JAVA Means DURGASOFT

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Struts
Syllabus:

1. Web Application Development Models

2. Struts Frame Work:-
3. Base Struts Components
4. Front controller
5. Application Controller
6. Inversion Of Controll(Ioc)
7. Data Transfer Object(Dto)/Value Object
8. Struts Initialization
9. Application Development In Eclipse Ide
10.Using Resource Bundile In Struts
11.Applying Programmatic Validation
12.File Uploading In Struts
13.Developing A Struts Application In My Eclipse
14.Adding A Server In Ide
15.Exception Handling In Struts
16.Global-Forwards

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WEB APPLICATION DEVELOPMENT MODELS:--

When designing an app by the developers for the same problem diff developers
provide diff designs. So designs may not be same but they output the app same.

If one developer wants to understand the designs given by another developer then
feel uncomfortable, because the designs may not be I the same way as that
developer expected.

So in order to solve the designing problems and also to inform the developers about
what technology is used at what place, we got web application development models.

We got two models: - 1) models1 and2) model2

MODEL1:- this model introduced along with JSP technology, in this model a JSP is a
responsible to provide all functionality required for a web application may contain
any no. of (or) series of JSP pages in order to provide the functionalities.

JSP1 JSP2 JSP2

Bean DB

1) MVC designe pattern.

2) MVG,MVC2 are architectures .

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The following diagram rep. Models architecture:-

Client JSP

P.L

+- Bean DB

B.L

1) Limitation of Model1:- the application may contain a series of pages an &if any
changes are done in one page then, if need the changes other pages also we call
this problem as a page-centric problem.

Because one page is depends on another, all the pages should be developed by a
simple developer only, it means division of labor is no possible.

Each page is responsible for providing (or) implementing the logics like input
verification, Session management, securityetc. so it increases the size of a JSP
and also burden on the developer this application code we call as redundancy.

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Implementing B.L in a JSP is not in industry standard, because JSP should contain
tags, but not code.

In order to overcome the limitations of model1 we got model2

Client servlet

Req controller Bean DB

Res view model1

MODEL:-2
Client servlet

Req controller set javaBean

DB

Res View jsp get

Model2 (MVC) is the combination of servlet and JSP technology

Actually sun micro system introduced, JSP technology as a replacement for servlet
technology, but industries realize that for the web app development both servlet
and jsp required, and introduced model3 that is MVC architecture.

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In the MVC applications, controller is a servlet, iew is JSP (or) html and javaBean
(or) ejb (or) spring are Model .

Controller is a component , which containes all primary logics required like

sessions and security and also it component an entire flow of an application.

Model component concentrate on business logic of an application.

View component concentrate on presentation.

We call these MVC application also called servlet centric.

In Model2 P.L and B. Logic are separated from each other, so page centric
problem is eliminated.

ADVANTAGES:- Business logic is implemented in javabean. So we can reuse the

same bean component in other web application also.

all logics are separated, so changes from one logic does not effect other logic, it
means we got flexibility.

Because each component contain a specific logic so complexity is reduced.

Division of laboure is possible, because the logics are devided into diff component
, so that application time reduced.

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RULES TO FOLLOW IN MVC:-

1) An application can contain any number view and Model components, but it
contain only single controller
2) Two presentation pages (jsps) can not communicate each other directly if
communicated then we get page centric Problem again.
3) Model and view components can not talk each other. It should be done all
ways through controller as a mediator.
4) Each component should contain, its specific logic. We can not mix multiple
logics in a single component.

Question:-why servlet is a controller?

1) If a jsp used as a controller, then we need to insert java code in jsp. But this is
against industry standard. So jsp is not suitable as a controller.
2) If we use java bean as controller then it cannot receive (or) handle http
request. So bean cannot be used as controller.
3) Finally servelt is suitable for used controller.

Question:- why jsp as view?

1) If we use servlet as view then we need to write presentation logic inside java
code. the second reason is if we modify the presentation logic then we need
reduced play and re compile and restart the server.
2) If javaBean is used as view then it cannot given reponse page.
3) Finally jsp is suitable to use as view, because if any presentation logic is
modified, then it will be automatically effected.
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IMPQUESTION:-Why Bean as a model?

1) If we use servlet as a model then we cannot get middle ware services required
for the business logic.
2) If we use jsp as a model then again we should insert java code in jsp this
against industry standard
3) Finally a Bean component is suitable for implementing business logic of an
application. So it used as model.

PREVIOUS:-

JSP servlet EJB EJB

Session bean Entity Bean DB

View controller

B.L persisentlogic

PRESENT:--

PREVIOUS:-

JSP servlet Spring hibernate

beanDB

View controller

B.L persisentlog

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STRUTS FRAME WORK:-

WHAT IS FRAME WORK?

1) Every system (i.e pc) will follow some commonalities. All applications
will accept inputs from key board, produces output on to the screen
and shares a common memory.
2) The above concept is the foundation per the development of the
frame work.
3) A frame work contain set of libraries (or) classes. Each library will
provide a basic foundation for the development of an application.
4) We can define a framework as, it is a software, provides reusable
components with basic functionality and the makes an application
development faster and easyer.
5) A framework will provide an abstraction layer and allowes the
programmer to develop their application as faster and reduces
burden on the developers.

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COMMON FUNCTIONALITY (OR) PRINCIPLE OF FRAMEWORK:-

Every frame work will follow a standard notation it is an application

contains one (or) more central configuration files and these files are
loaded into an application, so that an high level object is generated and
this object is responsible for maintaining an entire application

For example, in case of struts, we write struts configuration files, which

are loaded into an application and produces Action servlet object this
object maintaine struts application.

The same rule applicable for all frameworks like spring, hibernateetc.

STRUTS:-

Struts Appln ActionServlet

Configurationfile

SPRING:-

SPRING Appln BeanFactory

Configurationfile

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q) what is struts?

Struts is an open source framework given by Apache software

foundation(ASF) , under one of its project is called jakarla project

Struts is a frame work , used to develop web applications for java using
mvc2 , architecture.

Jakarta project provided two sub projects.

1) Commons.
2) Struts.

Commons projects is having approximately 30s of projects like logging

collections, dbcpo. Etc.

Struts provided two sub projects inside it, those are validation and files.

