0 Replies Latest reply on Oct 20, 2015 3:00 AM by bhimaraj

Container Managed Transaction between two session beans in ejb3 and jboss5.0.1.GA

bhimaraj Oct 20, 2015 3:00 AM

I have three tables server_detail, server_group, server_group_mappping and the entity classes as below. (have not given the full code details)

@Entity

@Table(name = "server_detail")

public class ServerBean implements Serializable {

private static final long serialVersionUID = 1L;

@Id

@GeneratedValue(strategy = GenerationType.IDENTITY)

@Column(name = "server_id")

private Integer ServerId;

@Column(name = "name")

private String serverName;

....

}

@Entity

@Table(name = "server_group")

public class ServerGroupBean implements Serializable {

private static final long serialVersionUID = 1L;

@Id

@GeneratedValue(strategy = GenerationType.IDENTITY)

@Column(name = "group_id")

private Integer groupId;

@Column(name = "name")

private String groupName;

....

}

@Entity

@IdClass(GroupMapPK.class)

@Table(name = "server_group_mapping")

public class ServerGroupMapBean implements Serializable {

private static final long serialVersionUID = 1L;

@Id

@Column(name = "group_id")

private Integer groupId;

@Id

@Column(name = "server_id")

private Integer serverId;

....

}

Each Entity Bean class having one wrapper class, to manage operations on entity bean as below

@Stateless

@Local

public class ServerClient implements ServerLocal {

@PersistenceContext

private EntityManager em;

public ServerClient() {

}

public ServerBean create(java.lang.String name) {

ServerBean bean = new ServerBean(name);

em.persist(bean);

return bean;

}

public ServerBean update(ServerBean bean){

return (em.contains(bean) ? bean : em.merge(bean));

}

public void remove(ServerBean bean) {

em.remove(em.contains(bean) ? bean : em.merge(bean));

}

@Stateless

@Local

public class ServerGroupClient implements ServerGroupLocal {

@PersistenceContext

private EntityManager em;

public ServerGroupClient() {

}

public ServerGroupBean create(java.lang.Integer name) {

ServerGroupBean bean = new ServerGroupBean(name);

em.persist(bean);

return bean;

}

public ServerGroupBean update(ServerGroupBean bean){

return (em.contains(bean) ? bean : em.merge(bean));

}

public void remove(ServerGroupBean bean) {

em.remove(em.contains(bean) ? bean : em.merge(bean));

}

@Stateless

@Local

public class ServerGroupMapClient implements ServerGroupMapLocal {

@PersistenceContext

private EntityManager em;

public ServerGroupMapClient() {

}

public ServerGroupMapBean create(java.lang.Integer serverId,java.lang.Integer groupId ) {

ServerGroupMapBean bean = new ServerBean(serverId, groupId);

em.persist(bean);

return bean;

}

public ServerBean update(ServerBean bean){

return (em.contains(bean) ? bean : em.merge(bean));

}

public void remove(ServerBean bean) {

em.remove(em.contains(bean) ? bean : em.merge(bean));

}

I am using MYSQL (innoDB Engine) for the tables and the their relation mapping amound the tables.

Now, I have GroupManager session Bean class, which maintains the server_group and server_group_mapping table transactions. When ever i create server group and the members, i have to do following transaction.

1. First, add group id and group name to server_group table

2. Second, map groupid with server id in server_group_mapping table

Following is the code.

@Stateless

@Local

public class GroupManagerBean implements GroupManagerLocal {

@Resource

private SessionContext context;

private static GroupLocal GroupLocal;

private static GroupMapLocal GroupMapLocal;

public GroupManagerBean() {

GroupLocal = ServiceLocator.getGroupLocal();

smscMapLocal = ServiceLocator.getGroupMapLocal();

}

public void addGroup(GroupBean bean, Integer serverId){

group = GroupLocal.create(bean.getGroupName()); ---> 1

...

GroupMapLocal.create(group.getGroupId(), serverId); ----> 2

}

ServiceLocator class is the location where can i lookup all my beans.

Bydefault, in ejb3 transaction attribute is required. if i execute addGroup() method. m getting following exception.

javax.ejb.EJBTransactionRolledbackException: EntityManager must be access within a transaction

at org.jboss.ejb3.tx.Ejb3TxPolicy.handleInCallerTx(Ejb3TxPolicy.java:115)

at org.jboss.aspects.tx.TxPolicy.invokeInCallerTx(TxPolicy.java:130)

at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxInterceptor.java:194)