MIDlet framework's design pattern

What design pattern does the MIDlet framework work on?

That's just as silly as asking:
"What design pattern doesn J2me work on?"
A framework doesn't work on a particular design pattern. The software you write does, and surly the api of the framework will make use of several pattern.
Why not take a look at the api yourself and find out?

Similar Messages

J2ME framework and design patterns

Hi everyone.
I'm thinking of building a few J2ME applications, and was wondering if there are any frameworks for this (i.e. for building midlets)? For web applications you have frameworks like Struts (Jakarta/apache), but I've not found anything for J2ME.
Also, any known and proven J2ME design patterns would be of great help!
Thanks for all your help!
Best regards,
Arnt

Hi
AFAIK there r no frameworks, you dont need them - everything you code should be as simple and straightforward as possible.
Hmmm... proven design patterns, well, as I've found standard Java DP can't be used in J2ME, cause you need to do everything with small amount of memory and processing power. Object programming is cool, but it makes big impact on speed of code and on size of generated classes.
And believie me, sometimes those 2-3 kb make difference (eg. on Nokia 6310i, where you have 30 KB of memory, on 3510i it's about 60KB...)
So, one patter of which I can think about is - make your code simple :)
regards
Leszek

A beginner to design pattern(Struct,Spring & Hibernate framework)

Actually I am beginner to MVC2 Approach of complex application incorporated by design pattern as Struct,Spring & Hibernate framework.
Currently I am learning JSP Concepts,I have one doubt.
(1)What are the things I should grasp even before taking off to Design pattern?
Help me anyone plz?
With Regards,
Stalin.G

[email protected] wrote:
Actually I am beginner to MVC2 Approach of complex application incorporated by design pattern as Struct,Spring & Hibernate framework.
Currently I am learning JSP Concepts,I have one doubt.Just one?
>
(1)What are the things I should grasp even before taking off to Design pattern?You should understand core Java very, very well.
You should know JSPs using JSTL without scriptlets.
You should understand relational databases and SQL.
You should understand HTML and HTTP.
Personally I think Struts, Spring, and Hibernate all at once are well beyond any beginner.
It's hard to advise you on what to do without knowing your capabilities and the problem you're trying to solve, but I think you should try it first using just JSPs, servlets, and JDBC. Get that to work and then refactor it to use the frameworks. You'll understand and appreciate them more that way.
%

Producer/Consumer Design Pattern + DAQmx + Event Structure

Dear community users,
at the moment I try to implement the Producer/Consumer Design Pattern into my current project. For this purpose I am trying to make a "minimal-example" in which I use the Producer/Consumer Design Pattern for the data acquisition and analysis (display in GraphXY, calculation etc..) process. In the Producer Loop I perform the data readings via DAQmxRead.VI and in the Consumer Loop, in this example only, I display the data in a GraphXY. At the same time I want to control the data acquisition via an Event Structure, for example Start Measurement/Stop Measurement Buttons. To configure the measurement time, for example if the user only wants to measure 150 sec, I use the Time Out Event of the Event Structure. This is a technique which is often used, when data acquisition and Event Structures are used at the same time (Excuse me if this is wrong!). Due to understand the Producer/Consumer Design Pattern I looked up in the Template\Framework of LabVIEW.
In the attachment you will find my "minimal-example", which -sadly-, not working. What should I do ?
Thank you.
Best regards,
tugrul öztürk
Attachments:
daqEngine_PCP.vi ‏35 KB

Your VI will never stop due to the Ok Button that stops the producer loop is read OUTSIDE of the loop. Add an event case for it.
Move the Start and the Ok Button inside of their respective event cases. This will allow the latch to reset when they are read.
Change the Ok Button to a stop button.
Use a Greater Or Equal instead of Equal for the measurement time comparison. What if somebody randomly changes it to 0 on you? Again, you will never stop.
Is the DAQ only supposed to read for "Measurement Time". Right now, it constantly reads. So if you don't use the DAQmx Read, you will get a buffer overflow error. You need to put the DAQmx Start Task inside of the Start event case and then the Stop DAQmx Task inside of the Timeout event case when the measurement time is exceeded. You should also perform the read regardless inside of the Timeout event case.
I HATE telling the consumer loop to stop by destroying the queue. You can look data that way. Instead, send something an empty array. In the consumer, check for an empty array. If it is empty, stop. Destroy the queue only AFTER BOTH LOOPS HAVE COMPLETED.
You should also report your errors in some way. Simple Error Handler at the minimum.
Since you are using Continous Samples, don't limit the buffer. Leave the Samples per Channel unwired on the DAQmx Timing VI.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

Design Patterns Support in Jdev 10.1.3?