Validation and files:-

Jakarta

Commons

Logging

Collection

Dbcp

Io

Struts

Validation

Tiles
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We can define struts frame work also as an implementation of MVC2

archetecture of JSP.

Types of frameworks:--

Literarly (or) generally frame work are devided into two types

1) Invasive
2) Non-invasive

Invasive frame work means it will force the programmer to create their
classes by extending (or) implementing their classes from predefined
classes (or) interfaces.

Non-invasive frame work means, it does not force the programmers to

extends (or) implement their classes from any predefined classes (or)
interfaces given by that frame works.

For example, struts is an invasive frame work and hibernate and spring
are non-invasive frame work.

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Strutscalanahanmay-2004 introduced.

Hibernate-> gavinking jbass server also developed

Spring rod Johnson interface21

1) Validation
2) I 18n(internationalization)

q) why struts is so popular?

Because of the following two reasons.

Struts support extensive validation, where no other frame work can

support.

Struts is having inbuild support for I 18N

Struts frame work is provided the following 3 categories of caomponents

for struts programmers (or) developers, inorder to develop web
application using these component

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1) Base frame work

2) Jsp tag library
3) Internal frame works

Base frame work provides many struts components used for

implementing same logic fr struts app.

Jsp tag libries are the given for the development view component
either for accepting input (or) produce o/p.

Internal frame works:- are validation frame work and files frame
works these frame will add additional capabilities to a struts
application.

Note:- struts frame works is capable to integrate with any after frame
works, that is available in the market today(or) even that is going to
come tomorrow.

Base struts components:-

Action Servlet:- it is heart of struts app.

It is controller

It is entry(or) exit and control the entire apP

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C1 req actionservlet login

Ft

C2 req Remove

Strutsconfig.xml

P c Actionservlet extends. Hhp servlet

Iq) servlets implements only one ways that is implementing servlet

interface.

Actionservlet taking help from request processer class.

Public class AS extends HHP

Public void init(sc)

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Object of RP;

Initialize

P v doet()

Process()

P v do post()

Process of RP

Action from component:-

To store the input values at server

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Public class loginform extends A.F

Setter and getter and some validation methods.

Base components of struts:-

Action servlet:-this component is the front controller of a struts

application.

In a struts application every request enters into a struts application and

every response from a struts app will be traveld through this component
only.

This component is acting as entry point for the request and exit point for
the request.

The entire flow of a struts application will be managed by this component

only.

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Action servlet is only one servlet component that exits in a struts

application, we can either use this class directly in our instated of using
this class.

This component will get the flow details of an application through a struts
configuration file.

This class is extends from HHPservlet and it has implementation of init(),

decret(),dopost() and destroyer.

Note:--Actionally action servlet does not maintain the flow off an

application it takes help of another component internally called request
processor. This class is said to be an application controller.

When a servlet is an acting as front controller o client will be send a

request to the servlet directly. the servlet only received that request while
it is travelling. So per a front controller servlet, we can not use exact
match url pattern either we should use extension mach (or) directory
match.

2)Actionform:- this component is also called a formBean.

This component is used to store the input vales given by a client at a client
side, on the input values in this component only.

We call action from as a bean and it is reusable.

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In order to store input values given by a client, we need some properties

and the request parameter names and the property names, both must be
same.

We can not use directly actionBean class. We need to create a derived

class struts class by extending actionform.

3)Action:- action class containe logic action classis a place, where we

implement business logic (or) wrapper around b.logic (integration logic)

If an app need every small b.logic then we implement it inside action class
only and if complex b.logics are required then we will communicate the
outside model components like, ejb, spring..etc from action class.

Action class is a place from the control goes out of struts frameworks to
out side model and the action class place in to where the control comes
back to the struts frame work

Action class is not a servlet but followes servlet model. It means single
instance and multiple threads model.

While developing real time applications, we should not write b.logic

implementation in action classs because the action class will not get the

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real time services like transaction and security from the container
automatically.

In case of real time app action class access mediator to call the b.logic
implemented at out side model componenets.

By default action class is not thread safe but it is possible to convert action
class into thread safe, by applying synchronization mechanism.

4)ActionForward:- this component containes a string value, by depending

on which a view is selected by the controller(Action servlet)

Actionforward object will be transferred from action class back to

actionservlet aftet b.logic is executions is completed.

5)Actionmapping:-this component is dynamically constructed and it

containes in formation about an actionform an action class and resulting
views (like success)

Internally actionservlet communicate will actionmapping object to get

these details, whenever a request is given.

Configuring actionservlet:- action servlet is a servlet, so we need

configuration it in web.xml

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We need inform the container that an object of this class should be

created . before any request is given, so we need include <load-on-
startup-value>

In struts application , except this action servlet all the remaining

component need to be configured in struts configuration file.

Actionservlet loads struts.configuration file as an initparameter to the

servlet.

<servlet>

<servlet.name>action</->

<servlet-class org.apache.struts.action.actionservlet<-

<load-on-startup>/

<init-param>

<param-name>config</>

<param-value>/WEB-INF/struts.config.xml</-

</init-param>

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</servlet>

<servlet.mapping>

<servlet-name>action</servlet-name>

<url-pattern>*.do</url.>

</jer-mapping>

</web-app>

Struts.config.xml

Client A.S loginAction

view
Login form

Input.jsp

Customer id cid

Customername cname

Customeraddress cadd

Sond

Public class customerform extends actions

Cidd, cname,cadd

Setters&getters
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Reset()

Validate()

Reset method is used for before sending the data the default values are
assinge.

Scope=request if client request to time then only object action class

objects created only one object is only perclient.

i.q) configuring (and) creating action form

1) actionform objects in struts is for starting client input and then to apply
validation on the given input.

2) in action form class we create properties, in order to store input values

and the request parameter names and property names in the form bean
class, both must be same.

3) in a form bean class, we include the following 4 methods. For storing

and validating the input.
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1)setter methods.

2) getter methods.

3) reset method

4) validate method.

4) reset method is used to initialize(or) reset the bean properties with

default values, before storing the new values in to the variables.

Validate method is apply validation on the user input.

i.q) action form object will be created by the controller servlet (or) A.S and
by default

this object will be stored in session scope. It means form bean object per
each client session.

If we want a formbean object per each request then we need to modify

its scope from session to request.

