Sunday, December 29, 2013

Why I plan to leave RichFaces

Having recently worked with upgrading RichFaces 3.3 to 4.3.1 I have come to the conlusion.... "It basically s*cks". I will give some reasons why:

  • Huge makeover of tags
  • Removal of tags
  • Changes in attibutes
  • Too many attributes.
Maybe RF was good when it came, because there was not so much else. But the makeover from 3 to 4 made an upgrade a real pain in the a**.

Googling help for RF in most cases gives result for 3.3.x solutions. I have found it hard to find any useful information about 4 or later. This makes an upgrade hard since it is not easy to find the proper information how things are done with 4.3.x, specially how to replace stuff that is removed from 3.3.x since there is not a decent upgrade guide to be found either. Maybe I have missed some place where all this is written, but weeks of Googling without finding anything is another problem, the documentation s*cks when there is not easy to find what you need.

Makeover of Tags

Some examples: 


Removal of tags

rich:modalPanel dissapeared. Well WHY? I think a lot of people used it, now all that code have to be totally rewritten.
rich:layoutPanel was removed. Well now I have found nothing obvious to replace it so back to postitioning by div and css.


Changes in attributes

Take rich:dataTable as an example: some attributes removed, some new, and also changes from camel-case to all lower case attributes but not all. WTF? do you really want someone to use the framework after an upgrade, do not change EVERYTHING. All event-attributes was changed to lowercase ("onRowClick" to "onrowclick"), but not things like "rowClass".

rich:panel: attribute "header"changed meaning from label to space-separated list of styles (???)

Too many attributes

a4j:commandButton: 32 attributes
a4j:commandLing: 37 attributes
rich:dataTable: 34 attributes

This is just a few examples, there is a lot of headache upgrading from 3.3.x to 4.3.x, not only on the surface, if you are using classes in your backing code, be aware, the package structure is also changed, classes have dissapeared and things just stop working. Changing the tags may look hard enough, but when new ones are in place you still probably have strange bugs that need fixing since things that worked before does not work any more.

If I would choose next upgrade, I would not choose RF 5, but go for PrimeFaces instead.

Wednesday, November 13, 2013

Designing a “modular” web application

Background

I would like to separate functionality for a web application into separate jar-modules and include these in a war project.
The purpose for this is to separate development and deployment, that is, to develop functionality separately and include it in the war-packaging and it should automatically be usable with templates, menues etc.
Sorry if the code don't display so well. But putting codes with Generics is not so well handled by Bloggers editor, so until I have time to fix it you will have to live with it ;) and I will use [] instead of <>


Structure

To make it modular it is nescessary to have some common code (placed in “common-web”). The structure for this is basically:

  • common-web: will contain code common to modules and web-applications.
    • templates: for reuse in different modules, basic templates is put in a common module.
    • login: (out of scope, will not implement login in this example) for reuse of login-form etc. i.e. the same files and functionality applies to all web-applications that uses login.
    • resources: common css and images is placed to be reused.
    • menu: functionality to assemble n menu(es) from m modules so they will present in web-applications no matter in what module a page is used.
    • common code: code for hoding and generating menu(es), common utility code for JSF, ManagedBeans etc.
  • war: web-project with war-packaging that will use modules.
  • webmoduleA..X: functional parts that implement a function or group af functions that logically belong together.
    • as an example I will implement at “todo-webmodule” in a PoC to show the functionality.


Menu

Basic functionality for menu is placed in common-web.

What am I trying to solve here?

A module can have different kind of needs, to access parts of its functionality we need a menu with 1 or more items (even if a module can be without menu, for example common-web may not need one, even if it is also a kind of a module).


Requirements:
  • A menu sholud be able to present itself as a top-menu in a menubar
  • A menu should be able to present itself as a part of another menu (i.e. not on toplevel) but in another menu.
  • Should be able to order children of a node.
  • Support to up to 4 levels of menues (more level will not be displayed)


Assumptions:
  • If a menu has no children it should have an action attached (=no expression needed)
  • If a menu has children, it has no action attatched to it.(=no expression needed)
  • Only SubMenus can be placed, not single menues (MenuItem). And they can only be placed in other SubMenus.



