Association vs Dependency (Offbeat)

Google

Mailing List

Home

Forum Home

JBoss - Java Application Server

Struts - A MVC web framework

Tomcat - JSP/Servlet container

iText - An open source PDF Java Library

JDOM - JDOM XML Parser

J2EE - A mailing list for Java(tm) 2 Platform, Enterprise Edition

J2EE Pattern - An interest list for Sun Java Center J2EE Pattern Catalog

Servlet - A mailing list for discussion about Sun Microsystem's Java Servlet API Technology

JSP - A mailing list about Java Server Pages specification and reference

Struts & Hibernate

Subjects

•	JSP editor plugin for eclipse ?
•	org apache jasper JasperException: Unable to compile class for JSP
•	Tomcat: Connection reset by peer: socket write error
•	Cannot retrieve definition for form bean null
•	Struts Tiles Tutorial (free Struts training)
•	Where do I download Tomcat 4 0 6?
•	Data Access Object (DAO) pattern, example DAO 's
•	Where to download Tomcat v 4 1 24 from?
•	Tomcat 5 0 16 Requested resource not available
•	Oracle Connection Pooling in 3 2 2
•	Servlet : Session invalidate
•	Servlet action is currently unavailable
•	Tomcat/Struts Unicode Encoding/Decoding problems
•	Tomcat and webapplication specific java library path
•	Running a Simple JMS Example
•	Mapping in workers2 properties
•	org apache jasper JasperException
•	Cannot find message resources under key org apache struts action MESSAGE
•	problem with html:text bean throwing exception
•	Cannot find message resources under key org apache struts action MESSAGE
•	invalid direct reference problem with solution
•	Tool for jsp debug Try Sysdeo Eclipse Plugin
•	Tomcat 5 Cannot load JDBC driver class 'null ' SQL state: null
•	weblogic ejbc
•	java properties file
•	Jboss 3 2 3 Coyote Can 't re
•	Tomcat 5, Apache2 and mod jk2 integration problem
•	JBoss example problem new to J2EE
•	url string for connecting jboss to oracle
•	Value attribute of <html:checkbox
•	javax servlet ServletException: BeanUtils populate
•	HTTP Status 404 The requested resource is not available
•	5 0 18: Windows XP Pro vs Windows 2000

Association vs Dependency (Offbeat)

Association vs Dependency (Offbeat)

2003-12-30 - By ShriKant Vashishtha

Back

Reply: 1 2 3 4 5 6 7 8 9 10 >>

Hi Ashraf,

I am sorry if I understood you correctly.
What do you mean by abstraction in this context and its relation with
dependency. When you talk about template, are you talking about template
method design pattern or C++ templates?

Please clarify.

Thanks
-ShriKant

ashraf galal <ashrafwg@(protected)>
Sent by: An interest list for Sun Java Center J2EE Pattern Catalog
<J2EEPATTERNS-INTEREST@(protected)>
12/30/2003 01:46 PM
Please respond to An interest list for Sun Java Center J2EE Pattern
Catalog

To: J2EEPATTERNS-INTEREST@(protected)
cc:
Subject: Re: Association vs Dependency (Offbeat)

ShriKant;
Dependency relates the model elements themselves and does not require a
set of instances for its meaning.<?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" />

Dependency indicates a situation in which a change to the supplier may
require a change to or indicate a change in meaning of the client in the
dependency.

1- has a reference to an object directly.
InstanceOf and abstraction are example of this type.
2- has a reference to an object indirectly via some operation
parameters:
A template class is an example of this type.
You can not use a template directly, you have to instantiate it first.
Instantiation involves binding these formal template parameters to actual
ones.
The result is a concrete class hat can be used as any ordinary one.
Dependency between packages is another example.

Also I would like to keep your attention that association and
generalization fit within the general definition of dependency, but they
have their own model representation and notation and are not usually
considered to be dependency (UML).

So we need to make explicit relationship between UML and J2EE.