In struts frame works , we have totally the following 6 types of

actionform.

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1) Org.apache.struts.actionform.
2) Org.apache.struts.action.dynaactionform.
3) Org.apache.struts.validator.validatorform
4) Org.apache.struts.validator.dynavalidatorform
5) Org.apache.struts.validator.validatorActionform
6) Org.apache.struts.validator.dynavalidatorActionform

The following is an example of actionform.

Public class loginform extends actionform

Private string uname,pwd;

Setters

Getters

Public void reset(Actionmapping mapping,httpservletrequest req)

Public actionerrors validate(Actionnmapping mapping,httpservletrequest

req)

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Row to work strut-config.xml:-

<strut-config>

<form-beans>

<form-beanname=frm1type=loginform/>

</form-beanss>

</struts-config>

Note:- we need configure formBean in struts configuration file the struts

configuration file name can be <any name> .xml.in general we provide the
name as struts-config.xml the following example represents configuration
of formbean in strutcon-figurationfle.

<strut-config>

<form-beans>
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<form-bean name=frm1 type=loginform/>

</form-beans>

</strut-config>

Note :- the elementformBeans> must be immediately after root the

element <strut-config>. It means we can not include any other elements In
b/w them.

Creating and configuration an action:-

Action clas is a place where we insert either b.logic (or) integration logic.

Inside actionclass the only method, in which are we should implement our
logic is execute().

After logic is executed it resume an actionformword object back to

actionservlet.

By depending on actionforward object one view is selected along multiple

views.

Example:- public class loginaction extendaction

Public actionforward execute(actionmapping mapping)

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Actionform form, httpservletRequest req, hhpservletresponse res)

Throws exception

--

--

If(---)

Return mapping find forward(success);

Else

Return mapping.find forward(failure);

Each action class of struts should be configure in struts configuration file.

All action classes must be configured under-action mapping element.

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While configuring an action, we should include its <forward> elements

also.

Example:-struts-config.xml

<s-c>

<formBeans>

<action-mapping>

<actionpath=/login name=frm1 type=loginaction>

<forward name=success path=/success.jsp/>

<forward name=failure path=/failue.jsp/>

</action></action-mapping>

</s-c>

How to make your class as singleton:-

Public class sample

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Private stafic Boolean

Public sample()

If(flag)

Flag=true;

Else

Throw new exception();

Finally this class allowes only one object then it is a singleton.

Note:- Design pattern used in struts:-

Singleton:-if a class allowes as to create only one object then that class is
said to be a singleton class.
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In struts p.work, actionservlet is a singleton class

The struts framework developers explicitly made actionservlet class as

singleton

If we want make a java class as singleton then it is possible in two

approaches.

1)by throwing an exception , when typing to create more than one object

2)by creating a private constructed a factory method.

Example:- public class sample

Private static sample s1=new sample();

Private sample()

Public static geetinnstance()

{
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Returns;

Static methods are allowed.

Static variables and static methods

Static methods can not allow super,this key works.

Sample ob1=sample .getinstance()

Sample ob2=sample.getinstance()

In the above code ob1 and ob2 will containe same objects which means
ob1==ob2 simple address same. With two objects are equal to==then we
say that both are rep single object.

I.Q):what is the diff an ordinary servlet and an action servlet?

In same cases an ordinary servlet may not be singleton, in all cases

actionservlet is singleton.

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The reason is , inn case of an ordinary servlet a web container will make it
as singleton. But in case of actionservlet, this strutsframework developers
only madeit as singleton.

I.Q):how to make a java class as imuutable?

We need to follow the rules.

1) Create only private, final variables in the class.

2) Create a parameterized constructor.
3) Only implement getterr methods in the class, without setter
methods.

Frontcontroller:-while developing MVc based web application centerlized

common logics into one component is possible through front controller.

If no front controller is used then the common logics are de centerlized ,

so that we will get duplication of the logics. When developing struts
applications, we need a front controller servlet and it is an actionservlet
and it is singleton class.

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C1---req request params

Validation

Session one.jsp
presentation

c2----req request params

validation

session

presentation

C1---req request params one.jsp

Validation presentation

C2req Session presentation

Two.jsp

Application controller :-

An helper component of front controller is called an application controller.

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In an MVc based applications, there exists a separate application

controller component per each module but only one front controller will
exits for all module.

While developing MVc based applications, it may containe more than one
module. So if there is only frontcontroller then the front controller has to
maintaine the entire flow. It becomes complex.

So, in order to reduce the burden on frontcontroller each module flow will
be maintained controller are maintained by frontcontroller.

In an MVc application, there can be any number of application controller,

but there must be a single frontcontroller.

INVERSION OF CONTROLL(IOC):-

Separation an implementation of an object from how that object is

created is called IOC.

The constructing of an object will be taken care by an external entity and

the programmer who created the class, does not any knowledge of
creating object of for it.

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Inverting the control means redirecting the object construction from a

programmer to an external person in ioc, we have two categories.

1) Dependency lookup
2) Dependency injection

When working with struts framework, we have both lookup and

injecting in the application.

In case of lookup, if a first object is depending on second object then

the first object should be get the explicitly by second object.

In case of injection if a first object is depending an second object, then

while creating first object, automatically second object is inserted, by
the external person who is creating the first object.

In struts frameworks action class object depends on actionforrm object

and actionform object is automatically injected into actionclass, so this
is a dependency injection mechanism .

In lookup mechanism, explicitly one object with get the other object.
Mostly this lookup we are going to observer when struts communicate
with ejb

Data transfer object(dto)/value object:-

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When developing apps for realtime, it may contain multiple modules

(or) layers and data transfer is required from one layer to another layer.

If we transfer individual values from one layer to another layer it

increases no.of round trips b/w the layer and automatically he
performance of application will be decreased.

In order to overcome the above problems, instated of sending

individual values, store all the value into an object and then transfer at
time all the values, by transferring that object this pattern will call as a
DTO pattern.

In struts framework, Actionform is an object stores input values and

transfer these values to the business layer(Action class), in the form of
an object. So an Actionform object is a DTO in struts.

I.Q)Note:- the common design pattern used by all java applications (or)
projects is DTO.

Struts instalization:-www.struts.org.apach

Struts framework is not a setup file to install in a system.

All frameworks are not installable software.

