osgi users' forum uk - osgi release 4 v4.2 spec overview - peter kriens

OSGi Next

Peter KriensOSGi Evangelist

dinsdag 14 juli 2009

OSGi Service PlatformCore Specification


Planning 4.2

• Core released for approval June 10

• Working on the final draft for Compendium as we speak

• Compendium : July 10

• Enterprise Release Autumn

• Residential Release Spring 2010


Legend


Legend

BundleA

BundleB


Legend

BundleA

BundleB

Service


Legend

BundleA

BundleB

Service

getService

registerService


Legend

BundleA

BundleB

Service

getService

BundleC

registerService


Legend

BundleA

BundleB

Service

getService

BundleC

registerService

addServiceListener


Legend

BundleA

BundleB

Service

getService

BundleC

registerService

Call/DependencyDirection addServiceListener


Core

• Launching

• Bundle Tracker

• Bundle-License Header

• Service Hooks

• Negative Permissions


Launching

• To be inside a framework …

• Or outside a framework ...

• That’s the question!


Launching

• Standardizes launching different frameworks

• Will enable generic launchers

• Allows you to embed a framework in your application!


LaunchingMap<String,String> p = new HashMap<String,String>();

List<String> impls = getMetaInfServices(

loader, FrameworkFactory.class.getName());

if (impls.size() != 1) throw new RuntimeException( "Too many frameworks: "+ impls);

Class<?> clazz = loader.loadClass(impls.get(0)); FrameworkFactory factory = (FrameworkFactory) clazz .newInstance(); Framework fw = factory.newFramework(p); Bundle b = fw.installBundle( “http://.../load/…”); b.start();


Bundle Tracker

• Simple tool a la Service Tracker to track bundles

• Very useful for extenders

• Bundles that provide additional functionality based on data in a bundle

• Tracks a set of states

• Handles all concurrency issues


Service Hooks

• FindHook

• Intercept getServiceReference(s)

• EventHook

• Intercept Service Event delivery

• ListenerHook

• Find out who is listening to what


Service HooksBundle

A

BundleB


Service HooksBundle

A

BundleB

ProxyBundle


Service HooksBundle

A

BundleB

FindHookEventHook

ProxyBundle


Service HooksBundle

A

BundleB

FindHookEventHook

ProxyBundle

ListenerHook


Negative Permissions

• Java 2 Permissions are only positive

• That is, you grant a permission P

• PackagePermission(com.acme,IMPORT)

• Very hard to say, all permissions except P

• Lack of deny permissions


Negative Permissions

DENY { [...BundleSignerCondition "cn=*, o=ACME" "!" ] (...PackagePermission "com.acme.secret.*" "import,exportonly" ) } ALLOW { (...PackagePermission "*" "*" ) }


Compendium

• Initial Provisioning

• Bundle Tracker

• Declarative Services

• Remote Services

• Blueprint Extender


Remote Services

• RFC 119

• Formerly Distributed OSGi

• Distribution Software uses services to:

• Maps a service to/from a remote system

• Uses a service to abstract a communication endpoint


Remote Services

DistributionProvider

DistributionProvider

X’

BundleB


Remote Services

XDistribution

ProviderDistribution

Provider

X’

BundleB


Remote ServicesBundle

A

XDistribution


Provider

X’

BundleB



A

XDistribution


Provider

X’

BundleB

exports



A

XDistribution


Provider

X’

BundleB

exports imports



A

XDistribution


Provider

X’

BundleB

exports imports

Framework 1 Framework 2


Remote Services

• Service Properties define the interaction

• Intents specify the required/provided capabilities

• Filters used to match

• Service Component Architecture (SCA)

• Interaction specified, not mandated

• Flexible configuration options


Service Properties<other properties>

service.exported.intents

service.intents

service.exported.intents.extra

service.exported.interfaces

service.exported.configs

<other properties>


objectClass

service.imported.configs

service.imported

remote.intents.supported

remote.configs.supported

Distribution Provider



Service Properties<other properties>


service.intents

service.exported.intents.extra

service.exported.interfaces

service.exported.configs

<other properties>


objectClass

service.imported.configs

service.imported

remote.intents.supported

remote.configs.supported

Distribution Provider


endpoint


Blueprint Extender

• RFC 124

• Provides Spring DM Functionality

• Blueprint Extender uses XML definitions in bundle to create & wire application objects

• Namespace Handler services, not yet :-(

• Provides damping

• Proxies services


Blueprint Extender

XML


Blueprint Extender

XMLBlueprintContainer


BeanMetadata

ServiceMetadata

ReferenceMetadata

Blueprint Extender



BeanBeanMetadata

ServiceMetadata

ReferenceMetadata

Blueprint Extender



Bean

Service

BeanMetadata

ServiceMetadata

ReferenceMetadata

Blueprint Extender



Bean

Service

BeanMetadata

ServiceMetadata

ReferenceMetadata

Blueprint Extender


Reference


Bean

Service

BeanMetadata

ServiceMetadata

ReferenceMetadata

Blueprint Extender


ApplicationObjects

Reference


Metadata

NonNull

Metadata

Null

Metadata

Component

Metadata

Service

Metadata

Service

Reference

Metadata

Bean

Metadata

Value

Metadata

Collection

Metadata

Map

Metadata

Bean

Argument

Bean

Property

ListenerRegistration

Listener

IdRef

Metadata

Ref

Metadata

Target

Props

Metadata

Reference

Metadata

Ref

Collection

Metadata

Map

Entry


Damping Reference

serviceobjectApp proxy

serviceobject

serviceobject


Damping Reference

App proxy

serviceobject

serviceobject


Damping Ref-list

serviceobjectApp proxy

serviceobject

serviceobject

List

proxy

proxy


Enterprise

• Transactions

• JDBC Database Access

• JMX

• JNDI

• JPA

• Connectors


Experimental

• TSL

• Nested Frameworks

• OBR


TSL

• A Tiny Script Language

• Feels like a shell

• Acts like a script language

• Uses reflection, but simplifies syntax

• No new commands

• Will become Felix project


TSLTelnetShell

ConsoleShell

...Shell

OSGiConvert.

