net.walend.lyophil.ejb.ejbbeans
Class IdentifierSourceEJBBean

java.lang.Object
  |
  +--net.walend.lyophil.ejb.ejbbeans.IdentifierSourceEJBBean

All Implemented Interfaces:

javax.ejb.EnterpriseBean, java.io.Serializable, javax.ejb.SessionBean

public class IdentifierSourceEJBBean

extends java.lang.Object

implements javax.ejb.SessionBean

This session bean wraps an IdentifierSource and puts all calls to that IdentifierSource inside their own transactions. This design keeps the same identifier from getting used twice.

Since:

20010801

Author:

David Walend

Field Summary

private javax.ejb.SessionContext	ctx
private IdentifierSource	idSource

Constructor Summary

IdentifierSourceEJBBean()

Method Summary

boolean	checkSetUp() make sure the backing storage is set up correctly
java.io.Serializable	createID() Return a new identifier Object.
void	ejbActivate()
void	ejbCreate()
protected java.lang.Object	ejbCreateGuts(java.lang.String className) This method constructs the "guts" object for this Session bean.
void	ejbPassivate()
void	ejbRemove()
java.io.Serializable	peekNextID() Returns the next id to be created, without assigning it as in use.
void	setSessionContext(javax.ejb.SessionContext context)
void	setUp() set up the backing storage
void	tearDown() clean up the backing storage

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

idSource

private IdentifierSource idSource

ctx

private javax.ejb.SessionContext ctx

Constructor Detail

IdentifierSourceEJBBean

public IdentifierSourceEJBBean()

Method Detail

ejbCreateGuts

protected java.lang.Object ejbCreateGuts(java.lang.String className)
                                  throws javax.ejb.CreateException

This method constructs the "guts" object for this Session bean. The guts keeps the funcitonality separate from the session bean code, making it easier to test and to reuse.

ejbCreate

public void ejbCreate()
               throws javax.ejb.CreateException

setSessionContext

public void setSessionContext(javax.ejb.SessionContext context)

Specified by:

setSessionContext in interface javax.ejb.SessionBean

ejbActivate

public void ejbActivate()

Specified by:

ejbActivate in interface javax.ejb.SessionBean

ejbPassivate

public void ejbPassivate()

Specified by:

ejbPassivate in interface javax.ejb.SessionBean

ejbRemove

public void ejbRemove()

Specified by:

ejbRemove in interface javax.ejb.SessionBean

createID

public java.io.Serializable createID()

Return a new identifier Object. The Object should be immutable and unique inside the system. Longs or RMI identifiers are a good choice. Your implementation should periodically log information about how quickly it's using up unique identifiers.

Throws:

an - IdentifierUnavailableException if the IdentifierSource can't get a new unique Object.

a - LastIdentifierUsedException if the IdentifierSource is completely out of unique Objects.

peekNextID

public java.io.Serializable peekNextID()

Returns the next id to be created, without assigning it as in use. I use this method for testing.

checkSetUp

public boolean checkSetUp()

make sure the backing storage is set up correctly

Throws:

<{PersistenceFailureException}>

setUp

public void setUp()

set up the backing storage

Throws:

<{PersistenceFailureException}>

tearDown

public void tearDown()

clean up the backing storage

Throws:

<{PersistenceFailureException}>