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Working with struts framework means, adding jar files into the lib
folder of our application and adding the jar files required at the class
path.

Visit struts.apache.org and down loade struts-versions-all-zip.

Unzip the above zip file and take struts-blank-version.war fro apps
folder.

Copy the above war file into a newly created folder and extract the war
file by using jartool.

jar xvf struts-blank-version-war

under WEB-INF/lib folder, we will get the jar files related to struts
framework.

Into our web app, we need add these jar files into lib folder.

Note:-the best version of struts is struts-1.3.8

Example:- the following example is based on MVc model and the example
is creating for our front controller servlet.

The frontcontroller servlet maintaice the flow of the application.

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Login.html C fc servlets sample1

Center name satya.do handle1()

Submit

Product.html sample2m

Enter product id handle2()

Submit

Result res {success.jsp}

{0r)

{failures.jsp}- view.

Directory structure:-

fcExample

WEB-INF

Web.xml

Classes

Fcservlet

Sample.java

Sample.java

*.classes

login.html

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product.html

success.jsp

failure.java

i.q):- which collection is best one in collection

hashmap() object

map m1new hashmap();

m.put(/sathya.do,newsample())

m.put(/product,newsample());

instance of operator duty is check the condition

login.html:-

<center>

<formaction=sathya.do>

Entername:<inputtype=textname=t1><br>

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<input type=submit value=click>

</form>

</center>

Product.html:-

<center>

<form action=prod.do>

Enter productid=<input type=text name=p1><br>

<input type=submit value=click>

</form>

</centr>

Web.xml:-

<web-app>

<servlet>

<servlet.name>frontcontroller</

<servlet-class>fcservlet</s.>

<load-on-startup>1<1>

</servlet>

<s.m>

<or>*.do>

<15-m>
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</web-app>

Fcservlet.java:-

Import java*.servlet*;

Import java.io

Import java.urtil.*;

Public class fcservlet extends Httpservlet

Map m;

Public void init(servletconfig sc) throws servlet exceptions

M=new hashmap();

m.put(/sathya.do, new sample1());

m.put(prod.do,new sample2());
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Public void abcret(htt req, res) throw SI,IOE

String result;

String rpath=req.get.servletpath();

Objecto=m.get(r.path);

If(o instance of sample1)

Sample1 s1=(sample1)o;

Result=s1 handle1(req,res);

Else{

Sample2 s2=(sample2)o;

Result=s2.handle2(req,res);

Request is pather rd=req.getrequestispather(t1);

Rd.forward(req.res);

Sample1.java:-
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Import javax.servlet.http.x;

Public class sample1

Public string handler(htt res(). H res)

String str=req.getparameter(t1);

If(str.equals(satya));

Returnsuccess

Else

Return failure;

Sample.java

Import

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Public class sample2

Public string handle2(m req hres)

String str=req.getparameter(p1);

If(str.equals(p123))

Return success;

Else

Return failure;

Servlet api.jar will provide tomcat server.

Ant also deployment.

Context path is nothing but application name

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Success.jsp:-

<%out.println(<h1>success</h1>);

%>

Failure.jsp:-

<%out.println(<h1>failure</h1>);

NOTE:- in the above example, in Fcservlet class, we used hashmap object

for storing the flow details.

Hashmap object is the best collection in java collection api

In the Fcservlet class, we used instanceof operator, its perpouse is to

know whether a particular object belongs to a particular class type (or) not
if ok it returns true other wise it returns. False

Note:- this instance of operator is mostly used in java messaging service

(5mb)

If we want compile the above servlet and both sample1 and sample2

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classes ten we need to set seervlet api.java

%classpath% rep old value of class path.

Deploye appc:toncats.s/webaps folder

Start the server

Open the browser ad send request.

http://localhash:Rov/Fcexample/logic.html

finally in the above example we have a controller, two model component

and 4 presentation pages. So this is an example related to mvc model.

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Login.jsp web.xml struts.config.xml

Username web actionservlet actionforwardobj loginaction

Password container

Submit login form

Success.jsp

res (or)

Failure.jsp

struts.config.xml:-

<s-c>

<form-beans>

<form-bean name=f1 type=loginform/>

</form-beans>

<action mapping>

<action path=/check name=f1 type=loginaction>

<forward name=success path=/success.jsp>

<forward name=failure path=/failure.jsp>

</action>

</action.mappinng>
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</s-c>

1) When a client request is given, a web container receives the request,

because the request is given for a active resource dynamic.
2) Web container reads web.xml(DDF) and identifies a servlet suitable
for the given request.
3) The container identified that actionservlet is suitable to receive this
request and then transfer the contain to the actionservlet.
4) Actionser vlet reads struts configuration file.
5) Actonservlet verifies whether the given request path is matching
with an actionpath(or) not
6) If action path matches then the controller servlet verifies whether
logical name of action and logical names of formbean, both are
equal(or) match.

7) If names are equal then the controller servlet first creates

actionfor(logicalform)ed then the controller servlet
8) After form bean executed actionclass. In action class execute() will
be called.
9) If comple b.logic required then control is moved to the outside
model component.

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10) Persistence logic is also a part of b.logic . so the model component is

communicate with db.
11) The model component returns control along with result back to
action class.
12) Execute() method of action class returns actionforward object back
to actionservlet.
13) Actionservlet again reds struts configuration file and verifies a
suitable forward. Per the returned int value (or) object.
14) Action servlet selects an appropriate view component
15) Finally action servlet uses request distachers forward mechanism
and forward a suitable view as a response back to the client browser for
the given request.
Note:-activally actionservlet doesnot perform this entire flow
management internally actionservlet takes help of request processor
class, to do this entire flow management for a given request.
Example:- the following example is a login application using struts
framework.

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Loginapp
Src
Loginform.java
Loginaction.java

WEB.INF
WEB.XML
STRUTS.CONFIG.XML
CLASSES
LIB
*.JAR

LOGIN.JSP
SUCCESS.JSP
FAILURE.JSP
<init-params>
<p-n>config</p-n>
<p-v>/<WEB-INF/classes/struts.config.xml<p-v>
</init-params>
Application development in eclipse IDE:-
Step1:-start eclipse ide dbl click on eclipse.exe from eclipse folder and
enter same work space nameok
Step2:-click on file menu new project javaprojectnext enter
projectname if version is change(select version)(loginapp) nextfinish
Step3:- RT click o WEB-INF newfolderenter folder name as
classes. Similarly lib folder also
Note:-to shift (or) transfer from package explorer to navigator ,click an
windowmenushow viewnavigator.