Placement:
“/” is root, putting menues under “/” would put them in top menubar.
Take as an example; you have 3 top menus (Admin, Project, Help). These should all be placed under “/”


Further, say we want to capture this endresult for menues.
  • /
    • admin
      • add user
      • list users
    • project
      • add project
      • list projects
      • issues
        • add issue
        • list issues
    • help
      • about


/admin
/admin/add user
/admin/list users
/project
/project/add project
/project/list projects
/project/issues
/help
/help/about

We have Issues under its own grouping and this should be inserted under project. (The reason behind this is that it may be developed in another module and we want to insert it under project in this application)

Ordering

When it comes to ordering, I want to speify an order on all levels. The purpose of this is that when adding top menues dynamically I do not know which order they will appear, hence it is usefull to be able to define it on top-level.
Another purpose is, that since it is possible to insert a menu into another, this may disturb the order or we want the inserted menu group to in another position than it gets inserted to.

This solution for this is to sort all items alphabetically and then resort according to supplied ordering (which is allowed to just use the ones it wants to sort in from start)

Solution

Model



Description


I will describe the solution by taking my example project on bitbucket as an example.
The example project (on bitbucket) have the following structure:


In this example the only “working” code for a MenuGroup that I will implement is the TODO-functionality, and of course the supporting code to have it modular. As goes for the concept of menus I will add a couple of MenuGroups undermodule-web itself. (Do not be surprised if the code here differs from the one on bitbucket, because there may be improvements done in the real code.). There is also mockup code to add the menues as described above to get more than one menu.


To have a menu for “Todo”, the following code will give me that as a “MenuGroup”





To have it modular and generate modules, this is done by having the menu.xhtml and supporting classes in common-web. The most important are MenuBean (that assemble the menu for the view), MenuAssembler (that assembles a menu for MenuBean from the groups it is provided)


To get menu groups aswell as config of orderings and placement from other modules, a bit of CDI is used.




Since we do not know which MenuGroups will exist when developing common code, we inject any type in an Instance. The view will call getMenus() tha if empty will try to assemble the menu. The placement and ordering should be provided from outside aswell, not hardcoded as in this case.


The order we do this is:

  1. add MenuGroups
  2. add rules
    1. placement and/or ordering (defined in a WebMenuConfig implementation)
  3. call assemble()


The last call will assemble the menu and return a list of the top menus. These menus will after returning be rendered in the view.


The implementation of the WebMenuConfig in this case is defined like this:




This will give a menu that looks like:









Thursday, July 12, 2012

"plz give codez..."

or "How to try to get the work done by posting questions"

Hold your hat because this may have some ironic content.

Well this post is going to be mostly about discussions in groups on LinkedIn. And specifically about questions asked in the groups. It seams to be a tendency for freshers from certain countries to try to get the work done by asking help from others. Seriously, LinkedIn is a professional networks site, but that does not mean that the professionals there are suppose to do your work for you.

It is almost amazing to see that some does not have the capability to think just 2 seconds before posting a question or the capability to search either the group in hand or to use a search engine (like Google!) to try to find an answer.

Well lets narrow down to Java because that is my field at the moment. Lets be honest. Getting to know the basics for Java, it is not hard to find resources online. For crying out loud, I think Oracle's (Sun's) documentation  and tutorial online is far better then what can be found for C# (Not that I looked recently). Despite of this, groups on LinkedIn is filled with basic questions, why?

Some examples:
Give me codez (or I do not know anything, but please do the job for me):
"Hi All, I want to learn Collection framework. Will you please tell me the sources where I can get the "Easy to Understand" and "With Examples" and "Real Time Scenarios" ? Need Your Help !!! "
Well, the short answer is, "Google it!!!". To search for this will give more answers than someone is willing to spend time explaining in a group discussion. To answer this I would probably Google for the sources as I do not bookmark these kind of things. I will not give you examples. And certainly to give real time scenarios will make me write a lot, which I am not willing to do for the effort put in in asking the question.
How can we create array of vector or array of arrayList,please reply
Actually a student. But come on, aren't LinkedIn a network site for professionals. Should a question really be a question where the obvious answer is, "See the API documentation" or "We are not doing your homework here!".