Is Design Patterns Support included as part of JDev 10.1.3. I have seen this support in SAP NetWeaver Developer Studio where you have the option of converting existing classes to implement a certain J2EE/J2SE Design Pattern or create a new class(es) to implement a Design Pattern. I believe TogetherSoft has this support.
Any chances this request is consider in the next major release of JDev 10.1.3?

Dear Shmeltzer,
My company just begins the migration from Oracle Form-based application to pure Java EE one. We will be using JDeveloper v10.1.3, persuaded by it fast GUI building, data-binding features. Before that, we have been trying out Eclipse & JBoss.
We are going to use Swing & JSF for client, and JavaEE 5 for midtier. Persistence layer, will be JPA (EJB3 entity bean persistence) and Spring Framework DAO support. Spring DAO is interesting bcos it gives a consistent style of API (we want to support both JDBC & JPA) and consistent Exception hierarchy too. So our midtier will be partitioned (roughly according to Fowler's patterns) into 3 layers: Service, Domain/Biz Object, Data Access. Thus far is pretty standard.
We are still pretty new to this ADF, and are still exploring.
Now, my initial impression with ADF is that it seems to interfere too much with the kind of pattern we had in mind. The fact that ADF hides too much details from us programmers scares me -- it becomes restrictive and we are helpless as to what are going on inside (with those xml, dcx, etc). For e.g. talk about Service Locator pattern, and we cannot seem to figure out how/where it is implemented. Using ADF Data Control and Biz Components will make all the design patterns "disappear" -- we dont see DAO classes anymore bcos it has been automated. It looks more like 2-tier client-server pattern to me. :-)
We are interested to use ADF data-binding features, so
1) Is it still advisable to use Spring DAO layer?
2) Is it possible to just use ADF in the Client / web tier, while the EJB container remains free of ADF technologies?
Regards.

What is command design pattern? what is the problem that it solves?

Hi i have been reading few articles on command design pattern but was unable to understand what it is and what problem does it solve. As far as my understanding goes if there is a pre specified method in an object that could execute and perform the necessary activities then it is called as command design pattern. Why is it named as command design pattern, it is because in a shell we use commands to retrieve output. For example when we type "dir" in dos command prompt it returns the list of files. so here we have to remember a preexisting exe file named "dir" which does something when used. So here like we call it command because when "dir" is passed to the computers it returns something that is expected. may be the computer obeys the command issued and return something back. So like wise if there is a method that is defined as as the command, for example in struts framework the action class must have a method "execute()" which is called by the framework to execute the necessary action mapped to it. So if there is a predefined method like "execute" in struts then the object is said to be followed command design pattern. So what actually does it solve?
What ever i have written is my understanding from the articles i have read about the design pattern. So kindly correct me if i am wrong. Help me understanding what actual problem does this pattern solves. Thanking you in advance.

This is really off-topic for these forums. You might do better on StackOverflow.com. I'll just say that although the first Design Patterns book came as a revelation to me, it was more for (a) the nomenclature (decorator, factory, facade, etc) which is still with us and (b) about five of the original patterns, which told me things I didn't already know. I've never used any of the others, including Command, and the whole design patterns thing quickly degenerated into farce with what seemed like a sustained attempt to reduce the whole of computer science to design patterns, which really isn't the point. As an example, there is one in another book called Type Object, which is nothing but 3rd normal form, which can be defined roughly in a couple of sentences. This pattern went on for dozens of pages with a very artificial example. I wrote to the mailing list about it: 'Type Object considered hilarious'. I got a rude reply from the original author, which I guess I expected, but also an incredible response from the list owner, saying I should recast my objections in the form of a design pattern. That lost it for me. True story. Moral: don't take this religion, or any IT religion, too seriously. They come around every 18 months or so with the regularity of the next bit of Moore's Law. I've seen dozens of them come and go since 1971, all with something to say, all 90% nonsense.
See here for a longer version of this incident.

Is MVC2 a design pattern or architecture? for yes and no why?

I am using JSF which follows MVC2. Is MVC2 a design pattern or architecture? For yes and no why? what is the difference between design pattern or architecture?

Hi There,
Maybe this will help answer your questions...
Firstly, MVC2 is a proprietary name for the Microsoft .NET framework based around the Model-View-Controller pattern - it is an updated version of their first attempt - MVC.
The Model-View-Controller pattern harks back to the days of SmallTalk, and as far as I am aware is not included in the original Gang Of Four design patterns, although there is no reason why it can't be considered a design pattern.
Software architecture is about how different parts of the system fit (interface) together and how they relate, including static relationships (cardinality relationships, state) and processes (what happens when), it most often consists of many design patterns each used to address the various needs of a complete system.
Hope this helps
Rich

Design Patterns: Do you have a good STRATEGY?

