EHCache + Hibernate Error: Cached Item Was Locked

Question

I have been trying to figure out this problem for a month or so now, and it has been driving me crazy.

Basically I want to keep this from happening:

FINEST: Cached item was locked: com.cache.dataobject.Part.parts#0
FINE: select parts0_.mainPart_id as mainPart3_1_, parts0_.id as id1_, parts0_.id as id182_0_, parts0_.mainPart_id as mainPart3_182_0_, parts0_.PART_NAME as PART2_182_0_ from SourcePart parts0_ where parts0_.mainPart_id=?

Since that select statement isn't really necessary.

If you have any ideas please help. It feels like I have tried a million different things to no avail.

I have included the DAO EJB I am using, the Cache/Hibernate Debug Log, the JPA Entities, and the Test code I have been using.

Debug Log:

INFO: CALLED PERSIST
INFO: com.cache.dao._CacheDao_Serializable@65e34c
FINEST: Cache lookup: com.cache.dataobject.Part#0
FINEST: Cache miss: com.cache.dataobject.Part#0
FINEST: Cache lookup: com.cache.dataobject.SourcePart#1
FINEST: Cache miss: com.cache.dataobject.SourcePart#1
FINEST: Cache lookup: com.cache.dataobject.SourcePart#2
FINEST: Cache miss: com.cache.dataobject.SourcePart#2
FINEST: Invalidating: com.cache.dataobject.Part.parts#0
FINE: insert into Part (PART_NAME, id) values (?, ?)
FINE: insert into SourcePart (mainPart_id, PART_NAME, id) values (?, ?, ?)
FINE: insert into SourcePart (mainPart_id, PART_NAME, id) values (?, ?, ?)
FINE: update SourcePart set mainPart_id=? where id=?
FINE: update SourcePart set mainPart_id=? where id=?
FINEST: Inserting: com.cache.dataobject.Part#0
FINEST: Inserted: com.cache.dataobject.Part#0
FINEST: Inserting: com.cache.dataobject.SourcePart#1
FINEST: Inserted: com.cache.dataobject.SourcePart#1
FINEST: Inserting: com.cache.dataobject.SourcePart#2
FINEST: Inserted: com.cache.dataobject.SourcePart#2
FINEST: Releasing: com.cache.dataobject.Part.parts#0

INFO: CALLED MULTI MERGE
FINEST: Cache lookup: com.cache.dataobject.Part#0
FINEST: Cache hit: com.cache.dataobject.Part#0
FINEST: Cache lookup: com.cache.dataobject.Part#0
FINEST: Cache hit: com.cache.dataobject.Part#0
FINEST: Cache lookup: com.cache.dataobject.Part.parts#0
FINEST: Cached item was locked: com.cache.dataobject.Part.parts#0
FINE: select parts0_.mainPart_id as mainPart3_1_, parts0_.id as id1_, parts0_.id as id182_0_, parts0_.mainPart_id as mainPart3_182_0_, parts0_.PART_NAME as PART2_182_0_ from SourcePart parts0_ where parts0_.mainPart_id=?
FINEST: Caching: com.cache.dataobject.SourcePart#1
FINEST: Item was already cached: com.cache.dataobject.SourcePart#1
FINEST: Caching: com.cache.dataobject.SourcePart#2
FINEST: Item was already cached: com.cache.dataobject.SourcePart#2
FINEST: Caching: com.cache.dataobject.Part.parts#0
FINEST: Cached: com.cache.dataobject.Part.parts#0
FINEST: Invalidating: com.cache.dataobject.Part.parts#0
FINEST: Invalidating: com.cache.dataobject.Part#0
FINE: update Part set PART_NAME=? where id=?
FINEST: Invalidating: com.cache.dataobject.SourcePart#1
FINE: update SourcePart set mainPart_id=?, PART_NAME=? where id=?
FINEST: Invalidating: com.cache.dataobject.SourcePart#2
FINE: update SourcePart set mainPart_id=?, PART_NAME=? where id=?
FINEST: Updating: com.cache.dataobject.Part#0
FINEST: Updated: com.cache.dataobject.Part#0
FINEST: Updating: com.cache.dataobject.SourcePart#1
FINEST: Updated: com.cache.dataobject.SourcePart#1
FINEST: Updating: com.cache.dataobject.SourcePart#2
FINEST: Updated: com.cache.dataobject.SourcePart#2
FINEST: Releasing: com.cache.dataobject.Part.parts#0