Another one:
i am a java fresher...can u suggest how the interfaces given to developers to program...? if possible give some real time examples.....@thanks in advance
How should I give you an example of how this is done? Should I make a movie out of how to check in into SVN created interfaces and show how a newbie check it out and start working?

Here is a different one, but requesting the docs instead of code:
can anyone explain me ,what id maven?also provide me docs.thanks in advance
Or some links and docs:

Please send me best javafx links and pdf. Thanks in advance.
Some Basic Java and API questions:
What is the difference between String Buffer and String Builder?

Abstract classes and interfaces

What is synchronize keyword? Why we use synchronize keyword in java?

what is system , out and println in system.out.println()?and how it works?

What is the difference between HashTable and HashMap?
Ok, here it is:
Java™ Platform, Standard Edition 6 API Specification,
Trail: Learning the Java Language

Language difficulties (or do you think you are in a chat for kids?):

Proper English seam to be some kind of standard. Look at this reply in a thread about an exception in Struts-1
hello "---" wt prob in struts2 ur nw in struts2 ok no problem wt u use eclipse or net bean i hav nt much knowledge in struts1 bu i m working in struts2

plz frnds, tell me.....
Again, in a networking site for professionals, should you really write in a way that teenagers do in a chat?

About interviews:
Hello, In an interview i faced the question "What is your project architecture?"can u plz help me the correct answer
Well, maybe if you do not know what you have done the last couple of years, maybe you should not have that job. One thing that I can tell you is that I have no clue how you worked during those two years.


And people posting jobs under discussion? I do not even want to go there...

Tuesday, January 31, 2012

My experience with Binero 2.0 (so far...)

Well, for those who do not know, Binero is a Swedish Webhotel, which I use for a small site, and also administer another.

They brag about being "Best in Test" and having an awesome support all days a week through phone and email.

Well according to me, if they are best in test, how bad are the other ones? If the support are awesome, why is it impossible to reach them by phone, (if you do not want to be in a phone queue listening to some stupid 80's computer game melody forever)? And why does it take a full day to get an answer on a mail you send?

OneClick

They also lifts out their "OneClick" solution as you avoid sitting with long installations. However, it does not really work. And then you have to wait to get an answer from the support that does not really help.

In my example, I wanted to migrate my small site to 2.0 to be able to test Umbraco for the other site. Well to not think of the headache to migrate, which I will describe later, when finally migrated I tried to install it. Well did it work?

Not really. Trying to install Umbraco on the Windows platform, you have to choose domain and then application to install. Guess what! The only thing I can do, is to read the message that the chosen platform does not support this. Well, creating a subdomain for Linux instead, Umbraco is not an option anymore.

What does the support say, that I have to create the subdomain on Linux!

Ok, I did not actually write that it was Umbraco I was trying to install and since that should be on Windows. But after replying to the mail 21 hours ago, I still have not got any answer to why this does not work.

Migrating

Ok, back to the migration, which is a story it self.

I started it early myself, since this is an option. then it says, migration will start 24th at 10:49, then nothing happens, this is what I see when I log in. Then I sent a mail about this, and what I wrote and when I can not tell, because of later problems. Anyway, the support took their time to answer, like 6-8 hours. (Because calling is not an option "There is many calling right now....").

Reply was something like "We are sorry about this, but we can not give any estimations of how long it will take, but no longer then the end of next week"...

What!, can it take more than one week to move a -NET site with not that many pages? After a long time, at friday, I get a message that a technician will reply to me with a better answer. He did, monday, with the short note that it was stuck in a state that did not tell them it did not work.

Then the actual migration. For the site there was no problems actually. There was just ONE inconvenience. My mail address disappeared. I wrote the support about it (from another address), No reply at all, then I wrote after 6 hours, that this is bad, and maybe I should blog about it....Well when I got home, there was an account again. But all my old mails were missing, and still are. And Binero is all quiet, no reply at all on the task.

