NFJS Software Symposium Series 2009
Spring 2.5 MVC
Ken Sipe
Technology Director, Perficient (PRFT)

NFJS Software Symposium Series 2009
3.0
Spring 2.5 MVC
Ken Sipe
Technology Director, Perficient (PRFT)

Speaker Qualifications Spring 3.0 MVC
SOA/Enterprise Architect

Developer (Java, C++, C#, Objective-C)

Instructor (VisiBroker, RUP, OOAD)

Speaker (NFJS, JavaOne, JAX-India)

Involved in Java since 1996

Author (Pro Spring 3.0)

kensipe@gmail.com
kensipe.blogspot.com
http://del.icio.us/kensipe
twitter: kensipe

Agenda Spring 3.0 MVC
Agenda

Spring 3.0 - ADD

 Spring MVC
 From Controller to @Controller
Controller Mapping

URL Mapping

Request Parameters

Model Attributes

Spring Forms

 Summary

Spring 3.0 MVC
Spring 3.0 - ADD
Annotated Driven Development

Introduction to IoC Spring 3.0 MVC
AccountService AccountDAO
Attribute Attribute
Attribute DataSource
Attribute
Operation Attribute
Operation
<<uses>>
Operation Attribute
Operation <<uses>>
5

Introduction to IoC Spring 3.0 MVC
AccountService AccountDAO
Attribute Attribute
Attribute DataSource
Attribute
Operation Attribute
Operation
<<uses>>
Operation Attribute
Operation <<uses>>
service dependency on datasource
5

Introduction to IoC Spring 3.0 MVC
AccountService AccountDAO
Attribute Attribute
Attribute DataSource
Attribute
Operation Attribute
Operation
<<uses>>
Operation Attribute
Operation <<uses>>
<creates>
DAOFactory
Attribute
Attribute
Operation
Operation
dependency simply moves
5

Spring IoC Spring 3.0 MVC
AccountService AccountDAO
Attribute Attribute
Attribute Attribute DataSource
Operation Operation Attribute
<<uses>>
Operation Operation Attribute
<<uses>>
<creates>
ApplicationContext
Attribute
Attribute
Operation
Operation
Client:
6

Spring 3.0 MVC
XML Configuration
7

Types of Injections Spring 3.0 MVC
There are 3 types of dependency

injections in the world
 Constructor
values are injected through the constructor at

object construction
 Setter
object is created, then values are set through each

property setter
 Field
object is created, then the values are (usually)

reflectively set on the field (by passing the setter)
8

Spring 3.0 MVC
Spring Annotations

Spring 3.0 MVC
@Component **

Indicates that a class is a component

 Class is a candidate for auto-detection
 Custom component extensions
@Controller

Specialized Component

Typically used with RequestMapping annotation

 Discussed in section on web mvc
@Repository

Now an extension of @Component

@Service

Intended to be a business service facade


Spring 3.0 MVC
@Autowired

Marks a constructor, field, setter or config method for injection.

 Fields are injected
 After construction
@Autowired(required=false)

@Qualifier

Qualifies a bean for autowiring

 May be customized
@Required

Marks a method as being injection required


Types of Injections Spring 3.0 MVC
Constructor

Setter

Field

12

New Injection Type Spring 3.0 MVC
configuration

method
with any

number of
arguments
13

Spring 3.0 MVC
Spring MVC

Spring Web Spring 3.0 MVC
Spring Web MVC

 foundation for all spring web modules
Spring JavaScript

 ajax support
Spring Web Flow

 framework for stateful interactions
Spring Faces

 JSF support
Spring Portlet

 Portlet jsr-168 and jsr-286 support
15

MVC Overview Spring 3.0 MVC
MVC = Model - View - Controller

 separates:
business

 navigation
 presentation logic
 Improves testability of logic and navigation
16

MVC on the Web Spring 3.0 MVC
Model

 data container
displayed by the view

 manipulated by the controller
 commonly a simple map
View

 typically jsp or xml
Controller

 controlling logic
conjuror of model

 navigation
 validation 17

Spring 3.0 MVC
request request
Dispatcher
Controller
Servlet
navigation
data access
render
DB
access
view jsp
Model
18

Spring MVC Taxonomy Spring 3.0 MVC
DispatcherServlet

 Spring provided front controller
 Controls request routing
Controllers

TIP:
 User created POJO 1. Delegate to service beans
for business logic
 Standard Spring beans 2. handle only navigation
View

 Responsible for rendering a response
19

Core MVC Components Spring 3.0 MVC
ModelAndView

 storesmodel data
 associates a view to the request
can be a view implementation or a logical name

ViewResolver

 Used to map logical view names to view
implementations
HandlerMapping

 Strategy interface
 Used by DispatcherServlet to map requests to
controllers
20

Spring Views Spring 3.0 MVC
Extensive Support

 JSP,Velocity, FreeMarker, JasperReporters
 PDF, Excel
Views are mapped by ViewResolvers

21

Spring View Spring 3.0 MVC
22

Spring Controller Hierarchy Spring 3.0 MVC
23

Spring MVC Old School Spring 3.0 MVC
24

Spring MVC Old School Spring 3.0 MVC
25

Spring MVC Old School - Working with Requests Spring 3.0 MVC
26

Spring 3.0 MVC
DEMO: Spring MVC Old School

Spring 3.0 MVC
From Controller to @Controller
Spring 3 @MVC

Spring MVC Annotations Spring 3.0 MVC
@Controller

Stereotype used to “Controller” of MVC

 Scanned for RequestMappings
@RequestMapping

Annotates a handler method for a request

 Very flexible
@RequestParam

Annotates that a method parameter should be bound to a web request

parameter
SessionAttributes

Marks session attributes that a handler uses


New Controller Issues Spring 3.0 MVC
Doesn’t implement an Interface

 Multiple request mappings
 High degree of flexibility
30

Advantages of Controller Interfaces Spring 3.0 MVC
31

Advantages of Controller Interfaces Spring 3.0 MVC
It looks like your trying
to build a controller
31

Advantages of Controller Interfaces Spring 3.0 MVC
31

A World Without Rules Spring 3.0 MVC
Return Type?