Ashraf Galal
(416)804-8359
>From: ShriKant Vashishtha >Reply-To: An interest list for Sun Java Center
J2EE Pattern Catalog >To: J2EEPATTERNS-INTEREST@(protected) >Subject: Re:
Association vs Dependency (Offbeat) >Date: Tue, 30 Dec 2003 09:01:54 -0600
> >Hi Ashraf, > >I am quite clear regarding unidirectional and
bidirectional association. >But could you please elaborate the following
points more, may be with some >examples. > >- has a reference to an object
directly. >- Has a reference to an object indirectly via some operation
>parameters. > >Thanks >-ShriKant > > > > >ashraf galal >Sent by: An
interest list for Sun Java Center J2EE Pattern Catalog > >12/29/2003 11:22
PM >Please respond to An interest list for Sun Java Center J2EE Pattern
>Catalog > ; > > To: J2EEPATTERNS-INTEREST@(protected) > cc: > Subject:
Re: Association vs Dependency (Offbeat) > > >Actually, these concepts is
UML not a java. You are quite well >understanding but I would like to
illustrate the difference between them >and give an example. > />
>Dependency : >Anytime a class uses another class in some fashion, a
dependency exists >between the two. >A dependency exists of a class: >-
has a reference to an object directly. >- Has a local variable based on
another class. >- Has a reference to an object indirectly via some
operation >parameters. >- Uses a class's static operation >Also there are
dependency between packages. > >Association: >There is two types of
association, unidirectional and bi-directional >associations.
>Unidirectional association implies that an object of the class may invoke
>methods on the other class. >In java, this manifest itself as an instance
variables on the class that >may invoke methods. > >Example: >Public class
customer > { > ?. > Public Address homeAddress; > > ?? > } > >public class
Address { >?.. >} > >bi-directional association means that either object
in the association may >invoke methods on other. >In java, this results in
an instance variable on each class based on the >type of the other class.
> >Example; >Public class Team > { > LinkedList teamPlayers = new
LikedList(); > teamPlayers.add(new teamPlayer(?)); > ??? } > > public
class teamPlayer { > Team memberOf; > ?. > } > >Ashraf Galal
>(416)804-8359 > >From: ShriKant Vashishtha >Reply-To: An interest list
for Sun Java Center >J2EE Pattern Catalog >To:
J2EEPATTERNS-INTEREST@(protected) >Subject: >Association vs Dependency
(Offbeat) >Date: Sun, 28 Dec 2003 14:17:03 -0800 > > >Hi All, > >I am
slightly confused in finding the difference between >association and
dependency. > >For me, whenever the variable is intialized >at a local
scope or passed as a parameter in a method, its denoted as >dependency.
However, for association, I believe, the object needs to be on >global
scope (as an instance variable). However, I rarely use any object >at a
global scope, unless I know that it is used for maintaining the state >of
class or need to be used across different methods. So most of the time, >I
end up with dependency . > >Am I missing something over here. > >Thanks >
>-ShriKant > > >-- ---- --- -- ---- ---- ---- ---- >Do you Yahoo!? >
>Protect your identity with Yahoo! Mail AddressGuard > >
>===================================================================== >
>Companion Site: http://www.corej2eepatterns.com >J2EE BluePrints: http://java
.sun.com/blueprints/corej2eepatterns >List Archive: http://archives. java.sun
.com/archives/j2eepatterns-interest.html >Unsubscribing: email
"signoff J2EEPATTERNS-INTEREST" to >listserv@(protected) > >MSN 8 helps
ELIMINATE E-MAIL VIRUSES. Get 2 months FREE*.
>====================================================================
>Companion Site: http://www.corej2eepatterns.com J2EE BluePrints: http://java
.sun.com/blueprints/corej2eepatterns List Archive: http://archives.java.sun.com
/archives/j2eepatterns-interest.html Unsubscribing: email "signoff J2EEPATTERNS
-INTEREST" to
>listserv@(protected) > >
>====================================================================
>Companion Site: http://www.corej2eepatterns.com >J2EE BluePrints: http://java
.sun.com/blueprints/corej2eepatterns >List Archive: http://archives.java.sun.com
/archives/j2eepatterns-interest.html >Unsubscribing: email "signoff J2EEPATTERNS
-INTEREST" to
listserv@(protected)

