Maven Jaxb插件implClass绑定不起作用

Question

我有一个由jaxb2-maven-plugin使用XML schema生成的Task类。 这是模式：

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
           targetNamespace="http://www.w3schools.com"
           jaxb:version="2.1">
  <xs:element name="experiment">
    <xs:complexType>
      <xs:sequence>
        <xs:element type="xs:string" name="name"/>
        <xs:element name="globalVars">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="var" maxOccurs="unbounded" minOccurs="0">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element type="xs:string" name="name"/>
                    <xs:element type="xs:string" name="value"/>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
        <xs:element name="tasks">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="task" maxOccurs="unbounded" minOccurs="0">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element type="xs:string" name="id"/>
                    <xs:element type="xs:string" name="command"/>
                    <xs:element name="dependencies" minOccurs="0">
                      <xs:complexType>
                        <xs:sequence>
                          <xs:element type="xs:string" name="dependency" maxOccurs="unbounded"
                                      minOccurs="0"/>
                        </xs:sequence>
                      </xs:complexType>
                    </xs:element>
                    <xs:element name="requirements" minOccurs="0">
                      <xs:complexType>
                        <xs:sequence>
                          <xs:element type="xs:string" name="ram"/>
                          <xs:element type="xs:byte" name="cores"/>
                          <xs:element type="xs:string" name="storage"/>
                          <xs:element type="xs:string" name="timeout"/>
                        </xs:sequence>
                      </xs:complexType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

以及生成的Task类：

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = {
    "id",
    "command",
    "dependencies",
    "requirements"
})
@Generated(value = "com.sun.tools.xjc.Driver", date = "2018-11-03T03:54:10-03:00", comments = "JAXB RI v2.3.0")
public class Task {

    @XmlElement(required = true)
    @Generated(value = "com.sun.tools.xjc.Driver", date = "2018-11-03T03:54:10-03:00", comments = "JAXB RI v2.3.0")
    protected String id;
    @XmlElement(required = true)
    @Generated(value = "com.sun.tools.xjc.Driver", date = "2018-11-03T03:54:10-03:00", comments = "JAXB RI v2.3.0")
    protected String command;
    @Generated(value = "com.sun.tools.xjc.Driver", date = "2018-11-03T03:54:10-03:00", comments = "JAXB RI v2.3.0")
    @XmlElementWrapper
    @XmlElement(name = "dependency", namespace = "http://www.w3schools.com")
    protected List<String> dependencies = new ArrayList<String>();
    @Generated(value = "com.sun.tools.xjc.Driver", date = "2018-11-03T03:54:10-03:00", comments = "JAXB RI v2.3.0")
    protected Requirements requirements;

    // Some getters & setters

}

我想向该Task类添加一个方法，所以我搜索了一个解决方案并找到了这篇帖子Adding extra methods to a JAXB class generated from schema。

因此，我创建了一个TaskNode类作为子类，并为XML绑定文件添加了自定义项：

TaskNode：

public class TaskNode extends Task {
    public void doSomething() {
      // ...
    }
}

XML绑定：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<jaxb:bindings
        xmlns:xs="http://www.w3.org/2001/XMLSchema"
        xmlns:jaxb="http://java.sun.com/xml/ns/jaxb"
        version="2.1">
  <!-- The customization -->
  <jaxb:bindings schemaLocation="../schema/experiment.xsd" node="/descendant::xs:element[@name='task']">
    <jaxb:class implClass="br.ufop.decom.TaskNode"/>
  </jaxb:bindings>
  <!-- Generate a class for all xml element instead a single class for everything -->
  <jaxb:globalBindings localScoping="toplevel"/>
</jaxb:bindings>

但是此解决方案给了我这个错误：

[ERROR] file:/D:/IntelliJ%20Projects/Experimentor/src/main/resources/bindings/experiment.xjb [7,53] 
org.xml.sax.SAXParseException; systemId: file:/D:/IntelliJ%20Projects/Experimentor/src/main/resources/bindings/experiment.xjb; lineNumber: 7; columnNumber: 53; A class/interface with the same name "br.ufop.decom.Task" is already in use. Use a class customization to resolve this conflict.

如何解决此错误？

这是我的项目设置pom.xml：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>br.ufop.decom</groupId>
  <artifactId>experimentor</artifactId>
  <version>1.0-SNAPSHOT</version>

  <build>
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
          <configuration>
            <source>1.8</source>
            <target>1.8</target>
          </configuration>
        </plugin>
      </plugins>
    </pluginManagement>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>jaxb2-maven-plugin</artifactId>
        <version>2.4</version>
        <executions>
          <execution>
            <phase>generate-sources</phase>
            <goals>
              <goal>xjc</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <locale>us</locale>
          <sources>
            <source>src/main/resources/schema/experiment.xsd</source>
          </sources>
          <xjbSources>
            <xjbSource>src/main/resources/bindings/experiment.xjb</xjbSource>
          </xjbSources>
          <packageName>br.ufop.decom</packageName>
          <readOnly>true</readOnly>
          <verbose>true</verbose>
          <addGeneratedAnnotation>true</addGeneratedAnnotation>
          <encoding>UTF-8</encoding>
          <extension>true</extension>
          <arguments>
            <argument>-Xxew</argument>
            <argument>-Xfluent-api</argument>
            <argument>-Xjaxbindex</argument>
          </arguments>
        </configuration>
        <dependencies>
          <dependency>
            <groupId>com.github.jaxb-xew-plugin</groupId>
            <artifactId>jaxb-xew-plugin</artifactId>
            <version>1.10</version>
          </dependency>
          <dependency>
            <groupId>net.java.dev.jaxb2-commons</groupId>
            <artifactId>jaxb-fluent-api</artifactId>
            <version>2.1.8</version>
          </dependency>
          <dependency>
            <groupId>org.jvnet.jaxb2_commons</groupId>
            <artifactId>jaxb2-basics</artifactId>
            <version>0.12.0</version>
          </dependency>
        </dependencies>
      </plugin>
    </plugins>
  </build>
</project>