presentation - Spring.NET

© Siemens AG, Michael Stal

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1


Spring.NET

Introduction and Overview


Michael.Stal@siemens.com



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Content

1.
Motivation

2.
Dependency Injection Basics

3.
Spring.NET Fundamentals

4.
Spring.NET AOP

5.
Further Ingredients

6.
Summary

7.
References

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Motivation

•
Spring.NET is

•
an application framework for
buidling Enterprise .NET
applications

•
an IoC Container (Inversion of
Control) that manages and
injects dependencies on behalf
of developers (DI =
Dependency Injection)

•
resembles the Java version but
is not a naive port

•
version 1.0 introduces DI and
AOP (Aspect
-
Oriented
Programming). Upcoming
versions will add ASP.NET,
Persistence, Remoting support

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Dependency Injection Explained (0)

What is a Dependency?

A Dependency between a source class X
and a target class Y occurs when each
instance X needs an instance of Y!

But what‘s the problem?

The problem is that X needs to know
how to create the Y instance!

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Dependency Injection Explained (1)

•
Consider the following example:










•
Liability:

•
A depends on way to create or otherwise obtain a B instance


public class A {


public B cb;
// A depends on B


public A() { cb = get_B_Object(...); }


...

}

public class B { ... }

public class Container {


public A createA() {



return new A();


}

}

Dependency resolved by A!

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Dependency Injection Explained (2)

•
Other possibilities include setter injection and constructor
injection (A does not depend on how Bs are created):

public class A {


protected B b1;
// A depends on B


protected B b2;


public A(B b1) { this.b1 = b1; }
// dependency injection


public B B2 { set { this.b2 = value; } }
// dependency injection


...

}

public class B { ... }

public class IoCContainer {


public A createA() {



B b1 = get_B_Object(...);



A a = new A(b1);
// constructor injection



B b2 = get_B_Object(...);



a.B2 = b2;
// setter aka property injection



return a;


}

}

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Dependency Injection Explained (3)

•
But how does the Container know which dependencies to
inject?

class A {


protected B _b;


public B b {


set { b = value;}


}

}

<object id = „a“
type=„A“>


<set
-
prop ref=„b“>

</object>

<object id = „b“
type = „B“/>

Actual
Implementation

Configuration of
Dependencies

IoC Container

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Dependency Injection Explained (4)

•
Yet another possibility is field injection (reflection
-
based):












•
But field injection is generally considered bad design!

public class A {


public B cb;


public A() { ... }


...

}

public class B { ... }

public class IoCContainer {


public A createA() {



A a = new A();



a.b = get_B_Object(...);



return a;


}

}

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IoC Containers for .NET

•
PicoContainer.NET
: lightweight
and highly embeddable IoC
container

•
StructureMap
:

lightweight
Inversion of Control (IoC)
Container written in C#; can
improve the architectural
qualities of .NET apps by
reducing the mechanical costs
of good design techniques

•
Castle
: Tools for application
development including small
IoC container

•
Spring.NET
: full featured IoC
container (port of Java version)

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Spring.NET: General Constituents

•
Spring Core: base library
for DI

•
Spring AOP: enriches
base container with AOP
concepts

•
Spring Web extends
ASP.NET with DI,
bidirectional data binding

•
Spring Services enables
the exposal of PONOs
(Plain Old .NET Objects)
as
Web/Enterprise/Remote
services

•
Spring Data provides a
Data Access Layer. It also
eases ADO.NET

•
Spring.ORM provides
integration of popular
persistence frameworks


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Introduction Example (1)

•
Let us start with a Practice
-
First approach. An object
exampleObject

that depends on other objects:

public class ExampleObject {


private AnotherObject objectOne; // dependencies


private YetAnotherObject objectTwo;


private int i;


public AnotherObject ObjectOne {


set { this.objectOne = value; }


}


public YetAnotherObject ObjectTwo {



set { this.objectTwo = value; }


}


public int IntegerProperty {



set { this.i = value; }


}

}

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Introduction Example (2)