Add photos to your e-mail with MSN 8. Get 2 months FREE*.
====================================================================
Companion Site: http://www.corej2eepatterns.com J2EE BluePrints: http://java
.sun.com/blueprints/corej2eepatterns List Archive: http://archives.java.sun.com
/archives/j2eepatterns-interest.html Unsubscribing: email "signoff J2EEPATTERNS
-INTEREST" to
listserv@(protected)

====================================================================
Companion Site: http://www.corej2eepatterns.com
J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
List Archive: http://archives.java.sun.com/archives/j2eepatterns-interest.html
Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to listserv@(protected)

 Hi Ashraf,
 
 I am sorry if I understood you correctly.
 What do you mean by abstraction in this
context and its relation with dependency. When you talk about template, are you
talking about template method design pattern or C++ templates?
 
 Please clarify.
 
 Thanks
 -ShriKant
 
 
 
<table width=100%>
<tr valign=top>
<td>
<td>ashraf galal <ashrafwg@(protected)>

 Sent by: An interest list for Sun Java
Center J2EE Pattern Catalog <J2EEPATTERNS-INTEREST@(protected)>
12/30/2003 01:46 PM
 Please respond to An interest list for Sun
Java Center J2EE Pattern Catalog
 
<td>        
         To:   &nbsp
;    J2EEPATTERNS-INTEREST@(protected)
         cc:   &nbsp
;    
         Subject:  
     Re: Association vs Dependency (Offbeat)</table>
 
 
 ShriKant; 
 Dependency relates the model elements
themselves and does not require a set of instances for its meaning.<?xml
:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /
>
  
 Dependency indicates a situation in
which a change to the supplier may require a change to or indicate a change in
meaning of the client in the dependency. 
  
  
 1-     has a reference to an
object directly.
 InstanceOf and  abstraction are
example of this type.  
 2-     has a reference to an
object indirectly via some operation parameters:
 A template class is an example of this
type.
 You can not use a template directly,
you have to instantiate it first.
 Instantiation involves binding these
formal template parameters to actual ones. 
 The result is a concrete class hat can
be used as any ordinary one. 
  Dependency between packages is
another example. 
  
  
 Also I would like to keep your
attention that association and generalization fit within the general definition
of dependency, but they have their own model representation and notation and
are not usually considered to be dependency (UML).
  
 So we need to make explicit
relationship between UML and J2EE. 
 

 
 

