Migration of JOnAS EJB Session, Entity, Home and Remote, with ProActive Interposition objects

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Migration of JOnAS EJB Session, Entity, Home and
Remote, with ProActive Interposition objects

• Baomin Xu

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Plan of the Talk

• 1. Introduction to ProActive
• 2. Migration of JOnAS EJB Session, Entity, Home
  and Remote
• 3. Conclusion and Future Work

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• Introduction to ProActive

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ProActive Model

• The application is structured in subsystems.
• Each subsystem is composed of one active object
  and some passive objects
• All objects (both active and passive) may have
  references onto active objects
• If an object o1 has a reference onto a passive
  object 02, then o1 and o2 are part of the same
  subsystem.
• Only the active object is known to objects
  outside of the subsystem

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ProActive Active Objects

• An active object is composed of several objects
  
• The object itself (a standard Java object )
• The body receiving calls on the active object,
  storing these calls in a queue of pending calls
• The queue of pending requests

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ProActiveCreating Active Object

• Class-based
• class pA extends A implements Active
• A a (A)ProActive.newActive(pA,params, node)
• Instantiation-based
• A a (A)ProActive.newActive(A,params,
  node)
• Object-based
• A a new A (obj, 7)
• a (A)ProActive.turnActive (a, node)

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• Migration of JOnAS EJB Session, Entity, Home and
  Remote

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Past Work

• The work about how to migrate a JOnAS EB
  was done by Laurent Vaills, Alexandre Guyot, and
  Nicolas Guillier.
• The approach adopted by them is to
  modify the EB source code directly.

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Goal Of My Research

• Implementing the migration of both a JOnAS EB and
  its Home and Remote
• Minimizing the direct modification to EB source
  code

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Approach to Migration of JOnAS EB and Its Home
and Remote

• Turning the standard Object into an Active
  Object
• Implementing the migration

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Approach to Turn the EJB Objects into Active
Objects
Modification of the JOnAS source code -
GenIC tool - Other sources
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Why Do We Need to Modify the GenIC Tool

• It generates the container classes for a given
  EB
• It generates source code for a given EB s Home
  and Remote interface
• It generates stubs and skeletons for a given
  EBs Home and Remote interface
• .

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Why the Modification Will Be Done?

• Restrictions on reifiable objects in ProActive
• - Classes without a no-argument
  constructor cannot be
• reified.
• - Final classes cannot give birth to active
  object
• - Same thing for non-public classes
• Giving the standard EJB objects migrable
  properties , namely turning them into migrable
  active objects

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The Details of Modification to GenIC Tool(1)

• File name GenICEntityHome
• Modifications turn JOnAS objects into active
  objects, import ProActive Library, add
  non-argument constructor, add serializable
  interface.
• Lines 50
• Typical clauses(Turning an EB into an active
  object)
• void genCreate(Method method) throws
  GenICException
• ...
• src.indentPlus()
• src.println("ProActive.turnActive(eb,Ser
  ver.node)")
• ...
• src.indentMinus()
• src.println(" ")

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The Details of Modification to GenIC Tool(2)

• File name GenICEntityRemote
• Modifications import ProActive Library, add
  non-argument constructor, add serializable
  interface
• Lines 20
• Typical clauses(add non-argument constructor
  for EB s Remote)
• void genVoidConstructor () throws
  GenICException
• src.println("public "
  wrpRemoteBaseName  
•  "() throws RemoteException")
• src.indentPlus()
• src.indentMinus()
• src.println("")
• ...

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The Details of Modification to GenIC Tool(3)

• Files GenICSessionHome, GenICSessionRemote
• Do the same work as GenICEntityHome,GenICEnti
  tyRemote respectively
• Files GenICHome, GenICRemote(5 lines
  respectively)
• add abstract function declaration , function
  call clauses, and modify class declaration. For
  example(GenICRemote)
• src.println("public class
  "wrpRemoteBaseName
• " extends
  "getSuperClass()
• " implements "
• ejbRemoteName",
  Active,Serializable")

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The Details of Modification to Other Sources of
JOnAS

• File names JBeanSession, JBeanSessionSf,
  JBeanSessionSl, JSessionHome, JContextSession,
  JContainerImple, JEntityHome, .
• Modifications add non-argument constructor,
  add serializable interface
• Lines 5 respectively
• Typical clauses
• private void writeobject(java.io.objectoutStream
  out) throws java.io.IOException
• out.defaultWriteObject()

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Migration of JOnAS EB(1)
VM 1
Server
Container
EJBHome Skeleton
EJBHome
EJBHomeStub
Client
EB
EJBObjectStub
EJBObject Skeleton
EJBObject
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Migration of JOnAS EB(2)
VM 1
Server
VM 2
EJBHome Skeleton
Container
EJBHome
EJBHomeStub
EB
Client
EJBObjectStub
EJBObject Skeleton
EJBObject
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Migration of JOnAS EB(3)
VM 1
Server
VM 2
EJBHome Skeleton
Container
EJBHome
EJBHomeStub
EB
Client
EJBObjectStub
EJBObject Skeleton
EJBObject
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Migration of JOnAS Remote
VM 1
VM 2
Server
Container
EB
EJBHome Skeleton
EJBHome
EJBHomeStub
Client
EJBObject
EJBObjectStub
EJBObject Skeleton
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Migration of JOnAS Home
VM 1
VM 2
Server
Container
EJBHome
EJBHome Skeleton
EJBHomeStub
EB
Client
EJBObject Skeleton
EJBObjectStub
EJBObject
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Conclusion and Future Work

• ProActive provides a scheme to implement the
  migration of JOnAS EB and its Home and Remote
• ProActive provides a method to dynamic deploy
  JOnAS EJB
• ProActive provides an approach to give JOnAS
  activity.
• Implementing the migration of Message-driven Bean