DAO Code:

    public Part addPart(Part part){
        System.out.println("CALLED PERSIST");
        System.out.println(this);

        em.persist(part);

        return part;
    }

    public List<Part> updateParts(List<Part> parts){
        System.out.println("CALLED MULTI MERGE");

        for(Part p: parts){
         em.merge(p);
        }

        return parts;
    }

Test Code:

       CacheDaoRemote dao = (CacheDaoRemote) ctx.lookup("ejb/CacheDao");

       List<Part> partsList = new ArrayList<Part>();

       int i = 0;
   Part computer = new Part();
   computer.setId(i++);
   computer.setName("Computer");

   List<SourcePart> parts = new ArrayList<SourcePart>();

   SourcePart cpu = new SourcePart();
   cpu.setId(i++);
   cpu.setName("CPU");
   cpu.setMainPart(computer);

   SourcePart monitor = new SourcePart();
   monitor.setId(i++);
   monitor.setName("Monitor");
   monitor.setMainPart(computer);

   parts.add(cpu);
   parts.add(monitor);

   computer.setParts(parts);

   dao.addPart(computer);

   partsList.add(computer);
   computer.setName("HPComputer " + uniqueNumber);
   cpu.setName("HPCPU "+ uniqueNumber);
   monitor.setName("HPMonitor "+ uniqueNumber);


         dao.updateParts(partsList);

SourcePart:

package com.cache.dataobject;

import static javax.persistence.CascadeType.ALL;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;

import org.hibernate.annotations.CacheConcurrencyStrategy;


@Entity
@org.hibernate.annotations.Cache(usage=CacheConcurrencyStrategy.READ_WRITE)

public class SourcePart implements Serializable {

    private int id;
    private String name;
    private static final long serialVersionUID = 1L;
    private Part mainPart;

    public SourcePart() {
     super();
    }

    @Id
    public int getId() {
     return this.id;
    }

    public void setId(int id) {
     this.id = id;
    }

    @Column(name = "PART_NAME")
    public String getName() {
     return this.name;
    }

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

    @ManyToOne(cascade = ALL)
    public Part getMainPart() {
     return mainPart;
    }

    public void setMainPart(Part mainPart) {
     this.mainPart = mainPart;
    }



}

Part:

package com.cache.dataobject;

import static javax.persistence.CascadeType.ALL;

import java.io.Serializable;
import java.util.List;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;

import org.hibernate.annotations.CacheConcurrencyStrategy;

/**
 * Entity implementation class for Entity: Part
 * 
 */
@Entity
@org.hibernate.annotations.Cache(usage=CacheConcurrencyStrategy.READ_WRITE)
public class Part implements Serializable {

    private int id;
    private String name;
    private static final long serialVersionUID = 1L;
    private List<SourcePart> parts;

    public Part() {
     super();
    }

    @Id
    public int getId() {
     return this.id;
    }

    public void setId(int id) {
     this.id = id;
    }

    @Column(name = "PART_NAME")
    public String getName() {
     return this.name;
    }

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


    @OneToMany(cascade = ALL,fetch=FetchType.EAGER)
    @JoinColumn(name = "mainPart_id", referencedColumnName = "id")
    @org.hibernate.annotations.Cache(usage=CacheConcurrencyStrategy.READ_WRITE)
    public List<SourcePart> getParts() {
     return parts;
    }


    public void setParts(List<SourcePart> parts) {
     this.parts = parts;
    }

}