EclipseConvert.

FelixConvert.

BasicCmnds

FrameWorkCmnds

ThreadIO

ThreadIO

CommandShell

Converter

* osgi.command.name=xxx osgi.command.function=yyy

...Cmnds

TSLImpl


TSL $ echo Hello World Hello World $ echo <bundle 1> initial@reference:file:org.eclipse.osgi.util_3.1.200.v20070605.jar/ [1]

$ ls eclipse eclipse.ini load runner

$ ls /Ws aQute felix-trunk osgi osgi-books


TSL

$ <bundle 6> headers Tool Bnd-0.0.169 Bundle-Activator aQute.fileinstall.FileInstall Export-Package aQute.fileinstall ... Created-By 1.6.0_01 (Sun Microsystems Inc.) Bnd-LastModified 1184160147361 Bundle-Version 1.3 Bundle-ManifestVersion2 Manifest-Version 1.0 Import-Package aQute.fileinstall, ... Bundle-Name biz.aQute.fileinstall Bundle-Description This bundle watches a .... Bundle-SymbolicName biz.aQute.fileinstall


TSL $ help={each <<$it class> declaredmethods> {$it name }} aQute.shell.runtime.Closure@90a284 $ help <bundle 6> loadClass getResource ... checkLoader closeBundleLoader getLoaderProxy

$ echo $exception E: java.lang.NullPointerException $ echo $exception java.lang.NullPointerException $ $exception printstacktrace $ // the output is temporarily on reall stderr ...


Nested Frameworks

• Application Server Vendors want scoping of applications …

• Basic Idea OSGi is:

• The Application == the set of installed bundles

• Compromise:

• All Frameworks to be nested


Framework P

Nested Frameworks

SystemBundle


Framework P

Nested Frameworks

SystemBundle

CompositeBundle


Framework P

Nested Frameworks

Framework CSystemBundle

CompositeBundle


Framework P

Nested Frameworks

Framework CSystemBundle System

Bundle

CompositeBundle


Framework P

Nested Frameworks


Bundle

SurrogateBundle

CompositeBundle


Framework P

Nested Frameworks


Bundle

SurrogateBundle

CompositeBundle

AppBundle

A


Framework P

Nested Frameworks


Bundle

SurrogateBundle

CompositeBundle

AppBundle

A

AppBundle

B


Java Modularity


Java Modularity

294dinsdag 14 juli 2009

Java Modularity

2947


Java Modularity

42dinsdag 14 juli 2009

Java Modularity


Java Modularity

module


Java Modularity

module class Foo {}

public class Bar { module int foo() {}}

module interface Baz {}


Java Modularity

Visibilityvs

Accessibility


Visibility

ClassS

ClassT

ClassT


Visibility

ClassS

ClassT


Visibility

ClassS

ClassT

ModuleSystem


Accessibility

public

package

module

private


Accessibility

ClassS


class

Accessibility

ClassS

ClassT


package

class

Accessibility

ClassS

ClassT

Class U


module

package

class

Accessibility

ClassS

ClassT

Class U

ClassV


module

package

class

Accessibility

ClassS

ClassT

ClassW

Class U

ClassV


Is JSR 294 aMeta Module System? (Implemented by OSGi™, Jigsaw, Guice, …)


Is JSR 294 aMeta Module System? (Implemented by OSGi™, Jigsaw, Guice, …)

No Java™ Standard for

Modules!dinsdag 14 juli 2009

Bundle

OSGi Modules: Bundle = Module

module


Bundle

OSGi Modules: Bundle = Multiple Modules

module A

module B


Bundle BBundle A

module

OSGi Modules: Modules Cross Bundles


Bundle

OSGi Modules: Nested?

module A

module B


Module Dependencies

Bundle A

module A

Bundle B

module B


Module Dependencies

Bundle A

module A

Bundle B

module B

requires

provides

permits


Module Dependencies

Bundle A

module A

Bundle B

module B

requires

provides

permits?dinsdag 14 juli 2009

Containers?

π 3.14


Containers?

π 3.14JLS


Containers?

π 3.14JLS JVM


Containers?


container com.acme

Containers?


container com.acme

Containers?

module com.acme.foo;


container com.acme

Containers?


module com.acme.foo;module bar;


container com.acme

Containers?



module com.acme.foo;module bar;private package one;

module com.acme.foo;module fiz;public package one;


container com.acme

Containers?



module com.acme.foo;module bar;private package one;

module com.acme.foo;module fiz;public package one;

module com.acme.foo;module bar;package one;import module fiz;module class A {}

module com.acme.foo;module fiz;package two;

class B {}


Q&A


osgi users' forum uk - osgi release 4 v4.2 spec overview - peter kriens

Technology

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legendbundleabundleb

service tracker

intents service

remote system

service tofrom

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