•
The configuration tells Spring.NET how objects depend on
each other:


<object id="exampleObject" type="Examples.ExampleObject,
ExamplesLibrary">


<property name="objectOne" ref="anotherExampleObject"/>


<property name="objectTwo" ref="yetAnotherObject"/>


<property name="IntegerProperty" value="1"/>

</object>


<object id="anotherExampleObject" type="Examples.AnotherObject,
ExamplesLibrary"/>

<object id="yetAnotherObject" type="Examples.YetAnotherObject,
ExamplesLibrary"/>


Object name

Object type: namespace path + class, assembly

Properties referring to other objects: often called dependencies
or collaborators

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On Objects and Factories

•
Spring.NET attempts

•
to reduce dependencies between objects

•
to act as non
-
invasive as possible: almost no dependencies of
application from Spring.NET

•
IObjectFactory

is

•
the actual container that instantiates, manages and configures
collaborating objects.

•
represented by the interface
IObjectFactory

which has many
implementations (such as
XMLObjectFactory
).

•
can be instantiated using
new
-
operator or, even better, via configuration
file. Example:




IResource input = new FileSystemResource ("objects.xml");


IObjectFactory factory = new XmlObjectFactory(input);


•
IApplicationContext

denotes a superset of
IObjectFactory
.

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Configuration

•
Preferred way to create Object Factories and Application
contexts is via configuration:

<configuration>


<configSections>


<sectionGroup name="spring">


<section name="context"
type="Spring.Context.Support.ContextHandler, Spring.Core"/>


<section name="objects"
type="Spring.Context.Support.DefaultSectionHandler, Spring.Core" />


</sectionGroup>


</configSections>


<spring>


<context>


<resource uri="config://spring/objects"/>


</context>


<objects>


...


</objects
>


</spring>

</configuration>

Handlers used for Spring configuration section

Where to find object configuration, e.g. file, assembly, config

Configuration of Spring managed objects

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Configuration cont‘d

•
Now instantiating and using
ObjectFactory

or
ApplicationContext

is simple:



•
Factories provide different methods:




IApplicationContext ctx = ContextRegistry.GetContext();

MyPerson person = (MyPerson) ctx.GetObject(“myPerson");

ID that should appear
in object configuration

IResource input = new FileSystemResource ("objects.xml");

XmlObjectFactory factory = new XmlObjectFactory(input);

object foo = factory.GetObject ("foo"); // gets the object
defined as 'foo'

object bar = factory ["bar"]; // same thing, just using the
indexer

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Object Creation

•
In most cases, objects are created using constructors:


•
Another possibility is using a static factory method of a factory
class:



•
Or as the result of a non
-
static factory method of another
object:




<object id=“myObj" type=“MyNS.MyObject, MyLibrary"/>

<object id=“myObj“
type=“MyNS.MyFactory, MyLibrary"

factory
-
method="CreateInstance"
/>

Type of factory not of
created object!

<object id=“MyFactory" type="..."/>

<object id=“MyObj"

factory
-
method="CreateInstance"

factory
-
object=“MyFactory"/>

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Object Lifecycle

•
Objects per default created as singletons

•
object‘s id / name refers always to same instance

•
lifecycle controlled by Spring

•
Other possibility: prototype (non
-
singleton)

•
new object created for each separate access access to id / name

•
lifecycle controlled by requester, not by Spring factory


<object id=“myObj" type=“MyNS.MyObject, MyLibrary"

singleton="false"
/>

<object name="yetAnotherExample"
type=“MyNS.ExampleObjectTwo, MyLibrary"

singleton="true"
/>

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Types of Dependency Injection

•
Spring .NET supports Property and Constructor Injection:









•
constructor
-
arg
also applicable for factory objects or static
factory methods

<object id=“MyObject" type=“MyNS.MixedIocObject, MyLibrary">


<constructor
-
arg name="objectOne" ref="anotherExampleObject"/>

</object>

<object id="anotherExampleObject" type=“MyNS.Class2, MyLibrary"/>


public class MixedIocObject {


private Class2 objectOne;


public MixedIocObject (Class2 obj) {




this.objectOne = obj;