 Ashraf Galal 
(416)804-8359
 >From: ShriKant Vashishtha >Reply
-To: An interest list for Sun Java Center J2EE Pattern Catalog >To:
J2EEPATTERNS-INTEREST@(protected) >Subject: Re: Association vs Dependency
(Offbeat) >Date: Tue, 30 Dec 2003 09:01:54 -0600 > >Hi Ashraf, > &gt
;I am quite clear regarding unidirectional and bidirectional association. &gt
;But could you please elaborate the following points more, may be with some &gt
;examples. > >- has a reference to an object directly. >- Has a
reference to an object indirectly via some operation >parameters. > &gt
;Thanks >-ShriKant > > > > >ashraf galal >Sent by: An
interest list for Sun Java Center J2EE Pattern Catalog > >12/29/2003 11
:22 PM >Please respond to An interest list for Sun Java Center J2EE Pattern
>Catalog > ; > > To: J2EEPATTERNS-INTEREST@(protected) > cc: &gt
; Subject: Re: Association vs Dependency (Offbeat) > > &gt!
;Actually, these concepts is UML not a java. You are quite well &gt
;understanding but I would like to illustrate the difference between them &gt
;and give an example. > /> >Dependency : >Anytime a class uses
another class in some fashion, a dependency exists >between the two. >A
dependency exists of a class: >- has a reference to an object directly. >
- Has a local variable based on another class. >- Has a reference to an
object indirectly via some operation >parameters. >- Uses a class's
static operation >Also there are dependency between packages. > &gt
;Association: >There is two types of association, unidirectional and bi
-directional >associations. >Unidirectional association implies that an
object of the class may invoke >methods on the other class. >In java,
this manifest itself as an instance variables on the class that >may invoke
methods. > >Example: >Public class customer > { > ?. > Public
Add!
ress homeAddress; > > ?? > } > >public class Address {
>?.. >} > >bi-directional association means that either object in
the association may >invoke methods on other. >In java, this results in
an instance variable on each class based on the >type of the other class.
> >Example; >Public class Team > { > LinkedList teamPlayers = new
LikedList(); > teamPlayers.add(new teamPlayer(?)); > ??? } > >
public class teamPlayer { > Team memberOf; > ?. > } > >Ashraf
Galal >(416)804-8359 > >From: ShriKant Vashishtha >Reply-To: An
interest list for Sun Java Center >J2EE Pattern Catalog >To: J2EEPATTERNS
-INTEREST@(protected) >Subject: >Association vs Dependency (Offbeat) &gt
;Date: Sun, 28 Dec 2003 14:17:03 -0800 > > >Hi All, > >I am
slightly confused in finding the difference between >association and
dependency. > >For me, whenever the variable is intialized >at a local
scope or passed as a parameter in a method, its denoted as &gt!
;dependency. However, for association, I believe, the object needs to be on
>global scope (as an instance variable). However, I rarely use any object &gt
;at a global scope, unless I know that it is used for maintaining the state &gt
;of class or need to be used across different methods. So most of the time, &gt
;I end up with dependency . > >Am I missing something over here. > &gt
;Thanks > >-ShriKant > > >-- ---- --- -- ---- ---- ---- ---- &gt
;Do you Yahoo!? > >Protect your identity with Yahoo! Mail AddressGuard &gt
; > >=====================================================================
> >Companion Site: http://www.corej2eepatterns.com >J2EE BluePrints:
http://java.sun.com/blueprints/corej2eepatterns >List Archive: http:/
/archives. java.sun.com/archives/j2eepatterns-interest.html >Unsubscribing:
email "signoff J2EEPATTERNS-INTEREST" to >listserv@(protected)
> >MSN 8 helps ELIMINATE E-MAIL VIRUSES. Ge!
t 2 months FREE*. >================================================
==================== >Companion Site: http://www.corej2eepatterns.com J2EE
BluePrints: http://java.sun.com/blueprints/corej2eepatterns List Archive: http:
//archives.java.sun.com/archives/j2eepatterns-interest.html Unsubscribing: email
"signoff J2EEPATTERNS-INTEREST" to >listserv@(protected) > &gt
; >==================================================================== &gt
;Companion Site: http://www.corej2eepatterns.com >J2EE BluePrints: http:/
/java.sun.com/blueprints/corej2eepatterns >List Archive: http://archives.java
.sun.com/archives/j2eepatterns-interest.html >Unsubscribing: email &quot
;signoff J2EEPATTERNS-INTEREST" to listserv@(protected) 
 

<hr>Add photos to your e-mail with 
<a href="ht tp://g.msn.com/8HMAENCA/2746??PS=">MSN 8. </a>Get 2 months FREE*. 
 =======================================
============================= Companion Site: http://www.corej2eepatterns.com
J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns List Archive:
http://archives.java.sun.com/archives/j2eepatterns-interest.html Unsubscribing:
email "signoff J2EEPATTERNS-INTEREST" to listserv@(protected) 
 
 
====================================================================
Companion Site: http://www.corej2eepatterns.com
J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
List Archive: http://archives.java.sun.com/archives/j2eepatterns-interest.html
Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to listserv@(protected)