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Struts provided same predefined tags those tags we can use the JSP pages
Step5:-click an
projectnamenewfileenterfilename(login.jsp)finish
<!login.jsp---
%@taglib uri=http://struts.apache.org/tag-html prefix=html%
<html:form action=login.do>
Username:<html:text property=uname/><br>
Password:<html:password property=pwd/><lrr>
<html:submit value=chick/>
</html:form>
Struts html.tld no need write from struts words.
Note:- while creating the above jsp, we used html tags given by struts
framework. The reason is , when we submit the request then immediately
these input values will be stored automatically in a framebean object.

2)if we use ordinary html tags in jsp then the input values will not be
stored in a formbean object

3)to use these html tags provided by struts, we need to add a standard uri
and prefox in our jsp

<!success-jsp---this components can be same html,xml,jsp-

<%out.println(<h1>login success</h1>);

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Failure.jsp:-<%out.println(<h1>failure</h1>); %>

Step6:-RT click on project namepropertiesselect java build path at

leftsideselect source tab at rightsideselect project name-
>removeadd folder select srcokclick on browser button select
classesokselect libraries tab click on add external jars button
select two jar files.

1) Struts-core-1.3.8-jar
2) Servlet-api.jarok

Step7:-RT click on src newclasses enter class name super class

name(Action form) finish.
LOGIN FORM.JAVA:- import org.apache.struts.action.actionform;
Public class loginform extends actionform
{
Private string uname,pwd;
Public string getpwdu{
Return pwd;
}

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Public void setpwd(string pwd)

{
This.pwd=pwd;
}
Public string getname()
Return uname;
}
Public void setuname (string uname){
This.uname= uname;
}
}

STEP 8:- RT click on srcnewclassname(login action)-

>superclassname(org.apache.strutsaction.action)finish
//loginaction.java:
Import javax.servlet.http.httpservletRequest;
Lmport org.apache.struts.action.action;
Import org.apache.struts.action.actionmapping;
Public class loginAction extends action
{
Public actionFordward execute(Actionmapping mapping)

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Actionform form, htt req,htt res) throws exception

{
Loginform lf=(loginform) form;
String s1= lf.getname()
String s2= lf.getpwd()
Actionforward of= null;
If(s1.ewab(satya) && s2.equab(satya))
{
Af= mapping.findward(success);
}
Else
{
Af=mapping.figforward(failure);
}
Return of
}
}

STEP 9:- RT click on WEB-INFnewfile(web.xml)finish

< !=- web.xml
<web-app>
<servlet>
<servlet-name>action</->

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<servlet-class>org.apache.struts.action.Actionservlet</->
<load-on-startup>1</
<init-param>
<param-name> config</param-name>
<param-value>/WEB-INF/struts-config-xml<1->
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>action</->
<url-pattern>*.do</->
</serv-mapping>
</web-app>
STEP:- RT click on web-inf newfile enter filenamestruts-
config.xml)ok
Copy the DTD in the existing project.
</DOCTYPE

---1-3>

<struts-config>

<form-beans>
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<form-bean name= frm1 type=login form/>

</form-beans>

<action-mapping>

<action path=/login name=frm1 type=loginAction>

<forward name=success path=/success.jsp/>

<forward name=failure path=/failure.jsp/>

</action>

</action-mapping>

</struts-config>

STEP :- copy struts jar file into lib folder of our web application. Because
container does not know about the struts fws that way we inform the
tomcat by processing some jar files.

Tomcat know about only jsp and servlet.

USING RESOURCE BUNDILE IN STRUTS:-

1)in a struts application, we use resource bundle, in order to get lables(or)

error messages.

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2) in a resource bundle, the data should be stored in the form of key value
pairs, where both key and values are used defined.

3) while creating a jsp, instated of manually typing lables, we can get them
from a resourcebundle.

4) while applying validations. On the user input in a form bean class, if a

validation fails, then the error message must be taken from the resource
bundle only.

5)while creating input jsp pages, if we want to get lables from a resource
bundle, then we need to use<bean:message>

The bean tags are provided by struts fw in a told file called struts-bean-tld.

If we want use bean tags in our jsp then we need the following taglib
directive in our jsp.

<%taglib uri=http://struts.apache.org/tags.beanprefix=bean%>

For example we want to get a lable from username from a resourcebundle

then we need the following tag.

<bean:message key=input.user/>

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When we use resourcebundle in a struts application then we need to do

the following two things.

1)store the bundle at classes folder.

2)configure the bundle in struts.configuration file.

In struts-config.xml,we need the following element after closing

<action.mapping>

<message-resources parameter-sathya/>

APPLYING PROGRAMATIC VALIDATION:- in a struts application, we can

apply validation on the user input values, either programtically
declaratively

programatically means manual coding get declarative means through

xml.

If we want apply validation on the input then we need to override

validation() in our formbean class.

while applying validation, if any errors are occure then we need to get
error messages from the resource bundle only.

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while validation , if an error is occurred then we need to create an

object of actionmessage class by passing key of the error message.

we need to store all actionmessage class obstructs in to actionerrors

class object.

actionerrors class object stores group of actionmessage class objects

FOR EXAMPLE: public actionerror validate(mapping,req)

Actionerrors errors=new actionerror();

If(uname.length()==0)

Actionmessage am1=new actionmessage(userwrong);

Errors.add(uname,am1);

Return errors;

While executing validation, If any errors occurred then we should get

back againe our input page, to inform about this information, we
should write validate and input attribute to the action element in
struts.configurationfile.
Example: <struts-config>

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--

<action path=/login name=frm1 type=loginactionvalidate=true

input=/login.jsp>

Bydefault false

</action>

In order to display error messages on the browser in our input page, we

should write <html:error/>

NOTE:- while displaying the error messages, we can display either all
errors at one place (or) individual errors for each property separately

if we want display individual errors then we need to pass property

name.

<html : errors property=uname/>

Example:- the following example is for applying validations on the input

values and to use resource bundle in the application.

