illegal access to loading collection

Hi

Reading the Hibernate ref. I decided to try a small example, the
weblog.
I am using JBOSS-4.0.4.GA, EJB3 and hibernate-3.2. When I want to
create a new BlogItems object, by adding it to the list of BlogItems,
wich belongs to Blogs entity, I get the

                             illegal access to loading collection

error message.

These are the Java sources:

- the Blogs.java (ENTITY)

package weblog;

import java.util.HashSet;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.UniqueConstraint;

@Entity
@Table(name = "weblog.blogs", uniqueConstraints =
{ @UniqueConstraint(columnNames = { "name" }) })
public class Blogs implements java.io.Serializable {

    private static final long serialVersionUID = 255571063365822285L;
    private int blogId;
    private String name;
    private Set<BlogItems> blogItemses = new HashSet<BlogItems>(0);

    public Blogs() {}

    public Blogs(int blogId) {
        this.blogId = blogId;
    }

    public Blogs(int blogId, String name) {
        this.blogId = blogId;
        this.name = name;
    }

    public Blogs(int blogId, String name, Set<BlogItems> blogItemses) {
        this.blogId = blogId;
        this.name = name;
        this.blogItemses = blogItemses;
    }

    @Id
    @Column(name = "blog_id", unique = true, nullable = false, insertable
= true, updatable = true)
    public int getBlogId() { return this.blogId; }
    public void setBlogId(int blogId) { this.blogId = blogId; }

    @Column(name = "name", unique = true, nullable = false, insertable =
true, updatable = true, length = 50)
    public String getName() { return this.name; }
    public void setName(String name) { this.name = name; }

    @OneToMany(cascade = { CascadeType.ALL }, fetch = FetchType.LAZY,
mappedBy = "blogs")
    public Set<BlogItems> getBlogItemses() { return this.blogItemses; }
    public void setBlogItemses(Set<BlogItems> blogItemses)
{ this.blogItemses = blogItemses; }

    @Override
    public int hashCode() {
        final int PRIME = 31;
        int result = 1;
        result = PRIME * result + blogId;
        result = PRIME * result + ((blogItemses == null) ? 0 :
blogItemses.hashCode());
        result = PRIME * result + ((name == null) ? 0 : name.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        final Blogs other = (Blogs) obj;
        if (blogId != other.blogId)
            return false;
        if (blogItemses == null) {
            if (other.blogItemses != null)
                return false;
        } else if (!blogItemses.equals(other.blogItemses))
            return false;
        if (name == null) {
            if (other.name != null)
                return false;
        } else if (!name.equals(other.name))
            return false;
        return true;
    }

}

- the BlogItems (ENTITY)

package weblog;

import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

@Entity
@Table(name = "weblog.blog_items", uniqueConstraints = {})
public class BlogItems implements java.io.Serializable {

    private static final long serialVersionUID = 288936795343606406L;
    private int blogItemId;
    private Blogs blogs;
    private String title;
    private String text;
    private Date datetime;

    public BlogItems() { }

    public BlogItems(int blogItemId, String title) {
        this.blogItemId = blogItemId;
        this.title = title;
        this.text = title;
        this.datetime = new Date();
    }

    public BlogItems(int blogItemId, Blogs blogs, String title, String
text,
            Date datetime) {
        this.blogItemId = blogItemId;
        this.blogs = blogs;
        this.title = title;
        this.text = text;
        this.datetime = datetime;
    }

    @Id
    @Column(name = "blog_item_id", unique = true, nullable = false,
insertable = true, updatable = true)
    public int getBlogItemId() {
        return this.blogItemId;
    }

    public void setBlogItemId(int blogItemId) {
        this.blogItemId = blogItemId;
    }