1. Context: Create a XML file. And since there
are many ways: DOM, WAY1, OTHERWAYS, ETC...
2. Question: As a Design Patterns application purpose,
can we use the Strategy Pattern? Is it appropriate one?
If not, what are the alternatives?
CLIENT
--CREATEXML (CONTEXT)
----CREATEXMLSTRATEGY (STRATEGY)
------CREATEXMLSTRATEGY_DOM (CONCRETE STRATEGY)
------CREATEXMLSTRATEGY_WAY1 (CONCRETE STRATEGY)
------CREATEXMLSTRATEGY_OTHERWAYS (CONCRETE STRATEGY)

Hi Paul,
I have myself recently started doing the Design Patterns and believe me after understanding the Patterns OOD have become more clear. >>1. Context: Create a XML file. And since there are many ways: DOM, >>WAY1, OTHERWAYS, ETC...
My understanding regarding the Strategy and Tempelate method Pattern has become stronger after reading the "Thinking in Patterns in Java" , the author is mentioning there these Behavioural Patterns are used for Framework development , infact there he has used example of Framework development.
Now regarding your question it seems to me that your entire applicaiotn can use the Creational Pattern , like Abstract Factory.You can use the DOM,WAY1,OTHERWAYS as the concrete Prodcuts and all will be extracted from the Factory XMLGeneratorFactory.
Strategy Pattern is changing the algorthims at the run time , the temlate can work for your applicaiton but then what you are trying to achieve.Currently this much I can say ..
Let us see for more opinions
Regards
Vicky

Can you suggest a Design pattern for moving a desktop app to web?

Hi,
I have been asked to move a desktop applciaiton which has Serialized files as persistant layer in to Web, can anyone suggest me a good design pattern to accomplish this.

I dont know what data is in the files, but I suggest looking at creating a set of database tables, normalize them, and copying the data to the tables (via java). Have a DBA review your database schema design if possible before copying the data. Then, use MVC design as I describe here:
http://forums.sun.com/thread.jspa?messageID=10786901
Once you get experience in the MVC design described above, your next project can use MVC with a framework such as Java Spring (a more advanced topic). You should read a book cover on Spring to cover on it first.

Design Pattern for low cohesion & coupling

Hi there!
I�m about to make a applictation in swing and don�t have so much experince in this API. Normally I program for the web using J2EE tech like Servlets, JSP, custom tag libs and EJB�s. Therefore my biggest challenge for the moment is to find (/ find out) a good framework for coding in swing and minimize coupling between the participants.
I have good knowledge about the MVC paradigm (in web programming) but finds it difficult to apply my knowledge in the Swing area. Do you have links or can recomend some litterature that handles my little but very frustrating problem?
In advance thank�s
Best regards
Niclas Rothman

Check out Java Design Patterns A Tutorial by James W. Cooper.
I am sure there are many other publications out there, but I am not quite sure what your frustration is related to swing.
Design patters are applicable in many aspects and are mostly language independent. In fact swing uses some of the design patters such at the command pattern in using Actions.
Hope this helps
Neelesh

Design pattern for swind application development

Hello all,
I am trying to develop a new swings application with the centralized database connectivity for the data transaction .Any one please tell me which design pattern is mostly suitable for the GUI application development using swings .
Thanks in advance
sowjanya

Pu - this is your decision.
In order to know which design patterns are suitable for you, you should know what the design pattern do.
So I suggest to read about design patterns:
http://en.wikipedia.org/wiki/Design_pattern_(computer_science)
Note also that ther exists a framework called Spring.
Greetings
Thorsten

Design Pattern for Building Trees (Java)

I'm wondering if there is a design pattern suited to build trees from a given domain object.
public interface DomainObject {
public long getId();
public abstract class Displayable {
private DomainObject domainObject;
private Displayable parent;
private Vector children;
public Displayable(DomainObject domainObject, Displayable parent) {
this.domainObject = domainObject;
this.parent = parent;
this.children = new Vector();
public Displayable(DomainObject domainObject) {
this(domainObject, null);
public Displayable getParent() {
return parent;
public DomainObject getDomainObject() {
return domainObject;
public Displayable[] getChildren() {
return (Displayable[])children.toArray(new Displayable[children.size()]);
public void addChild(Displayable d) {
children.add(d);
Example:
DomainObject O
Displayable D (contains O)
D's parent is C
C's parent is B
B's parent is A
A does not have a parent
A --> B --> C --> D(O)
Method signature
public Displayable buildDisplayable(DomainObject domainObject);
So basically pass in a DomainObject (O) and spit out the Displayable (D), with the tree built up to the root (A).

No I graduated last year from college. I'm trying to improve our SWT/JFace GUI framework. That method signature is just something I thought about. I'm thinking using Factory Pattern will have to do considering I know ahead of time which subclasses of Displayable have parents and children.

