Software interactions David Emsellem emsellem@essi.fr I3S Laboratory, France .

transcript

Software interactions

David Emsellememsellem@essi.fr

I3S Laboratory, France

http://noah.essi.fr

Overviewhttp://noah.essi.fr

• No modification on the component• Reusability

• Dynamically• no recompilation• no application restart

storage

notification

collaboration

security

Add capabilities to components, compose and coordinate them

class Agenda {

void addMeeting (Meeting m) throws Exception{ meetingTable.add(m); }

List meetingTable; …}

class Agenda {

void addMeeting (Meeting m) throws Exception{ meetingTable.add(m); display.notify("addMeeting: "+m.toString( )); }

List meetingTable;; Display display; …}

class Agenda {

void addMeeting (Meeting m) throws Exception{ if (security.ckeck(…)) { meetingTable.add(m); display.notify("addMeeting: "+m.toString( )); } else { throw new Exception("Invalid operation"); } }

List meetingTable;; Display display; SecurityService security; …}

class Agenda {

void addMeeting (Meeting m) throws Exception{ if (security.ckeck(…)) { meetingTable.add(m);

database.store(getFullName( ),this); display.notify("addMeeting: "+m.toString( )); } else { throw new Exception("Invalid operation"); } }

List meetingTable;; Display display; SecurityService security; Database database; …}

void addMeeting(Meeting m) throws Exception{ if (security.ckeck(…)) { meetingTable.add(m); } else { throw new Exception("Invalid operation"); }}

void addMeeting(Meeting m) { meetingTable.add(m); display.notify("addMeeting: " +m.toString());}

void addMeeting(Meeting m) { meetingTable.add(m); }

Persistance

Security

Default behaviour

Notification

+void addMeeting(Meeting m) { meetingTable.add(m); database.store(getFullName(),this); }

Life cyclehttp://noah.essi.fr

Interactions: Life cycle

Interaction notification(Object obj, Display display){

obj.* -> obj._call // display.notify(_call)}

Interaction service

agenda1 display1

patterns

interactions

registerPatternInteraction notification(Object obj, Display display){

obj.* -> obj._call // display.notify(_call)}

Pattern registration

Interaction service

agenda1 display1

patterns

interactions

Instanciate(notification,[agenda1,display1])notification

Interaction service

agenda1 display1

patterns

interactions

Pattern instantiation

addRulenotification

Interaction service

agenda1 display1

patterns

interactions

notification#1

addMeeting()

getName()

interaction security(Object obj, SecurityService service){

obj.addMeeting() -> if service.check(_call) then obj._call else exception "UnauthorizedUser" endif }

securityService1

notification

Interaction service

agenda1 display1

patterns

interactions

notification#1

addMeeting()

getName()

registerPattern

Interaction service

agenda1

patterns

interactions

addMeeting()

getName()

notification

notification#1

security

securityService1

display1 Pattern registration

obj.addMeeting() -> if service.check(_call) then obj._call else exception "UnauthorizedUser" endif }

Instanciate(security,[agenda1,securityService1])

Interaction service

agenda1

patterns

interactions

addMeeting()

getName()

notification

notification#1

security

securityService1

display1

agenda1

addRule

addMeeting()

getName()

securityService1

display1

Interaction service

patterns

interactions

notification

notification#1

security

security#1

agenda1

addMeeting()

getName()

securityService1

display1

Interaction service

patterns

interactions

notification

notification#1

security

security#1

Merging

Rule merging

agenda1

addMeeting()

getName()

securityService1

display1

Interaction service

patterns

interactions

notification

notification#1

security

security#1

Invocation

AddMeeting

Implementation

http://noah.essi.fr

Last year : Java

• Released version– http://noah.essi.fr

.Net extension (May 2003 )

Specialized rotor version (Sept. 2003)

Java + J2EE-Jonas

Java : component registration

RMIRegistry

JavaObject

JVM 1 JVM 2

General architecture

Java : interaction instantiation

RMIRegistry

RMI ISL

JavaObject

JVM 1 JVM 2

.Net : component registration

RMIRegistry

HTTPObject

.NET Remoting

JavaObject

JVM 1 JVM 2 Remote .NET Process 1

RMIRegistry

HTTPObject

.NET Remoting

JavaObject

.Net : interaction instantiation

RMIRegistry

HTTPObject

TCPObject

.NET Remoting .NET Remoting

JavaObject

Remote .NET Process 2

.Net : component registration

RMIRegistry

HTTPObject

TCPObject

.NET Remoting .NET Remoting

JavaObject

Remote .NET Process 2

Bridge

.NET RemotingIML

IMLSOAP

.NET : interaction instantiation

Interaction Service

.NET – Life cycle

patterns

interactions

Interaction notification(Object obj, Display display){

obj.* -> obj._call // display.notify(_reifiedCall)}

display1agenda1

Interaction Service

.NET – Life cycle

patterns

notification

registerPatternInteraction notification(Object obj, Display display){

obj.* -> obj._call // display.notify(_reifiedCall)}

display1agenda1

Pattern Registration

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

Instanciante(notification,[agenda1,display1])

display1agenda1

Interaction instantiation

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

Java to XML marshallingXMLXML

display1agenda1

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

XMLXML

display1agenda1

.NET objects published via HTTPare directly accessible from Java as simple Web Services. For other components a proxy is used to reach .NET world