The following example is an enhancement to the previous applications

only some files need changes and trainings files are used as it is.

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</-login.jsp

<% @ loglib uri=http://struts.apache.org/tags-html/prefix=html%>

<% @ taglib uri=http://strut.apache.org/tags-beam prefix=html %>

<html:form action=logindo>

<bean: message key=input.user/>: <html:text

property=uname/><html:errors property=uname/><hr>

<bean:message key= input.pwd/> :<html:password property

=pwd/><html:errors property=pwd/><br>

<html:submit value=click/>

<html:form>

LOGIN FORM.JAVA:-

Import org.apache.struts.action.actionfrom;

Import org.apache.struts.action.ActionMapping;

Import org.apache.struts.action.ActionMessage;
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Import org.apache.struts.action.ActionErrors;

Import javax.servlet.http.HttpservletRequest;

Public class loginform extends Actionform;

Private string uname,pwd;

Setter & getters.

Public actionerrors validate (ActionMapping mapping, HttpservletRequest

req)

Actionerrors aes= new actionerrors();

If(equals(uname) \\uname.length()==0)

In real time use one condition

ActionMessage am1=new ActionMessage(user.error);

Aes.add(uname,am1);

If(.equals(pwd)|| pwd.length()==0

Actionmessage am1=new actionmessage(pwd.error);

Aes.add(pwd,am2);
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Return aes;

In struts.config.xml, we need the following change and the remaining

configuration is same as previous application.

</action-mappings>

<message-resources parameter=sathya/>

Store the following satya.properties file in the classes folder

#SATHYA.PROPERTIES:-

Input.user=username

Input.pwd=password

User.error=<front color=red>username is required </fat>

Pwd.error=<front color=blue>password is required</font>

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NOTE:-while applying programmatic validation by overriding validate()

then we have the following drawbacks.

1) If the number input values are more then the size of the validate()
will be increased. And it increases the burdon on the programmer.
2) In validate() mostly we duplicate the same logic for multiple fileds.
this increases to data redundancy more input values.
3) In order to over comes the above problem, in struts we can apply
declaration validation.

DYNAACTION FORM:- in actionform, we have the following two mager

draw backs.

1) If presentation jsp page has modified after action form class is

generated . then againe we need to modify our action form. And
after that recompile and redeploye and restarting the server is
required.
2) If the number of presentation (or) input pages more with diff fields
then we need to manually create that many number of actionform
classed it increases the burdon on the programmer.
3) In ofer to overcome the above drawbacks of an actionform, we got
dynaActionform.
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4) dynaActionform is class given in org.apache.struts.action package

and it is extended from actionform.
5) In case of dynaActionform , we does not required create manulate
actionform classes
6) If case of dynactionform, we need to directly configure
dynactionform class is to struts-config file.

For example:- <form-beans>

<form-bean
name=f1type=org.apache.struts.action.dynaActionform>

<form-property name=unametype=java.lang.string/>

<from-property name=pwd type=java.lang.string/>

</form-bean>

</form-beans>

DYNAACTION:- public class dynaActionform extends AF

Private hashmap dynavalues= new hashmap()

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Public void set(string key,object value)

Dynavalues.set(key,value)

Public object get(string eky)

Return dynavalues.get(key); daynavalues

Public map getMap()

Return dynavalues()

Public class login action extends Action

P AF execute(------)

DAF daf=(DAf) from;

Object o1=daf.get(uname);

String u=(string)o1;
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--

--

Collection map

List set queue HashMap storedMap(interface)

DynaActionform is faster than the actionform (slow) because so many

setters & getters.

NOTE :- DyActionform class is going to store input values given by a

client into hash map object.

in DAF class, we do not have setters and getter method for each
property. Instated, we have set and get method

When a form is submitted, internally for each request parameter set()

will be called and it will store the input values into Hashmap object.
Finally Hashmap object is going to containe the input value submitted
by a client.

in action class of our application, we need to call get() of Dyafrom, to

read input values given by a client

in DAF class, another method given called get map() it return the
HashMap object and it containe all input values given by a client in the
form of (key, values) pair.

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the internal source code of DAF. Will look like as follow.

Code:- public class DAF extend AF implements DynaBean.

Private HashMap dynavalues=new HashMap()

Public void set(string key, object value)

Dynavalues. Set(key, value);

Public object get(string key)

Return dynavalues.get(key);

Public Map getMap()

Return dynavalues;

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if we use req then tight coupling is accure. If we change servlet .API

then compulsory change Action class also.

Note:- interface satya

Class java

Nested class

--

--

Durga.java

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Map.entry:- if we use static then it is called nested class.

if we cant use static then it is called inner class.

in the execute method of Action class, we need to type caste

ActionForm object into DyAFrom and then call get() by passing
key(property name); to read the values.

Ex:- public class loginAction extends Action

Public AF execute(----)--------exception

DAF daf=(DAY)form;

Object 01=daf.get(uname);

String u=(string)01;

String p=(string)daf.get(pwd);

--

--

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comparatively DAF provides high performance then ordinary AF.

Because DAF used HashMap provides high performance among also
calculations of java.

DRAWBACK:- if we use DAF then input validations are not possible at

FormBean level.

in this case we need write validations at action class level. But writing
input validation in action level is not good approach.

Note:- if we apply client side validations using java script then we can
eliminate the draw back of dynaActionForm.

i.q:- why cant we use HttpServletRequest object of execute method,

to read input values given by a client.

a) if we use a request object API(methods) then our action class

becomes tightly coupled with servlet API, it means, if servlet API has
modification class also.

In order to provide losse coupling b/w Action class and servlet API, we
do not use request object in the execute() for reading input.

IMPLEMENTING VALIDATION IN ACTION CLASS:-

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In case of DAF, we need to apply serverside validation in execute ()

no of Action class only.
While validating the input, if any errors occure object
(Actionmessage object) into ActionErrors object.
Finally we need to store ActionErrors object into request object. To
do this we need to call a method called saveErrors()
Ex:- {

Public class loginAction extends Action

Public AF execute(--------) throws Exception

ActionErrors aes=new ActionErrors();

If(-----)

--

--

If(! Aes.isEmpty())

saveErrors(req,res);

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--

--

}}

If we save ActionErrors object in to request object then any it is display

the error message on browser it is using <html:errors)> on the browser

DAF does not support validation at Action level.