Design Pattern for ATE

Looking for suggestions on the best design pattern (using OOP) for an automated test environment application. The current code (LabVIEW only, no Test Stand) has it's own UI and support VIs for selecting the test environment, sequence of tests to run, running a sequence, evaluating test results and outputting pass/fail reports (HTML) and test measurement result files (TDM). The intent was to give the developer a framework where he/she can concentrate on writing the actual tests. Unfortunately, in the environments where it is used, developers always find the framework lacking for their needs and so tend to have their own version by the time they are done. This thing does not scale well nor is it very flexible.
This framework was originally written with LV 6.1. I put it in a LV2011 Project, but it won't build due to its sheer bulk so it's being run strictly under the development environment (which I hate doing). The whole framework needs a face lift.
Any suggestions? I've looked at the AF but it seems "over-qualified" for this, plus I don't have a bunch of parallel processes in this case. Things run pretty much sequentially from the get go just by the nature of the testing.
“A child of five could understand this. Send someone to fetch a child of five.”
― Groucho Marx

You could create pure virtual class that defines your test step API. Methods for the class would consist of things like setup, teardown, execute to name a few. Your developers could use this base class as the template and API for their tests. The methods regulate the format of the data exchange between your engine and their test. I would also recommend that you use packed libraries so that your test steps are basically plugins. Your test sequence would need to contain the name of the appropriate plugin to use in order to invoke the correct test step. This model is flexible and easy to extend.
We are actually investigating using this same approach for our test system. Our current system uses TestStand and we are going to investigate TestStand 2012 ability to use dynamic dispatch to invoke our test steps. It should be interesting. We use other features of TestStand so it would be nice if we can make this work. In your case a LabVIEW only implementation should be fairly straightforward.
Mark Yedinak
"Does anyone know where the love of God goes when the waves turn the minutes to hours?"
Wreck of the Edmund Fitzgerald - Gordon Lightfoot

Flex design pattern for BlazeDS transfer objects

Dear Community,
I have a question regarding the nature of objects transferd from BlazeDS backend to the Flex client.
According to some adobe docs all the presentation logic should be in flex and BlazeDS should provide only services.
The question is what kind of transfer objects should be used? with what level of abstraction?
To make it more clear let's talk about a simple forum application like adobe forums.
I have created a Forum service, which returns a Forum transfer object, which has a List of Threads, with each thread having a List of Messages.
Flex gets the Forum transfer object and does all the presentaiton work.
This is a very nice seperatin of concerns architecture BUT there are two major performance issues:
- when the forum becomes bigger the transfer object will be huge
- the flex will use huge client resources to create the presentation of the forum transfer object.
So my question is what is your strategy/ design pattern for such a problem.
An obvious answer would be create services that include the presentation logic and use transfor objects like ThreadListPage which will include only the first 10 threads.
Thanks in advance

I think you are going to get a few varied types of answers to a general question like this, but I will comment on a few things. First, you should only be transmitting the data that you need to use or display to the user at the time. If this forum was implemented in Flex (I wish) you wouldn't transfer the text for all the threads. You might not transfer the thread text at all (just the subjects), you'd make calls back to the server to fetch that data when and if you need it.
Also, I think you are overestimating the resources required for the Flex "presentation layer". If you think about it, these workstations we have here are pretty idle most of the time when you're at a website. Nowadays there's plenty of processing power just sitting there waiting, so as long as your design isn't flawed the CPU or memory are rarely going to be a bottleneck with Flex.
The way I design, BlazeDS (or GraniteDS etc) should mostly just be "serving data". There is some flexibility available, for example I don't see a problem with putting certain types of business rules (such as a limit on the number of results that can be recieved in a search) within server side code, and validation rules on the Flex side. So there's not too many "industry standards" in Flex yet beyond maybe what's done in the various standard architectures, at least not that I'm aware of.
You might find it beneficial to look into some of the various frameworks/architectures available like Cairngorm, Mate, Swiz, and so on. Learning how they work (looking at examples) would probably answer some of your questions too.

Designing a smart Swing GUI with design patterns

Hi !
I have to build a quite big Swing GUI from
scratch. I would like to use smart design patterns to :
* ensure reusability of some components
* offer a framework-like set of solid classes
to deal with generic problems
* try to respect MVC pattern as close as possible
from the real MVC spirit (not the half MVC
pattern Swing is build upon)
Could somebody give me any link towards ressources/docs/articles dealing with how
to build such a smart Swing GUI ?
Thanx a lot !

Hi !
I have to build a quite big Swing GUI from
scratch. I would like to use smart design patterns to :
* ensure reusability of some components
* offer a framework-like set of solid classes
to deal with generic problems
* try to respect MVC pattern as close as possible
from the real MVC spirit (not the half MVC
pattern Swing is build upon)
Could somebody give me any link towards ressources/docs/articles dealing with how
to build such a smart Swing GUI ?
Thanx a lot !

MIDlet framework's design pattern

Similar Messages

Maybe you are looking for