org.hibernate.MappingException: Could not determine type for Set / List

I was simplifying the domain model of a pet project by removing an unneccesarry entity by using JPA 2.0's ElementCollection annotation:

public class SecurityDetail {

public enum AuthorityRole{
  ROLE_ADMIN,
  ROLE_SUPER,
  ROLE_USER
}
....
@ElementCollection
@CollectionTable(
  name="Authority",
  joinColumns=@JoinColumn(name="username")
)
private Set authorities;
....

However I was getting this error message:
org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: SecurityDetail, for columns: [org.hibernate.mapping.Column(authorities)]


Digging around (googling) I ended up on this blog entry: blog.m1key.me/2010/06/orghibernatemappingexception-could-not.html, which main solution is to make sure you have a newer hibernate, version 3.5.3 or later.


I use maven, with the hibernate3-maven-plugin, sql-maven-plugin and dbunit-maven-plugin to create the schema, database and to populate data. So I bumped the org.hibernate:hibernate-entitymanager dependency from 3.5.0 to 3.5.3-Final. (and fixed my own nexus repository to pull JBoss's latest jars.)

However it did not fix the problem. But by reading the comments of the blog entry above I also realised that my hibernate3-maven-plugin may be using older dependencies. So I explicitly added the recent verions of org.hibernate:hibernate-core dependency to both the plugin and the app, as well as org.hibernate:hibernate-entitymanager to the plugin as well:

<properties>
  <hibernate.version>3.5.3-Final</hibernate.version>
</properties>
....
<dependencies>
  <dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-entitymanager</artifactId>
    <version>${hibernate.version}</version>
    <exclusions>
      <exclusion>
        <groupId>cglib</groupId>
        <artifactId>cglib</artifactId>
      </exclusion>
      <exclusion>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
      </exclusion>
    </exclusions>
  </dependency>
  <dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>${hibernate.version}</version>
    <exclusions>
      <exclusion>
        <groupId>cglib</groupId>
        <artifactId>cglib</artifactId>
      </exclusion>
      <exclusion>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
      </exclusion>
    </exclusions>
  </dependency>
</dependencies>
....
<plugins>
  <plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>hibernate3-maven-plugin</artifactId>
    <version>2.2</version>
    <executions>
      <execution>
        <phase>process-classes</phase>
        <goals>
          <goal>hbm2ddl</goal>
        </goals>
      </execution>
    </executions>
    <configuration>
      <components>
        <component>
          <name>hbm2ddl</name>
          <implementation>jpaconfiguration</implementation>
        </component>
      </components>
      <componentProperties>
        <persistenceunit>${project.artifactId}</persistenceunit>
        <outputfilename>schema.ddl</outputfilename>
        <drop>false</drop>
        <create>true</create>
        <export>false</export>
        <format>true</format>
      </componentProperties>
    </configuration>
    <dependencies>
      <dependency>
        <groupId>hsqldb</groupId>
        <artifactId>hsqldb</artifactId>
        <version>${hsqldb.version}</version>
      </dependency>
      <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>${hibernate.version}</version>
        <exclusions>
          <exclusion>
            <groupId>cglib</groupId>
            <artifactId>cglib</artifactId>
          </exclusion>
          <exclusion>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
          </exclusion>
        </exclusions>
      </dependency>
      <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>${hibernate.version}</version>
        <exclusions>
          <exclusion>
            <groupId>cglib</groupId>
            <artifactId>cglib</artifactId>
          </exclusion>
          <exclusion>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
          </exclusion>
        </exclusions>
      </dependency>
    </dependencies>
  </plugin>
</plugins>