java - @RelatedTo(elementClass = Concept.class)RelatedTo.elementClass 必须是类升

Question

阅读本文documentation ，我尝试以这种方式应用到我的代码:

三重

@Entity
@Table(name = "triple")
@NodeEntity
public class TripleDBMoldelNeoImpl implements TripleDBModel{
    protected List<Annotation> annotations;

    @RelatedTo(type = "subject", elementClass = (Class<? extends NodeBacked>) Concept.class) //This is the suggestion Eclipse gives me
    public Concept subject;
    @RelatedTo(type = "object", elementClass = Concept.class)
    public Concept object;
    @RelatedTo(type = "predicate", elementClass = Concept.class)
    public Concept predicate;


    @ManyToMany(
            cascade={CascadeType.ALL }, 
            fetch=FetchType.LAZY
    )   
    @JoinTable(name = "triple_has_annotation", 
            joinColumns={@JoinColumn(name="uri_concept_subject"), @JoinColumn(name="uri_concept_object"), @JoinColumn(name="uri_concept_predicate") },          
            inverseJoinColumns=@JoinColumn(name="annotation_id") )
    public List<Annotation> getAnnotations() {
        return annotations;
    }
    public void setAnnotations(List<Annotation> annotations) {
        this.annotations = annotations;
    }
    @Id 
    @Column(name = "subject", length = 100)
    public Concept getSubject() {
        return subject;
    }
    public void setSubject(Concept subject) {
        this.subject = subject;
    }

    @Id 
    @Column(name = "object", length = 100)
    public Concept getObject() {
        return object;
    }
    public void setObject(Concept object) {
        this.object = object;
    }
    @Id 
    @Column(name = "predicate", length = 100)
    public Concept getPredicate() {
        return predicate;
    }
    public void setPredicate(Concept predicate) {
        this.predicate = predicate;
    }

概念

@NodeEntity(partial = true)
public class ConceptNeoImpl implements java.io.Serializable, Concept {

    private static final long serialVersionUID = 1L;
    private String uri;
    private String label;
    private String ontologyElement;
    private List<Annotation> annotations;
    @RelatedTo(type = "conceptSub", elementClass = TripleDBModel.class)
    private TripleDBModel triple;

    public TripleDBModel getTriple() {
        return triple;
    }

    public void setTriple(TripleDBModel triple) {
        this.triple = triple;
    }

下图解释了我想要的用途

然后，表三元组将使用 neo4j，概念将使用 jpa 和 neo4j。我正在使用 Eclipse IDE 进行编程，它为我提供了纠正错误的建议。第一个是:

@RelatedTo(type = "conceptUriSubject", elementClass = Concept.class)

更正为

@RelatedTo(type = "conceptUriSubject", elementClass = (Class<? extends NodeBacked>) Concept.class)

然后，问题没有解决，并给了我下一条消息

Multiple markers at this line - The value for annotation attribute RelatedTo.elementClass must be a class literal - Type safety: Unchecked cast from Class to Class NodeBacked> - The value for annotation attribute RelatedTo.elementClass must be a class literal - Type safety: Unchecked cast from Class to Class NodeBacked>

有什么想法吗？我对此很陌生，所以我很迷茫，我已经在 Spring 论坛上询问过，但没有成功。提前致谢

编辑 我的 pom.xml

上的插件

<plugins>
          <plugin>
            <!-- Execute the main class -->
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>exec-maven-plugin</artifactId>
            <executions>
              <execution>
                <goals>
                  <goal>exec</goal>
                </goals>
              </execution>
            </executions>
            <configuration>
              <mainClass>org.springframework.data.neo4j.examples.hellograph.App</mainClass>
            </configuration>
          </plugin>
          <plugin>
            <!-- IntelliJ Idea Support -->
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-idea-plugin</artifactId>
            <version>2.2</version>
            <configuration>
              <downloadSources>true</downloadSources>
              <dependenciesAsLibraries>true</dependenciesAsLibraries>
            </configuration>
          </plugin>



            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>aspectj-maven-plugin</artifactId>
                <version>1.0</version>
                <dependencies>
                    <!-- NB: You must use Maven 2.0.9 or above or these are ignored (see 
                        MNG-2972) -->
                    <dependency>
                        <groupId>org.aspectj</groupId>
                        <artifactId>aspectjrt</artifactId>
                        <version>${aspectj.version}</version>
                    </dependency>
                    <dependency>
                        <groupId>org.aspectj</groupId>
                        <artifactId>aspectjtools</artifactId>
                        <version>${aspectj.version}</version>
                    </dependency>
                </dependencies>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>test-compile</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <outxml>true</outxml>
                    <aspectLibraries>
                        <aspectLibrary>
                            <groupId>org.springframework</groupId>
                            <artifactId>spring-aspects</artifactId>
                        </aspectLibrary>
                        <aspectLibrary>
                            <groupId>org.springframework.data</groupId>
                            <artifactId>spring-data-neo4j</artifactId>
                        </aspectLibrary>
                    </aspectLibraries>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>

        </plugins>

eclipse中安装的软件

Answer 1

请使用此更新站点在您的 eclipse IDE 中安装 AspectJ 插件:

http://download.eclipse.org/tools/ajdt/36/dev/update

然后您应该能够使用上下文菜单为您的项目启用 AspectJ 支持。

您的域类将得到增强以实现 NodeBacked 接口(interface)，然后 IDE 不会在注释或其他地方给您任何错误。

抱歉造成困惑。我们将在下一个版本中解决这些问题。

更新:

抱歉，我之前没有注意到这一点，但是您放入 elementClass 中的概念实际上是一个接口(interface)，因为它既没有用 @NodeEntity 注释，也没有扩展 NodeBacked，这才是真正的问题。

我想你在 Spring 也问过这个问题forums ，这是我的建议:

您的 Concept 是一个接口(interface)，目前不扩展 NodeBacked。

一般来说:NodeBacked 接口(interface)被添加到具有 @NodeEntity 注释的类中。

那么您可以尝试相同的解决方案。

• 也可以使用 @NodeEntity 注释 Concept。
• 或者让 Concept 自行扩展 NodeBacked

重要提示: elementClass 应该引用具体实现(这可能适用于接口(interface)，因为它只是用于检查与目标的兼容性)。