The ironi in this is that they are trying to take the customers from another webhotel, that had mail problems a while ago.

On top of it, in the migration an invoice that was already paid was copied as not paid to the new account.

Wednesday, October 19, 2011

Scala Stock Charts - part 6 some GUI things

I got a bit caught up in all the programming and finished up a few diagrams, then some refactoring and was able to remove a couple of hundred lines of code. The program now looks like this:


As you can see a lot have happened since the last pictures of the application. So here is some things.

Main part

The applications is build up around a main frame that contains the bar chart and some overlays. As you can see there is also some text fields and buttons. The upper part is to search stocks/indexes and also handle the overlays in the bar char. These fields and buttons are:

  • Search field to enter a search criteria to filter the instruments to search for.
  • Search button, to apply the search
  • A combo box, to show the filtered search result, and also choose the stock to view. This combo box listen to changes and updates the bar chart with the selected stock
  • Next there is a box to limit the range of the data. I have not introduced recalculation for splits and emissions so to have a possibility to handle to not show before these events, I added a box to filter away prices before this date part.
  • Next there is the intervals for the moving averages in the chart, default they are set to 5,20,50 but can be changed but have as most 3 different, but also as few as one. Default they are Simple Moving Average (SMA),
  • to change to Exponential Moving Average (EMA) there is a checkbox
  • to update changed settings for Moving averages there is a button "Update averages"
  • finally on the top there is a check box to switch on/off viewing of "Bollinger Bands"
In the bottom part there is buttons for additional chart types. these are the ones I picked as most interesting for me and they show some different aspect of the prices.
  • Stocastics (show how a stocks price is doing in relation to past movements)
  • RSI (shows how strong a stock is moving in the current direction)
  • Aroon (shows if a stock is trending or oscillating)
  • MACD (and also MACD-histogram) (a momentum oscillator)

As I mentioned the main part is a Bar chart diagram. It contains some overlays like volume, moving average and optional Bollinger bands. These help to get a basic overview of a stocks movement and trend. It is made up of a specialized panel for the bar chart to handle the drawing of the chart.

The main application implements a method named top that is used in wrapped Swing features used in Scala. I have an object representing my starting point of the application, the first lines looks like:
As you can see I provide a title and also here is the search field where to put a search string. The most important thing to note here is the inheritance of SimpleSwingApplication which makes this object a Swing application

The next part looks like this
Here you can see some on the fly declaration and reactions to events on the components.  The following code shows how to add these to the contents of other panels. you can also see the creation at the click of the button, creation of a generic diagram for "stochastics" mixed in with a DrawListener to make it drawable. Also how the series of stochastics is added to a generic diagram can be seen here.
This last part of the code adds the actual panels containing the fields, bar chart and buttons to the Swing application.

Additional panels

To add some extra check to the main part there is some diagrams that first was their own specialized panel, but after some refactoring they now all except MACD uses a generalized panel called GenericDiagram and here is a part of that code:

And here is addition of some of the buttons into menu panel (top panel) followed by some example of the bottom panel with addition of button and reactions to its event. You see here that here is where the panel frame is set up inside the reaction to show the GenericDiagram with "stochastic" data.
Not so much to mention really except that as you see I extend with a trait with basic chart properties. this is intended to have common properties for this and other diagrams. The var's is to be able to add series and date series to the diagram. So this panel is only responsible to draw the things that are sent to it.

Ability to draw

No bar chart is complete if it is not possible to draw some help lines. This is managed by adding a trait for this, that can be mixed in wherever I want it. The code for that trais is:
An example of this functionality is to draw help lines in a MACD diagram. (or any really)
This can be mixed in like in this case:
And then it is possible to draw on that panel.

Saturday, October 1, 2011

Scala stocks part 5 - Refactoring, big time

There is soooo much stuff that I would like to look in to. Alfresco, Liferay, GWT, Spring, Scrum, Agile etc. Right now though, I continue with my Scala project doing a Technical analysis tool for stocks using a Swing gui, also that with Scalas Swing libraries.