 Parameters?
32

Spring MVC Parameters and Return Types Spring 3.0 MVC
Parameters can be

Request / response / session

WebRequest

InputStream

OutputStream

@RequestParam

+++

Return types

ModelAndView Object

Model Object

Map for exposing model

View Object

String which is a view name

Void… if method wrote the response content directly


Spring MVC Controller Evolution Spring 3.0 MVC
mixed model: standard looking old school controller without
an interface.
34

Spring MVC Controller Evolution Spring 3.0 MVC
refactored method: inject the model, return the view
35

Spring MVC Controller Evolution Spring 3.0 MVC
another refactor: just return the model data, view is assumed through
convention.
36

Spring MVC By Convention Spring 3.0 MVC
Conventions:
hotel = HotelController
GET /hotel/list list = method
View selected
from request
path
Added to
Model
37

Multi-Action Convention Spring 3.0 MVC
/hotel/index
/hotel/show
/hotel/list
38

Parameters Spring 3.0 MVC
/hotel/show?id=42
39

Spring 3.0 MVC
Spring MVC Configurations

URL Autonomy Spring 3.0 MVC
http://<host>:<port>/petclinic/main/owner/show
Web Application/Servlet/Controller/method
41

DispatcherServlet Spring 3.0 MVC
42

DispatcherServlet Spring 3.0 MVC
42

Handler Mappings Spring 3.0 MVC
DefaultAnnotationHandlerMapping

 annotation based - @Controller
SimpleUrlHandlerMapping

 configuration based
 still works with annotations
ControllerClassNameHandlerMapping

UrlFileNameViewController

 views without a controller
43

Mapping by Request Mapping Spring 3.0 MVC
44

Mapping by Controller Spring 3.0 MVC
45

Mapping by Convention Spring 3.0 MVC
46

Spring MVC Tips Spring 3.0 MVC
Favor @Controller

 Convention over configuration
 Group controller logic
47

Controller Class Name Conventions Spring 3.0 MVC
/petclinic/main/owner/show
org...petclinic.Owner
48

Controller Class Name Conventions - Base Package Spring 3.0 MVC
/petclinic/main/patient/owner/show
org...petclinic.Owner
49

Controller Class Name Conventions - Base Package Spring 3.0 MVC
/petclinic/main/patient/owner/show
prefix
org...petclinic.Owner
50

@RequestMapping Spring 3.0 MVC
Order of method selection:

First by request method (GET, POST, PUT,

DELETE)
 Second by parameter presence/absense, or
parameter value
 third by method name
 fourth by URL
51

Method-Relative Request Mapping Spring 3.0 MVC
/owner, /owner/*
GET /owner/form
POST /owner/form
GET /owner/find
GET /owner/find?submit=
52

View Name Conventions Spring 3.0 MVC
Show owner:
GET /owner/show
Add or edit owner:
GET /owner/form
GET /owner/form?id=
POST /owner/form
Search owner:
GET /owner/find
GET /owner/find?submit=
53

Views without Controllers Spring 3.0 MVC
Some views don’t review a controller

/index.htm -> “index”


@RequestParam Spring 3.0 MVC
type conversion
optional request parameter
TIP: for optional parameters use objects
GET /owner/show?submit=2
55

@PathVariable - RESTFUL Spring 3.0 MVC
GET /owner/show/2
56

Add Model Attributes Spring 3.0 MVC
Automatically created on every request

 Implicit Model
57

Adding a Single Model Attribute Spring 3.0 MVC
Implicit Model
@ModelAttribute - customize the name
TIP: If you need more than one model
attribute, take model as a input argument
58

More Crazy Stuff Spring 3.0 MVC
Annotation Access to:

 Headers
 Cookies
59

Working with Session Spring 3.0 MVC
Session Attribute for “pet”
“pet” will be added to session
“pet” will be removed from
session
60

Spring 3.0 MVC
Spring Forms

Model Attributes as Command Objects Spring 3.0 MVC
Bind command object to form
Bind request to command object
62

Submitting Forms Spring 3.0 MVC
63

Model Validation Spring 3.0 MVC
Hibernate Validator

 JSR-303 Bean Validation
64

Validation Checks in Controller Spring 3.0 MVC
65

Spring 3.0 MVC
DEMO: Spring 3.0 MVC

Summary Spring 3.0 MVC
Closing and Q&A

References

Spring Framework: http://www.springsource.com/download/

community?project=Spring%20Framework
Spring Docs: http://www.springsource.org/documentation

Session Source Code: http://groups.google.com/group/codemash

Please fill out the session evaluation

 Ken Sipe – kensipe@gmail.com