    @ManyToOne(cascade = {}, fetch = FetchType.LAZY)
    @JoinColumn(name = "blog", unique = false, nullable = false,
insertable = true, updatable = true)
    public Blogs getBlogs() {
        return this.blogs;
    }

    public void setBlogs(Blogs blogs) {
        this.blogs = blogs;
    }

    @Column(name = "title", unique = false, nullable = false, insertable
= true, updatable = true, length = 50)
    public String getTitle() {
        return this.title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    @Column(name = "text", unique = false, nullable = false, insertable =
true, updatable = true, length = 50)
    public String getText() {
        return this.text;
    }

    public void setText(String text) {
        this.text = text;
    }

    @Temporal(TemporalType.DATE)
    @Column(name = "datetime", unique = false, nullable = false,
insertable = true, updatable = true, length = 4)
    public Date getDatetime() {
        return this.datetime;
    }

    public void setDatetime(Date datetime) {
        this.datetime = datetime;
    }

    @Override
    public int hashCode() {
        final int PRIME = 31;
        int result = 1;
        result = PRIME * result + blogItemId;
        result = PRIME * result + ((blogs == null) ? 0 : blogs.hashCode());
        result = PRIME * result + ((datetime == null) ? 0 :
datetime.hashCode());
        result = PRIME * result + ((text == null) ? 0 : text.hashCode());
        result = PRIME * result + ((title == null) ? 0 : title.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        final BlogItems other = (BlogItems) obj;
        if (blogItemId != other.blogItemId)
            return false;
        if (blogs == null) {
            if (other.blogs != null)
                return false;
        } else if (!blogs.equals(other.blogs))
            return false;
        if (datetime == null) {
            if (other.datetime != null)
                return false;
        } else if (!datetime.equals(other.datetime))
            return false;
        if (text == null) {
            if (other.text != null)
                return false;
        } else if (!text.equals(other.text))
            return false;
        if (title == null) {
            if (other.title != null)
                return false;
        } else if (!title.equals(other.title))
            return false;
        return true;
    }
}

and the STATELESS beans:

package weblog;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

@Stateless
public class BlogsBean implements BlogsRemote, BlogsLocal,
java.io.Serializable {

    private static final long serialVersionUID = 2078312303442351155L;
    private static final Log log = LogFactory.getLog(BlogsBean.class);

    @PersistenceContext(unitName="webloan")
    private EntityManager entityManager;

    public void persist(Blogs transientInstance) {
        log.debug("persisting Blogs instance");
        try {
            entityManager.persist(transientInstance);
            log.debug("persist successful");
        } catch (RuntimeException re) {
            log.error("persist failed", re);
            throw re;
        }
    }

    public void remove(Blogs persistentInstance) {
        log.debug("removing Blogs instance");
        try {
            entityManager.remove(persistentInstance);
            log.debug("remove successful");
        } catch (RuntimeException re) {
            log.error("remove failed", re);
            throw re;
        }
    }

    public Blogs merge(Blogs detachedInstance) {
        log.debug("merging Blogs instance");
        try {
            Blogs result = entityManager.merge(detachedInstance);
            log.debug("merge successful");
            return result;
        } catch (RuntimeException re) {
            log.error("merge failed", re);
            throw re;
        }
    }

    public Blogs findById(int id) {
        log.debug("getting Blogs instance with id: " + id);
        try {
            Blogs instance = entityManager.find(Blogs.class, id);
            log.debug("get successful");
            return instance;
        } catch (RuntimeException re) {
            log.error("get failed", re);
            throw re;
        }
    }

    public void addItem(int blog_id, int blogitem_id, String text) {
        log.debug("1");
        try {
            Blogs instance = entityManager.find(Blogs.class, blog_id);
            BlogItems bi = new BlogItems(blogitem_id, text);
            instance.getBlogItemses().add(bi);
            Blogs result = entityManager.merge(instance);
            log.debug("merge successful");
        } catch (RuntimeException re) {
            log.error("merge failed", re);
            throw re;
        }
    }

}

package gl.weblog;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

@Stateless
public class BlogItemsBean implements BlogItemsRemote, BlogItemsLocal,
java.io.Serializable {

    private static final long serialVersionUID = -6463759247311226709L;
    private static final Log log =
LogFactory.getLog(BlogItemsBean.class);