Enter.jsp
Username:- as salAction

Salary:- DAF

U entered salary 8,200 it is invalid

Enter.jsp

Uname:-

Sal:-

In java two types datatypes.

1) Value type converting value type into reference type is called

boxing
2) Reference type revers is called unboxing.

Int k=49; value type

Integer i= new integer(k) reference type

Int k= i.intvalue(); } unboxing

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-->save Errors(req,res) this method is given base class. Ie. Action that
way no need to necessary objects directly we can call

Servletcontext ctx= getserveltcontext() directly call.

Ex 3:- the following example is for using DAForm and validating the input
at action class.

If input salary is valid then it return success and bonus value will be
printed if not valid then againe input page will be given back and dynamic
error message is printed on the browser.

EX2:- EXAMPLE2

SRC

salAction.java

WEB-INF

Web.xml

Struts-config.xml

Classes

*.classes

Sathya .properties

Lib

x.jar

enter.jsp

success.jsp
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< %-- enter.jsp--%>

< % @ taglib uri=

< % @ taglib uri=

< html: errors/>

<html : form action= test.do>

<bean:message key=enter.name/>:<html:text property=ename/><br>

<bean:message key=enter.sal/> :<html: text property=esal/><br>

<html.submit value=click/>

</html:form>

STRUTS.CONFIG.XML:-

<strut-config>

<form-beans>

<form-bean name=f1 type=org.apache.struts.action.DAF>

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<form-property name=ename type=java.lang.string/>

<form-property name=esal type=java.lang.double/>

</form-bean>

</form-beans>

<action pathj=test name=f1 type=salAction>

<forward name=success path =/success.jsp/>

<forward.name=failure path=/enter.jsp/>

<action>

</action mapping>

<message-resource parameter =sathya/>

</s-c>

salAction.java

import org.apache.struts.action.*;

import javax.servlet.httpx;

public class salAction Extend Action

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Public AF execute(--------)

DAF df=(DAF) form;

String on=(string)df.get(ename);

Double d=(Double)df.get(esal);

Double s=d.double value();

ActionErrors aes=new ActionErrors();

If(S>8000)

ActionMessage =new ActionMessage() sal.invalid,d);

Aes.add(esal,e);

If(!aes.is Empty())

saveErrors (req,res);

if(s<=8000)

Integer i1=new integer(500);

Req.setAttribute(bonus,i1);

Retrun mapping.find forward(success);

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Else

Ref

}}

In the above Action class while constructing AM object, along with the
key, we are passing double object also as a parameter, because the error
message is a dynamic message. And if we want replace a value in place of
a parameter of message then we need to pass an object but not a
variable.

In the above Action class we called saveError() directly. It means this

method is given action base class. And we can call base class method
directly in the derived class.

If the given salary is <: 8000 then we are assigning some bonus and this
bonus is printed in the browser by the success page. In order to transfer
the bounus value from Action. Class to jsp , we are using attributes api of
request object.
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If we want to transfer a value from action class to a jsp then we need to

write setAttribute() in the Action class and getAttribute() in the

JSP:- durga.properties.file

# sathya.properties

Enter.name= username

Enter.sale=salary

Sal.invalid= <h2> o entered salary {0} , it is not valid </h2>

In the above we use parameter {0}. It is to replace dynamic value at run

time. While constructing a message. We can use a maximum of
parameters(from {0} to {3})

Success.jsp:- < % -- success.jsp--%>

< % object o=request.getAttribute(bonus);

Integer i=(integer)o;

Int r= i.intValue();

Out.println(bonus=+r %>
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Upload.jsp

Select a file

Submit

<input type = file>->ordinary html

<html:file./> struts is give

Public class upload extends AF

Private formFile ff;

When submit button then file path is stored in ff.

Public class uploadAction extends Action

P AF execute(----)

Upload uf= (upload) form;

Formfile f=uf.getFf();

Byte b[] f.getfileData();

<html:form action= upload.do

Enctype=multiplication/form-data>

Select a file=<html:file property:ff/>

<html.submit/>
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</html:form>

FILE UPLOADING IN STRUTS:- while working with servlet (or) jsp

individually, if we want apply (or) implement fileuploading mechanism
then we have depend on third party APIs provided.

So that uploading is possible.

forExample,we generally use java zoom API per uploading a file from client
side to serverside in awebapplication.

If we use third party ApIs then our application depends on third party
libraries.so we have to add those libraries in to our application lib folder
and as well as into the class path.

In struts fws we have build in mechanism for uploading a file on to a

server.

In struts fws a free defined class is provided for storing the uploaded file
path and its data called FarmFile.

FarmFile is given in org.apache.struts.upload.* package this is the smallest

package is struts, this package is containe only one class that is FormFile.

The following changes arre required in a struts application in order to

develop file uploading.
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1)in input jsp page, we should add enctype attribute for html.form with a
value multipart formdata.

multipart/formdata means the uploaded file can containe any type of

data.

<html:form ation=upload.do enctype=multipart/fordata>

In order to get a file text box that is a textbox with a browse button, we
need to use on html tag called <html.file property=ff/>In actionform
class,we need a property of type FormFile and then generate the setter
and getter per it.

Example:- public class uploadform extends actionfrom

Private FormFile ff;

setter

getter.

}
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4)in action class of struts, we need get the formFile object and then by
using this methods of this class we need to read the uploadfile data.

Finally we need FileoutputStream per written the uploaded file date into a
serverside file.

Forex:- public class uploadAction extends Action

Public AF execute(---) throws Exception.

Uploadform uf=(uploadForm)form;

FormFile f=uf.getFf()

Byte b[]=f.getFileDate();

String frame=f.getFileName();

FOS fos =new FOS (fname)

Fos.write (b)

..

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DEVELOPING A STRUTS APPLICATION IN MY ECLIPSE:-

Step1:- open my eclipse ide and enter some work space name

Step2:- click file menu new project expandmyEclipseexpand

java enterprise projects->select web project next enter project
name(upload project) finish

Step3:- RT click on projectnameMyEclipseadd struts capabilities

remove package for names and default application resources finish.