}

}

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Ordering of Constructor Arguments

•
constructor
-
arg

elements are unordered. Thus, use index:




•
or names:





<object name=“myObj" type=“MyNS.MYObject, NyApp">


<constructor
-
arg
index="0"

value="7500000"/>


<constructor
-
arg
index="1"

value="42"/>

</object>

<object name=“myObj" type=“MyNS.MYObject, NyApp">


<constructor
-
arg
name="years"

value="7500000"/>


<constructor
-
arg
name="ultimateAnswer"

value="42"/>

</object>

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Setting Complex Values

•
Setting complex value types
list
,
set
,
name
-
values
,
dictionaries

are supported:





•
Inlining:







•
Additional Remarks:

•
Spring uses built
-
in TypeConverters to convert from String to target type. It is easy
to define your own custom converters.

•
Special Spring.NET configuration element
<null>

to set values to
null
.

•
Other forms of references to collaborators available: ref local, ref parent

<property name="SomeList">


<list>


<value> string </value>


<ref object="myConnection"/>


</list>

</property>

<object id="outer" type="...">


<property name="target">


<object type="ExampleApp.Answers, ExampleApp">


<property name=“answer" value=“42"/>


</object>


</property>

</object>

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IFactoryObject

•
Interface implemented by objects that are themselves
factories:

•
Object GetObject():

returns instance created by factory

•
Bool isSingleton: true

if factory object returns singletons

•
Type ObjectType:

object type returned by
GetObject()

or
null

if
not known in advance

•
Examples on next slides


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Advanced Dependency Injection

•
It is possible to use other object‘s properties, fields or methods for
setting properties.

•
Spring.NET uses
FactoryObjects

for this purpose.












•
The object
theAge

is instantiated using the person object‘s embedded
spouse.age
property

<object name="person" type="Spring.Objects.TestObject, Spring.Core.Tests">


<property name="spouse">


<object type="Spring.Objects.TestObject, Spring.Core.Tests">


<property name="age" value="21"/>


</object>


</property>

</object>

<object name="theAge"
type="Spring.Objects.Factory.Config.PropertyRetrievingFactoryObject,
Spring.Core">


<property name="TargetObject" ref="person"/>


<property name="TargetProperty" value="spouse.age"/>

</object>

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Advanced Dependency Injection (cont‘d)

•
An example for method
-
based injection:










•
This object will be created by calling the method
GetInstance

(
TargetMethod
) of a
MyClassFactory

object (
TargetType
)
using the specified arguments (
Arguments
)

•
Object can then be used for dependency injection


<object id="myObject"
type="Spring.Objects.Factory.Config.MethodInvokingFactoryObject,
Spring.Core">


<property name="
TargetType
" value="Whatever.MyClassFactory, MyAssembly"/>


<property name="
TargetMethod
" value="GetInstance"/>


<!
--

the ordering of arguments is significant
--
>


<property name="
Arguments
">


<list>


<value>1st</value>


<value>2nd</value>


<value>and 3rd arguments</value>


</list>


</property>

</object>

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Log4Net

•
Another example for a
IFactoryObject

implementation is
log4Net

<objects xmlns="http://www.springframework.net"

xmlns:xsi="http://www.w3.org/2001/XMLSchema
-
instance"

xsi:schemaLocation="http://www.springframework.net

http://www.springframework.net/xsd/spring
-
objects.xsd" >


<object name="
daoLogger
"


type="Spring.Objects.Factory.Config.
Log4NetFactoryObject
, Spring.Core">


<
property name="logName" value="DAOLogger"/>


</object>


<object name="productDao" type="PropPlayApp.SimpleProductDao, PropPlayApp ">


<property name="maxResults" value="100"/>


<property name="dbConnection" ref="myConnection"/>


<property name="log" ref="
daoLogger
"/>


</object>


<object name="myConnection" type="System.Data.Odbc.OdbcConnection,


System.Data">


<property name="connectionstring“


value="dsn=MyDSN;uid=sa;pwd=myPassword;"/>


</object>

</objects>

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Lifecycle Callbacks

•
Spring container can notify objects when they are initialized or
destroyed:









•
Clasa may instead implement interfaces (
IDisposable
,
IInitializingObject
) but then dependencies on Spring.NET
container are introduced

<object id="exampleInitObject" type="Examples.ExampleObject"
init
-
method="init“ destroy
-
method=“cleanup”
/>



public class ExampleObject {



public void Init() {




// do some initialization work



}



public void cleanup() {




// do some destruction work



}


}

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Some Additional Capabilities

•
Autowiring is another option: uses reflection to determine and
resolve dependencies (no config required). Different types of
autowiring possible. Usually, better not to use autowiring.

•
For an object definition
depends
-
on
means: this object
depends on other objects which should be initialized first.

•
Objects can be defined with dependency checking modes ao
that Spring.NET will try to find out if all properties of an object
are defined.

•
Aliasing possible:


•
Object definitions might be abstract. Childs can inherit:

<alias name="fromName" alias="toName"/>

<object id=“parentObj“ abstract=“true”>


<property name="name" value="parent"/>


<property name="age" value="1"/>

</object>

<object id=“childObj" type=“...” parent=“parentObj" init
-
method="Initialize">


<property name="name" value="override"/>

</object>

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Object(Factory)PostProcessors

•
A very powerful feature of Spring.NET are
ObjectPostProcessors and ObjectFactoryPostProcessors:

•
ObjectPostProcessors

•
get invoked before and after object initialization

•
can change object and return changed object to Spring

•
for example used to wrap objects with proxies

•
ObjectFactoryPostProcessors

•
Can change object factories / application contexts such as overwriting
configuration information or accessing it from another source

•
Examples

•
PropertyPlaceHolderConfigurer

•
PropertyOverrideConfigurer

•
Object(Factory)PostProcessors automatically detected by
ApplicationContexts
. Must be manually registered with

ObjectFactories
.

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ApplicationContexts

•
IApplicationContext
objects superset of
IObjectFactory

objects

•
Additional capabilities:

•
Automatic registration of Object(Factory)PostProcessors

•
Loading of hierarchical contexts

•
Access to localized ressources

•
Uniform access to ressources

•
Loosely Coupled Event Propagation

•
Should be always preferred over plain object factories except
for ressource
-
constrained environments

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ApplicationContexts cont‘d

•
Example Hierarchical Contexts:







•
Example Resource Managers:








<spring>


<context>


<resource uri="assembly://MyAssembly/MyProject/root
-
objects.xml"/>


<context name="mySubContext">


<resource uri="file://objects.xml"/>


</context>


</context>

</spring>

IApplicationContex ctx = ContextRegistry.GetContext("mySubContext");

<object name="myResourceManager"
type="Spring.Objects.Factory.Config.ResourceManagerFactoryObject,
Spring.Core">


<property name="baseName">


<value>Spring.Examples.AppContext.MyResource</value>


</property>


<property name="assemblyName">


<value>Spring.Examples.AppContext</value>


</property>

</object>

// C# code:

string msg =
ctx.GetMessage
("HelloMessage", new object[] {"Mr.",


"Anderson"},CultureInfo.CurrentCulture );

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ApplicationContexts cont‘d

•
Spring.NET application containers automatically register event
publishers and send events to detected known subscribers

•
Event reception by implementing
IApplicationListerener

interface

•
Container itself also might send events such as when closing a
context. Example code (lot of details omitted):

IApplicationContext ctx = ContextRegistry.GetContext();

MyEventPublisher publisher =
(MyEventPublisher)ctx.GetObject("MyEventPublisher");

ctx.PublishEvents( publisher );

MyEventSubscriber subscriber =
(MyEventSubscriber)ctx.GetObject("MyEventSubscriber");

ctx.Subscribe( subscriber, typeof(MyEventPublisher) );