Java to XML marshalling

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

Serialization Java → XML

Envoi des règlesHTTP - WebServices

XMLXML

display1agenda1

addMeeting()

getName()

XML to .NET unmarshalling

Interaction Service

.NET – Life cycle

patterns

interactions

obj.addMeeting() -> if service.check(_reifiedCall) then obj._call else throw new UnauthorizedUser() endif }

notification

notification#1

display1securityService1agenda1

addMeeting()

getName()

Interaction Service

.NET – Life cycle

patterns

notificationregisterPattern

notification

security

notification#1

addMeeting()

getName()

Pattern registration

obj.addMeeting() -> if service.check(_reifiedCall) then obj._call else throw new UnauthorizedUser() endif }

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

notification

security

notification#1

security#1

addMeeting()

getName()

Instanciate(security,[agenda1,securityService1])

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

Rule sendingHTTP – Web Services

XMLXML

addMeeting()

getName()

security

security#1

Java to XML marshalling

XML to Java unmarshalling

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

addMeeting()

getName()

security

security#1

AddMeeting

Invocation

Merged rule isn’t yetresolved

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

addMeeting()

getName()

security

security#1

AddMeeting

mergeRule()

Call to a Java merging Web Service

Rules are marshalled from .NET to XML, and then unmarshalledfrom XML to their correspondingJava representation

MergingWeb Service

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

addMeeting()

getName()

security

security#1

AddMeeting

+=MergingMerging

Web Service

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

addMeeting()

getName()

security

security#1

AddMeeting

mergeRule() return

Return merging result

to the component

MergingWeb Service

Interaction Service

.NET – Life cycle

patterns

notification

interactions

notification#1

addMeeting()

getName()

security

security#1

AddMeetingRule execution

Next execution doesn’tneed a new merging

Class instrumentation (1)

class Agenda : IAgenda{

public void addMeeting (Meeting m){

class Agenda : IAgenda{

public void addMeeting_Intercepted (Meeting m){

} public void addMeeting (Meeting m){ if (methodTable.isSlotOn(1)){ methodTable.invoke(1,new Object[]{m}) } else { addMeeting_Intercepted(m); } }

private NoahMethodTable methodtable;

Class instrumentation (2)

• Each business method needs to be wrapped

• An additional field handles instance vtable

• Special control methods are added to the class (addRule, removeRule …)

• 2 methods for handling the « same » method behaviour

2 MethodDesc, IL code, stubs, vtable slots …

• Interception cost is paid even if no instance has redefined the behaviour of the corresponding method

• When executing an alternative behaviour we also pay the cost of creation of the parameters array

Class instrumentation (3) : drawbacks

Another approach: working with the rotor code

Advantages

• access to the object memory representation

• Allows us to avoid the class instrumentation stage

• Principle: each user method can potentially be redefined

Methods are wrapped on a as-needed basis When no instance has modified a method behaviour,

we don’t intercept the call

• access to the invocation mechanism

• Rules can be executed by the execution engine

• We can try to suppress the rule interpretation stage

EEClass

x Objectheader

Instancedata

FieldDesc

MethodDesc

Prebtub pointer Prestub

Application Domain

ClassLoader

Module

Assembly

Interfacemap

JMI ThunkCompiled

Sync record

SyncBlock table SyncBlock

GCDesc

MethodTable

Runtime data structures in rotor

EEClass

x Objectheader

Instancedata

FieldDesc

MethodDesc

Prebtub pointer Prestub

Application Domain

ClassLoader

Module

Assembly

Interfacemap

JMI ThunkCompiled

Sync record

SyncBlock table SyncBlock

GCDesc

MethodTable

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

Instance data

SLOT[0]

SLOT[n]

SLOT[i] Prologue

User Code

Epilogue

method tablesinstances

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

m_pInstanceMT

Instance data

SLOT[0]

SLOT[n]

SLOT[i] Prologue

User Code

Epilogue

Interacting object instance has an extra field: its own Vtable

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

m_pInstanceMT

Instance data

SLOT[0]

SLOT[n]

SLOT[i] Prologue

User Code

Epilogue

addRule

What happens when adding a rule?

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

m_pInstanceMT

Instance data

SLOT[0]

SLOT[n]

SLOT[i]

Prologue

User Code

Epilogue

A per-instance vtable is built

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

m_pInstanceMT

Instance data

SLOT[0]

SLOT[n]

SLOT[i]

interacting rule code(no prologue)

Prologue

User Code

Epilogue

Rule instances are JIT compiled to native code (IL like)

JMI Thunk

native code

GCDesc

MethodTable

GCDesc

m_pMethodTable

m_pInstanceMT

Instance data

SLOT[0]

SLOT[n]

SLOT[i]

interacting rule code(no prologue)

Prologue

User Code

Epilogue

mov eax [this + 4] // m_pInstanceMT cmp eax 0 // if null je userCode // default behaviour mov eax [eax +12] // dispatch instanceMT cmp eax 0 je userCode call eax // user code addr on stack

Target method is updated• MethodDesc is marked , and while it’s beeing (re)jitted a stub is added just after the prologue

Conclusion

• We have a way to express interactions between components in a language independent way (ISL)

• The same server manages interactions for Java and .NET components

• A Rotor version will take benefits of the runtime knowledge to achieve some optimizations

• Available as a single library, and graphical tools to control the interaction graph of the application

Questions

http://noah.essi.fr

Software interactions David Emsellem emsellem@essi.fr I3S Laboratory, France .

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