Step4:- RT click on proect name newother expand my eclipse

expand webstrutsexpand struts1.2-> select struts1.2 Form
nextname(frm1) superclass(Actionform) form type(uploadForm)
finish

UPLOADFORM.JAVA:-

Import

Public class uploadform extends actionForm

Private FormFile ff;

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Return ff;

P void setFf(FormFile ff);

This.ff=ff;

Step3:- RT click on project name new other myeclipse expand

web-struts struts1.2 expand select struts1.2 Action next
path(upload) Type(uploadAction) name(frm1) uncheck
valibleForm select forwardstab add buttonname.(success)
path(/success.jsp) add similarly failure.--> finish.

UPLOAD ACTION:-

Public class uploadAction extends Action.

Public AF execute(.)

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uploadForm uf=(uploadForm)form;

FormFile f=uf.getFf();

Byte b[]=f.getFileData();

String fname=f.get filename()

fileoutputStream fas=new file outputstream fname);

fos.write(b);

return mapping.findforward(success);

Step4:- RT click on project name new JSP JSPname(uploading)ok

<!upload.jsp

%@taglib uri=http:// struts.apache.org/tags-htmlprefix=html %

<center>

<html:form action=upload.do enctype=multipart/form-data>

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Select a file: <html:file property=ff/><br>

<html:submit valueUPLOAD/>

<html:form>

</center>

Success.jsp:-

<% out.println(<h2>upload done</h2>);%>

Failure.jsp:-

<%out.println(<h2>upload is failed</h2>);%>

ADDING A SERVER IN IDE:-

Click on window menu preferences select my eclipseat leftside and

expand expand application servers expand tomcat5.x at Rightside
select enable a click on browse button and select tomcat home
directory click on apply click ok.

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DEPLOYEMENT:- RTclick on projectname my eclipse select add and

remove project deployements select project addbutton- select
server (tomcat5.x) finish (successfully develoyee) ok

START THE SERVER:- click on serversicon tomcat5.x start

BROSWER(SEND A REQUEST):- click on window menu show view web

browser and type the following request.

http:// localhost:2013/uploadExample/upload.jsp.</

reset() of formBean class:-

whenever deployee the app then the tiie container will be created of
object of action servlet.

Whenever.object is created first constructed will be called

In input containe checkbox then use reset() is used default scope of

FormBean is session. Use reset() if the FormBean is request no need to use
reset()

Java compiler is write constructor not JVM.

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RESET() OF FORMBEAN:-

In a formsBean class, the input values gien by a client will be stored. To

store the client input setter methods of the calling setter methods, reset()
will be called.

just before calling setter methods, reset() will be called.

Reset() is to initialize form bean variable with default values, before

storing the new values into formBean variables.

If input page contains textbox(or) dropdown box (or) radio buttons..etc

then all parameter will be send along with request form client side.

If we dont write reset() then setter methos will be called directly and
previous values are overridden with the new values.

The problem aries, when input page contains checkbox parameter. The
problem in if we dont select a check box then that parameter does not
come to server. So its related setter method will be not called. And hence
the previous values will not be overridden with the new value. So the
previously selected value remains same.

If the previous value is not overridden with new value then we will get
unexpected output. So inorder to overcome this problem, we need reset()
in the FormBean class.

Reset() is required when FormBean object in sessionscope and if the page

containes checkbox.

EXCEPTION HANDLING IN STRUTS:-

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Exception are rised in Action class but not ActionForm becaz we are
implementing b.login Action class.
When we write throws Exception are can be handle that exception
If really exception is raised in execute() of action class.

Public class restAction extends Action

P AF execute(----)

Try

}catch (Exception) {}

}}

To handle the best approach is declaration but not programmatic

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NOTE:- while developing struts applications, at FormBean level, there is

no chance of getting on exception. But there is a change of getting the
errors while validating the user input.

In an Action class of struts application , there is a chance of getting an

exception .becoz the Action class containes business logic.

if we do not apply exception handling in struts the exception stacktance

information is printed on client browser,whenever an exception is
occure but the clients are unkown about the technologies, so a client
can not understand the problem and finally our project become failed.

In order to get out of the above problem,we need apply exception

handling for an Action class apply exception handling for an Action class
I struts application.

To handle an exception, we have the following two approaches.1)

programmatically.by including try and catch blocks.

3) Declaratively by including <exception> tag in struts configuration file.

Action path=/login name=frm,type=Testapplication>

<exception.key=key resource bundle

Type=java.lang.Exception
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Local exception path=/error.jsp/>

<f..>

<f..>

</action>

<global-exception>

<exception key=key

Type=..

Path=/error.jsp/>

</global-exception>

<action mapping>

If we have handle exception in programmatically then for each

modification done on exception,we have to recompile,redeployee restart
the server so this approach becomes complex.

In order to overcome the above problem we can use declaration

exception handling.
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In declarative exception handling, we can configure an exception either

locally (or) globally.

If we configure an exception locally with in an action class then that

exception handling will be done only for that one actionclass.

If we configure an exception globally it wil handle the exception related all

action classes.

If an exception is occurred while executing an action then, the controller

first verifies for local exception handling and it is not available check for
global exception handling.

If an exception occurs then the error message should be taken from the
resource bundle and we need to define an error separately and that error
page displace error message by using<html:error/>

Ex:- <action path=/login name=frm1 type=login Action

<Exception key=key type=java.long.exception path =/error.jsp/>

<f------/>

<f------/>

</action>

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If we want declare an exception as a globalexception then we need to

configure under <global-exception>this tag must be written <action-
mapping>

Ex:- <global-exception>

<exception key=key& type:java.long.exceptionpath=/error.jsp>

</global-exception>

GLOBAL-FORWARDS:- when multiple action classes in a struts application

are sharing same out put pages then in stated of configuring then as local
,we can of configure as global.

If we want configure as global we need <global.forward>

For an action if both local and global forward are written then the
preference will be given for the <local-forwards>

Ex:- <global-forward>

<forward name=success path=/success.jsp/>

<forward name=failure path=/failure.jsp/>

</global-forward>

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ValidatorFramework in Struts:

generally,before executing business logic for a given client request,we

apply validations on the user input.if validations success then the business
logic will be executed.

In order to apply input validations,we can use any one of the following
two approachs.

1)programatic approach.

2)Declarative approach.

In progamatic approach, a programmer has to override validate() in the

formbean class.

In

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