vmArgs>
            <vmArg>-Djavax.xml.accessExternalDTD=all</vmArg>
            <vmArg>-Djavax.xml.accessExternalSchema=all</vmArg>
        </vmArgs>
    </configuration>
</plugin>

谁能解释为什么会这样？ 我希望使用 String 而不是 JAXBElement<String> 并且我在 SO 和其他地方找到的任何内容都表明 generateElementProperty=false 有效，但它不是。

Answer 1

JAXBElement 是强制性的，如果有一个 xsd:choice 可以出现 foo 或 bar 元素并且它们是相同的类型。 一个简单的字符串不足以标记应编组的元素。

如果存在元素nillable="true" 和minOccurs="0"，或者如果有两个具有相同名称xsd:complexType 的全局元素，则也需要JAXBElement。

Answer 2

你可以尝试另一个插件来确保错误在 JAXB 中吗？在我们的项目中，我们正在使用：

        <plugin>
            <groupId>org.apache.cxf</groupId>
            <artifactId>cxf-codegen-plugin</artifactId>
            <executions>
                <execution>
                    <id>generate-sources-ais</id>
                    <phase>generate-sources</phase>
                    <configuration>
                        <defaultOptions>
                            <bindingFiles>
                                <bindingFile>${basedir}/src/main/resources/wsdl/binding/bindings.xml</bindingFile>
                            </bindingFiles>
                        </defaultOptions>
                        <sourceRoot>${project.build.directory}/generated-sources/cxf</sourceRoot>
                        <wsdlRoot>${basedir}/src/main/resources/wsdl</wsdlRoot>
                        <includes>
                            <include>**/*.wsdl</include>
                        </includes>
                    </configuration>
                    <goals>
                        <goal>wsdl2java</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

它会像你期望的那样工作

更新：

你说得对，插件没问题。这是因为选择元素。可能与this重复