Getting error Caused by: org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class

Question

I am newbie to JPA/Hyperjaxb arena. My goal is to generate a many-to-many mapping between Author and Book tables (postgres database).

In the database- Author table has columns - id, name and Book table has columns - id, title. I have a junction (linking) table AUTHORS_BOOKS that has columns aid, bid (where aid maps to id field in the Author table and bid maps to id field in the Book table).

We are exposing a webservice (lets not focus on why a webservice) to allow clients to query/crud on Authors and Books. For the webservice I am creating pojos using hyperjaxb notations (again thats just how its been).

Here is my types.xsd file:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

<xs:complexType name="author">
    <xs:sequence>
        <xs:element name="id" type="xs:long"/>
        <xs:element name="name" type="xs:string" />
        <xs:element name="books" type="tns:book" minOccurs="0" maxOccurs="1000"/>
    </xs:sequence>
</xs:complexType>

<xs:complexType name="book">
    <xs:sequence>
        <xs:element name="id" type="xs:long"/>
        <xs:element name="title" type="xs:string"/>
        <xs:element name="authors" type="tns:author" minOccurs="0" maxOccurs="1000"/>
    </xs:sequence>
</xs:complexType>

Here is the bindings.xjb file:

<?xml version="1.0" encoding="UTF-8"?>

<jaxb:bindings schemaLocation="sampletypes.xsd"
    node="/xs:schema">
    <jaxb:bindings node="xs:complexType[@name='author']">
        <hj:entity>
            <orm:table name="AUTHORS">
                <orm:unique-constraint>
                    <orm:column-name>NAME</orm:column-name>
                </orm:unique-constraint>
            </orm:table>
        </hj:entity>        
    </jaxb:bindings>

    <jaxb:bindings node="xs:complexType[@name='cocom']">
        <hj:entity>
               <orm:table name="BOOKS">
                     <orm:unique-constraint>
                            <orm:column-name>NAME</orm:column-name>
                     </orm:unique-constraint>
               </orm:table>
        </hj:entity>        
     </jaxb:bindings>

    <jaxb:bindings
            node="xs:complexType[@name='author']//xs:element[@name='books']">
                   <hj:many-to-many name="books">
                         <orm:join-table name="AUTHORS_BOOKS">
                                <orm:join-column name="aid" referenced-column-name="ID" />
                                <orm:inverse-join-column name="bid" referenced-column-name="ID" />
                         </orm:join-table>
                   </hj:many-to-many>
     </jaxb:bindings>

     <jaxb:bindings
                node="xs:complexType[@name='book']//xs:element[@name='authors']">
                       <hj:many-to-many name="authors" mappedBy="books">
                       <hj:cascade>
                       <hj:cascade-persist/>
                       </hj:cascade>
                       </hj:many-to-many>
      </jaxb:bindings>

    <jaxb:bindings
        node="xs:complexType[@name='author']//xs:element[@name='id']">
        <hj:id>
            <orm:generated-value strategy="AUTO" />
        </hj:id>
    </jaxb:bindings>

    <jaxb:bindings
        node="xs:complexType[@name='book']//xs:element[@name='id']">
        <hj:id>
            <orm:generated-value strategy="AUTO" />
        </hj:id>
    </jaxb:bindings>

</jaxb:bindings>

Here is (part of) the generated Author.java :

 @XmlAccessorType(XmlAccessType.FIELD)
 @XmlType(name = "author", propOrder = {
"id",
"name",
"books"
})
@Entity(name = "Author")
@Table(name = "AUTHOR", uniqueConstraints = {
@UniqueConstraint(columnNames = {
    "NAME"
})
})
 @Inheritance(strategy = InheritanceType.JOINED)
 public class Author
implements Serializable, Equals, HashCode, ToString
{

 //some othe stuff

@ManyToMany(targetEntity = Book.class, cascade = {
    CascadeType.ALL
})
@JoinTable(name = "AUTHORS_BOOKS", joinColumns = {
    @JoinColumn(name = "aid", referencedColumnName = "ID")
}, inverseJoinColumns = {
    @JoinColumn(name = "bid", referencedColumnName = "ID")
})
public List<Book> getBooks() {
    if (books == null) {
        books = new ArrayList<Book>();
    }
    return this.books;
}

}

Here is (part of) the generate Book.java:

 @XmlAccessorType(XmlAccessType.FIELD)
 @XmlType(name = "book", propOrder = {
"id",
"title",
"authors"
})
@Entity(name = "Book")
@Table(name = "BOOK", uniqueConstraints = {
@UniqueConstraint(columnNames = {
    "NAME"
})
})

@Inheritance(strategy = InheritanceType.JOINED)
public class Book
implements Serializable, Equals, HashCode, ToString
{

private final static long serialVersionUID = 1L;
protected long id;
@XmlElement(required = true)
protected String title;
protected List<Author> authors;

/**
 * Gets the value of the id property.
 * 
 */
@Id
@Column(name = "ID", scale = 0)
@GeneratedValue(strategy = GenerationType.AUTO)
public long getId() {
    return id;
}

/**
 * Sets the value of the id property.
 * 
 */
public void setId(long value) {
    this.id = value;
}

@Basic
@Column(name = "NAME_", length = 255)
public String getName() {
    return name;
}

public void setName(String value) {
    this.name = value;
}

@ManyToMany(targetEntity = Book.class, cascade = {
    CascadeType.ALL
})
@JoinTable(name = "AUTHORS_BOOKS", joinColumns = {
    @JoinColumn(name = "PARENT_AUTHOR_ID")
}, inverseJoinColumns = {
    @JoinColumn(name = "CHILD_BOOK_ID")
})
public List<Book> getBooks() {
    if (books == null) {
        books = new ArrayList<Book>();
    }
    return this.books;
}

I am not sure what I am doing wrong but I get the following error when I deploy the war file to tomcat (7.0.34, also tried couple other 7.0.x versions)

Error Message: 
Caused by: org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class:com.mycompany.Author.books[com.mycompany.Book]

I been searching the web for answers and either there are no solutions or most errors were due to lack of @Entity or @Id or targetEntity field in @ManyToMany tag. I could really use some pointers on this! Really appreciate your time and help! Thanks.

Answer 1

Thank you all for help! Turns out it was a mapping problem. In the /src/main/resources/persistence.xml file I forgot to add the full class path (for Book.java) so Hibernate couldn't find it. So this was more of an integration issue. Thank you again for help!

Answer 2

The question is, why does Hibernate think that com.mycompany.Book is unmapped.

I would suspect a problem with duplicate classes or something like that. Try running an isolated roundtrip test first (HJ3 provides some support for that). This has clearly nothing to do with Tomcat version and so on.

Answer 3

Had the same. TUrns out I was stupid enough to write List in the oneToMany class instead of List...