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Spring.NET AOP

•
One of the key components of Spring.NET

•
AOP Concepts:

•
Aspect: modularized cross
-
cutting concern applicable to multiple objects

•
Joinpoint: Execution point of a program such as a method invocation or
exception being thrown

•
Advice: aspect to be conducted when program is at a specific joinpoint.
Such as „before method

o.m()

is executed write information to log“

•
Pointcut: set of joinpoints specifying when advice should be executed

•
Advisor: pair consisting of pointcut plus advice

•
Introduction: Using Spring.NET AOP to mix
-
in functionality to objects

•
Target / advised object: object where joinpoint is contained and which
gets proxied by Spring.NET AOP

•
AOP Proxy: Dynamic procy created by Spring.NET including advice and
delegating to advised object

•
Weaving: process to produce an advised object


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General Design Principle

IApplicationInterface

IApplication
Interface

AOP Proxy

Client

IProxyInterface

Advised
Object

Advice

Advice

Advice

1.
Client retrieves application interface from proxy

2.
Client invoked method on application interface

3.
Proxy executes (chain of) advises on joinpoints and
delegates invocation to advised object

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Motivating Example

•
Here is a command pattern implementation:







•
We‘d like to log each call to the
Execute()

method on the
console without touching our source code using an advice:







public interface ICommand {


void Execute();

}

public class ServiceCommand : ICommand {


public void Execute() {



Console.Out.WriteLine("Service implementation...");


}

}

public class
ConsoleLoggingAroundAdvice : IMethodInterceptor

{



public object Invoke(IMethodInvocation invocation) {



Console.Out.WriteLine(“calling method..."); ¶



object retv = invocation.Proceed(); ∙ ¸



Console.Out.WriteLine(“method returned " + retv); ¹



return retv; º


}

}

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Motivating Example cont‘d

•
We have to tell Spring.NET about this intent:











•
Object gets proxied

<object id="consoleLoggingAroundAdvice"


type="Spring.Examples.AopQuickStart.ConsoleLoggingAroundAdvice"/>


<object id="myServiceObject“
type="
Spring.Aop.Framework.ProxyFactoryObject
">


<property name="target">


<object id="myServiceObjectTarget"


type="Spring.Examples.AopQuickStart.ServiceCommand"/>


</property>


<property name="interceptorNames">


<list>


<value>consoleLoggingAroundAdvice</value>


</list>


</property>

</object>

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Motivating Example cont‘d

•
Now we can use advised object. Note, that actually we get the
proxy not the target object:

ICommand command = (ICommand) ctx["myServiceObject"];

command.Execute();

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Spring.NET AOP Fundamentals

•
Pointcuts implement
IPointCut
:











•
Static and dynamic pointcuts (
IsRuntime==true
) possible

•
Dynamic pointcut example: control flow pointcut

public interface IPointcut {


ITypeFilter TypeFilter { get; }


IMethodMatcher MethodMatcher { get; }

}

// Does type match?

public interface ITypeFilter {


bool Matches(Type type);

}

// does method match?

public interface IMethodMatcher {


bool IsRuntime { get; }


bool Matches(MethodInfo method, Type targetType);


bool Matches(MethodInfo method, Type targetType, object[] args);

}

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Pointcuts

•
Pointcut operations: union, intersection

•
Regular Expression Pointcut (methods starting with set..):







•
Attribute Pointcut (all methods with a specific attribute):

<object id="settersAndAbsquatulatePointcut"


type="Spring.Aop.Support.
SdkRegexpMethodPointcut
, Spring.Aop">


<property name="
patterns
">



<list>




<value>.*set.*</value>




<value>.*absquatulate</value>



</list>


</property>

</object>

<object id="cachePointcut"


type="Spring.Aop.Support.
AttributeMatchMethodPointcut
, Spring.Aop">


<property name="Attribute" value="Spring.Attributes.
CacheAttribute
,


Spring.Core"/>

</object>

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Pointcut Superclass

•
Static Method Matcher:





•
You may inherit from this class to implement your own
pointcuts

•
By the way, in the case you are wondering: In our introduction
we used the default
TruePointcut

which maches for
everything


public class TestStaticPointcut :
StaticMethodMatcherPointcut

{


public override bool Matches(MethodInfo method, Type targetType) {



// return true if custom criteria match


}

}

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Advisors

•
Advisors combine a pointcut with an advice

•
Regular Expression Advisor:









•
Attribute Advisor:

<object id="settersAndAbsquatulateAdvisor"


type="Spring.Aop.Support.RegexpMethodPointcutAdvisor, Spring.Aop">


<property name="
advice
">



<ref local="objectNameOfAopAllianceInterceptor"/>


</property>


<
property name="patterns">



<list>




<value>.*set.*</value>




<value>.*absquatulate</value>



</list>


</property>

</object>

<object id="AspNetCacheAdvice"
type="Spring.Aop.Support.
AttributeMatchMethodPointcutAdvisor
, Spring.Aop">


<property name="advice">


<object type="Aspect.AspNetCacheAdvice, Aspect"/>


</property>


<property name="attribute" value="Framework.AspNetCacheAttribute, Framework" />

</object>

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Advices

•
Advices lifecycle per
-
class or per
-
instance

•
Interception Around Advice







•
Intercepts method invocation

•
Code must call
Proceed()

to delegate invocation to advised
object

public class DebugInterceptor :
IMethodInterceptor

{


public object Invoke(IMethodInvocation invocation) {



Console.WriteLine("Before: invocation=[{0}]", invocation);



object rval =
invocation.Proceed();



Console.WriteLine("Invocation returned");



return rval;


}

}

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Advices cont‘d

•
Before advice only called before actual method invocation:








•
Example counts number of calls

•
Method
Before()

is only method within
IMethodBeforeAdvice

public class CountingBeforeAdvice :
IMethodBeforeAdvice

{


private int count;


public void Before(MethodInfo method, object[] args, object


target) {



++count;


}


public int Count {



get { return count; }


}

}

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Advices cont‘d

•
After Returning Advice fires after method invocation








•
Example counts number of calls

•
Method
AfterReturning()

is only method within
IAfterReturningAdvice



public class CountingAfterReturningAdvice :
IAfterReturningAdvice

{


private int count;


public void AfterReturning(object returnValue, MethodBase m,



object[] args, object target) {



++count;


}


public int Count {



get { return count; }


}

}

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Advices cont‘d

•
After Throws Advice handles exceptions





•
Method must have the following form:



•
Note:
IThrowsAdvice

is just an empty marker interface

•
Same implementation class may contain several
AfterThrowing

methods

public class RemoteThrowsAdvice :
IThrowsAdvice

{


public void AfterThrowing(RemotingException ex) {



// Do something with remoting exception


}

}

AfterThrowing([MethodInfo method, Object[] args, Object target],
Exception subclass)

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Introductions

•
Introductions used to add interfaces to existing objects

•
Interface to be added:





•
Implementation class:






public interface IAuditable {


DateTime LastModifiedDate {



get;



set;


}

}

public class AuditableMixin : IAuditable {


private DateTime date;


public AuditableMixin() {



date = new DateTime();


}


public DateTime LastModifiedDate {



get { return date; }



set { date = value; }


}

}

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Introductions cont‘d

•
Now, we can implement an advisor:





•
Which applies the mixin on all objects. We might have
constrained the set of objects

public class AuditableAdvisor : DefaultIntroductionAdvisor

{


public AuditableAdvisor() : base(new AuditableMixin())


{


}

}

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46

Using
ProxyFactoryObject

•
ProxyFactoryObject


•
Basic way to create AOP Proxy

•
Required if you need control over ordering and application of pointcuts
and advices

•
Implements
IFactoryObject

•
Benefit of using such a factory: advices and pointcuts can be
managed by container

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Example for
ProxyFactoryObject

•
Proxy is returned that implements
IPerson
:

<object id="personTarget" type="MyCompany.MyApp.Person, MyCompany">


<property name="name" value="Tony"/>


<property name="age" value="51"/>

</object>

<object id="myCustomInterceptor"

type="MyCompany.MyApp.MyCustomInterceptor, MyCompany">


<property name="customProperty" value="configuration string"/>

</object>

<object id="debugInterceptor" type="Spring.Aop.Advice.DebugAdvice,
Spring.Aop">

</object>

<object id="person" type="Spring.Aop.Framework.ProxyFactoryObject,


Spring.Aop">


<property name="proxyInterfaces"


value="MyCompany.MyApp.IPerson"/>


<property name="target" ref="personTarget"/>


<property name="interceptorNames">



<list>




<value>debugInterceptor</value>




<value>myCustomInterceptor</value>



</list>


</property>

</object>

Interfaces


exported

Advised


object

Applied advices

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Advanced Topics: Spring.Services

•
Spring.Services used with .NET Remoting, Enterprise Services,
Web services

•
Allows to export PONOs (Plain Old .NET Objects) as COM+
objects, Web services, Remoting Objects

•
Allows to use dependency injection for these entities

•
Allows to use AOP for these entities

•
Example .NET Remoting:

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Advanced Topics: Spring.Web

•
Spring.Web provides dependency injection to Web pages and
user and standard controls

•
It also supports bidirectional data binding between controls on
a form and a model

•
Bidirectional means that data can be stored from controls to model on
postbacks, and controls can be initialized from models

•
It supports localization

•
Spring.Web also externalizes flow control instead of using
Response.Redirect

and
Server.Transfer

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Advanced Topics: Spring.Data and Spring.ORM

•
Spring supports Transaction Management

•
DAO pattern for using NHibernate, iBatis.NET, ADO.NET

•
Should arrive soon. No support in version I was able to test

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Further Ingredients of Spring.NET

•
Threading and Concurrency Support following Doug Lea:
ISync
,
SyncHolder
,
Latch
,
Semaphore

•
Object Pooling Support

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Installation 101

•
Installation is simple:

•
First obtain new version of Spring.NET from
http://www.springframework.net/

(I’ve used v1.1 Preview 2)

•
Install .msi file

•
After installation you‘ll find a new entry in programs list

•
Read the online reference document at
http://www.springframework.net/doc/reference/html/index.html

(or the locally installed documents)

•
Spring.NET assemblies available in
<YourDrive>:
\
Program Files
\
Spring.NET
\
Spring.NET 1.1
Preview 2
\
bin
\
net
\
1.1
\
{debug|release}
\
*.dll

•
Additional support libraries in corresponding lib paths

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Roadmap (taken from a presentation by Mark Pollack,

•
Spring 1.1 PR3 Release

•
Framework for WinForms/SmartClient applications 1.2

•
Integration withEnterprise Library (Security, Cryptography,
etc..)

•
ATLAS Integration

•
TIBCO Messaging (RV/EMS)

•
. . . Your requests and contributions . . .

•
Spring.Net.Integration module in CVS

•
“Script” to kick start full project


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Summary



•
Spring now available for .NET
developers. No more reason to be
jealous of Java colleagues

•
Spring.NET represents an important
enhancement to .NET: DI enables your
apps

•
It is not just a naive port of Spring for
Java

•
But, of course, it is subject to
continuous evolution

•
It takes a time to get used to it but then
it makes you more productive

•
My recommendation: try it!

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Resources

•
Documents and installation

•
http://www.springframework.net/

•
Books

•
No special book on Spring.NET around, but I recommend to read the
Java literature

•
Professional Java Development with the Spring Framework

by Rod Johnson,
Juergen Hoeller, Alef Arendsen, Thomas Risberg, Colin Sampaleanu, Wrox
Press, 2005

•
Pro Spring

by Rob Harrop, Jan Machacek, Apress, 2005

•
Articles

•
http://msdn.microsoft.com/msdnmag/issues/05/09/DesignPatterns/



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Q&A





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Thanks for Attending