    @PersistenceContext(unitName="webloan")
    private EntityManager entityManager;

    public void persist(BlogItems transientInstance) {
        log.debug("persisting BlogItems instance");
        try {
            entityManager.persist(transientInstance);
            log.debug("persist successful");
        } catch (RuntimeException re) {
            log.error("persist failed", re);
            throw re;
        }
    }

    public void remove(BlogItems persistentInstance) {
        log.debug("removing BlogItems instance");
        try {
            entityManager.remove(persistentInstance);
            log.debug("remove successful");
        } catch (RuntimeException re) {
            log.error("remove failed", re);
            throw re;
        }
    }

    public BlogItems merge(BlogItems detachedInstance) {
        log.debug("merging BlogItems instance");
        try {
            BlogItems result = entityManager.merge(detachedInstance);
            log.debug("merge successful");
            return result;
        } catch (RuntimeException re) {
            log.error("merge failed", re);
            throw re;
        }
    }

    public BlogItems findById(int id) {
        log.debug("getting BlogItems instance with id: " + id);
        try {
            BlogItems instance = entityManager.find(BlogItems.class, id);
            log.debug("get successful");
            return instance;
        } catch (RuntimeException re) {
            log.error("get failed", re);
            throw re;
        }
    }
}

My client source looks like this:

package weblog;

import java.util.List;
import java.util.Properties;
import javax.naming.InitialContext;

public class Test01 {
    Blogs ablogok;
    BlogItems ablogitemek;

    Test01(String blog_id, String blogitem_id, String blogitem_title) {
        System.out.println("- 0:"+blog_id);
        System.out.println("- 1:"+blogitem_id);
        System.out.println("- 2:"+blogitem_title);
    }

    public void addItemToBlog(String blog_id, String blogitem_id, String
blogitem_title) {
        Integer BLOG_ID = new Integer(blog_id);
        Integer BLOGITEM_ID = new Integer(blogitem_id);
        try {
            Properties properties = new Properties();

properties.put("java.naming.factory.initial","org.jnp.interfaces.NamingContextFactory");

properties.put("java.naming.factory.url.pkgs","=org.jboss.naming:org.jnp.interfaces");
            properties.put("java.naming.provider.url","192.1xx.1xx.1xx:1099");
            InitialContext ctx = new InitialContext();
            BlogsInterface bf = (BlogsInterface) ctx.lookup("BlogsBean/
remote");
            bf.addItem(BLOG_ID.intValue(), BLOGITEM_ID.intValue(),
blogitem_title);
        } catch(Exception ex) {
            System.out.println("ERROR: "+ex.getMessage()+"\n");
            //ex.printStackTrace();
        }
    }

    public static void main(String[] args) {
        Test01 t1 = new Test01(args[0], args[1], args[2]);
        t1.addItemToBlog(args[0], args[1], args[2]);
        t1 = null;
    }
}

and the error stack
Code:

15:27:50,075 ERROR [LazyInitializationException] illegal access to
loading collection
org.hibernate.LazyInitializationException: illegal access to loading
collection
        at
org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollec
tion.java:341)
        at
org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.j
ava:86)
        at
org.hibernate.collection.PersistentSet.hashCode(PersistentSet.java:
355)
        at weblog.Blogs.hashCode(Blogs.java:58)
        at weblog.BlogItems.hashCode(BlogItems.java:101)
        at java.util.HashMap.put(HashMap.java:372)
        at java.util.HashSet.add(HashSet.java:200)
        at java.util.AbstractCollection.addAll(AbstractCollection.java:
238)
        at
org.hibernate.collection.PersistentSet.endRead(PersistentSet.java:273)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.jav
a:183)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.ja
va:268)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.ja
va:249)
        at org.hibernate.loader.Loader.endCollectionLoad(Loader.java:
866)
        at
org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:
853)
        at org.hibernate.loader.Loader.doQuery(Loader.java:717)
        at
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:
224)
        at org.hibernate.loader.Loader.loadCollection(Loader.java:
1919)
        at
org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:
36)
        at
org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollect
ionPersister.java:541)
        at
org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(D
efaultInitializeCollectionEventListener.java:60)
        at
org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:
1705)
        at
org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollec
tion.java:344)
        at
org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.j
ava:86)
        at
org.hibernate.collection.AbstractPersistentCollection.readElementExistence(AbstractPersis
tentCollection.java:142)
        at
org.hibernate.collection.PersistentSet.add(PersistentSet.java:162)
        at weblog.BlogsBean.addItem(BlogsBean.java:69)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:
39)
        at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:
25)
        at java.lang.reflect.Method.invoke(Method.java:589)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
112)
        at
org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:
166)
        at
org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke(EJB3InterceptorsInterceptor
..java:63)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.entity.TransactionScopedEntityManagerInterceptor.invoke(TransactionScopedE
ntityManagerInterceptor.java:54)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOperationsInterceptor.java:
47)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:
79)
        at org.jboss.aspects.tx.TxInterceptor
$Required.invoke(TxInterceptor.java:197)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationInterceptor.java:
76)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.stateless.StatelessInstanceInterceptor.invoke(StatelessInstanceInterceptor
..java:62)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.aspects.security.AuthenticationInterceptor.invoke(AuthenticationInterceptor.jav
a:78)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagationInterceptor.java:
47)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(AsynchronousInterceptor.java:
1
06)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.stateless.StatelessContainer.dynamicInvoke(StatelessContainer.java:
225)
        at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106)
        at
org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invoke(AOPRemotingInvocationHandl
er.java:82)
        at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:
828)
        at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:
681)
        at
org.jboss.remoting.transport.socket.ServerThread.processInvocation(ServerThread.java:
358)
        at
org.jboss.remoting.transport.socket.ServerThread.dorun(ServerThread.java:
398)
        at
org.jboss.remoting.transport.socket.ServerThread.run(ServerThread.java:
239)
15:27:50,081 ERROR [BlogsBean] merge failed
org.hibernate.LazyInitializationException: illegal access to loading
collection
        at
org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollec
tion.java:341)
        at
org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.j
ava:86)
        at
org.hibernate.collection.PersistentSet.hashCode(PersistentSet.java:
355)
        at weblog.Blogs.hashCode(Blogs.java:58)
        at weblog.BlogItems.hashCode(BlogItems.java:101)
        at java.util.HashMap.put(HashMap.java:372)
        at java.util.HashSet.add(HashSet.java:200)
        at java.util.AbstractCollection.addAll(AbstractCollection.java:
238)
        at
org.hibernate.collection.PersistentSet.endRead(PersistentSet.java:273)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.jav
a:183)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.ja
va:268)
        at
org.hibernate.engine.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.ja
va:249)
        at org.hibernate.loader.Loader.endCollectionLoad(Loader.java:
866)
        at
org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:
853)
        at org.hibernate.loader.Loader.doQuery(Loader.java:717)
        at
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:
224)
        at org.hibernate.loader.Loader.loadCollection(Loader.java:
1919)
        at
org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:
36)
        at
org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollect
ionPersister.java:541)
        at
org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(D
efaultInitializeCollectionEventListener.java:60)
        at
org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:
1705)
        at
org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollec
tion.java:344)
        at
org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.j
ava:86)
        at
org.hibernate.collection.AbstractPersistentCollection.readElementExistence(AbstractPersis
tentCollection.java:142)
        at
org.hibernate.collection.PersistentSet.add(PersistentSet.java:162)
        at weblog.BlogsBean.addItem(BlogsBean.java:69)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:
39)
        at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:
25)
        at java.lang.reflect.Method.invoke(Method.java:589)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
112)
        at
org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:
166)
        at
org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke(EJB3InterceptorsInterceptor
..java:63)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.entity.TransactionScopedEntityManagerInterceptor.invoke(TransactionScopedE
ntityManagerInterceptor.java:54)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOperationsInterceptor.java:
47)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:
79)
        at org.jboss.aspects.tx.TxInterceptor
$Required.invoke(TxInterceptor.java:197)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationInterceptor.java:
76)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.stateless.StatelessInstanceInterceptor.invoke(StatelessInstanceInterceptor
..java:62)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.aspects.security.AuthenticationInterceptor.invoke(AuthenticationInterceptor.jav
a:78)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagationInterceptor.java:
47)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(AsynchronousInterceptor.java:
1
06)
        at
org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:
101)
        at
org.jboss.ejb3.stateless.StatelessContainer.dynamicInvoke(StatelessContainer.java:
225)
        at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106)
        at
org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invoke(AOPRemotingInvocationHandl
er.java:82)
        at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:
828)
        at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:
681)
        at
org.jboss.remoting.transport.socket.ServerThread.processInvocation(ServerThread.java:
358)
        at
org.jboss.remoting.transport.socket.ServerThread.dorun(ServerThread.java:
398)
        at
org.jboss.remoting.transport.socket.ServerThread.run(ServerThread.java:
239)

Please help me.
Thank you