After working with the GUI, I started to get annoyed on myself mixing things up here and there, so I decided to refactor a bit. Actually, since I wrote the last post, I got a bit further then just plain refactoring. Simultaneously with the refactoring I worked on the GUI and also restructured code to finish up the loading of prices, enhancement of that loading and in that work I also managed to introduce some "Actors".

I will now also start to explain a little bit more what the code does.

I will split the refactoring and explanation in more than this post, otherwise I may get too long.

Refactoring of the FileHandler.
The new file is now much shorter, and includes only stuff to handle files. The extraction and transformation to the model is removed from the file handling. that messy code can be seen here http://ironicprogrammer.blogspot.com/2011/08/scala-stock-charts-part-3-saving-quotes.html if you have not already read it.

FileHandler.scala

In the start of the file, you see:
This is a companion object I use it to have a factory method. Maybe not really nescessary but at least I get away with not having to write
new FileHandler()
every time I need it and can use the shorter version
FileHandler()

The rest of the FileHandler should be quite easy to figure out. I have only one write-method where I send in the filename, if I want to append and a list of strings to write to the file. With this I can do all the saving I need.

There is also only one method for getting the file content (loadFile), this returns a list of strings which I later can traverse and to all the logic with.

I also have a method to have a format for how a price file is named. I do not want any blanks in the filename so this method is replacing that with "_" instead.

As you can see the FileHandler extends Logging. I do not need that here since no logging is going on in this class as it is now, but I can add it if I want. More about the Logging later.

Introducing PriceDAO.
To hide FileHandler from the rest of the system, and also to the mapping between files and model that was before done in the FileHandler, I introduced a DAO object to do the work. Doing this I can always change the way I persist later without too much impact on the code.

There is still some refactoring to do in this one since I have not changed the fact that I use mutable lists.
PriceDAO.scala

Some explanation maybe?

Well, I am not going into every line. I choose some parts that I think is interesting parts of Scala.

This code it possibly a good candidate to do some further refactoring on to try to make it immutable, but this is what is going on.

  • lists is mutable, because I need to add things in it, and I assume that I do not know what lists are coming in. (Even if they are pretty known from the file)
  • prices is a list of type List[PriceItem], this means that everything in that list is of something under type PriceItem but right now I am only interested in the types Price and PriceList
  • If it is a PriceList I know that a new price list is starting, I add this as a map key with an empty list as the map value.
  • The flow goes on and for every Price that comes up this is added in the current list.
The next chunk of interest...

Here is the loading of the price lists. I will sow you part of the file so you know what we are dealing with.
That is how it is saved. So seeinging that makes it easier to explain what the above code does.

  • first there is 2 "extractors", these are regular expressions. In Scala you can use the 3-qouted strings to make a regular expression just by putting .r after it. This expressions can then be used as types cases in pattern matching and is very powerful way to extract thing.
  • (""".*"listname": "(.+)",.*\s*""".r) is for extracting the name of a list. This matches on the line in the file beginning with any character and then "listname":
  • the next "extractor" is for matching an instrument. for convenience I write the file with a "ticker" on a new line to avoid complex regexps. So I only need to parse the file and match on these.
  • When matching a new list I put a new map entry with an empty list, and when hitting a "ticker" I just add that instrument in the current list. Similar to what is going on when saving them.
Major restruction of PriceLoad.
I more or less totally reworked the loading of the prices from the site they are available from

One thing I wanted to do was to use actors. Here is were I got loose on doing that. Well, thats a bit exaggerating since there is only one Actor involved here (and another one in the Logging) so not so big fuzz. Here is the code, and I get into some details after it.
PriceLoad.scala

This is an application object with a main method so it is available to run from the command line. What it does is to check if you enter with one or two arguments. Entering with one argument will load for one day. Entering with two arguments will run for a date span. I do not really car if there is days that does not have any prices, the only thing that will happen is that a FileNotFoundException will be logged.

The date span wil be recursively calculated to a list of strings with the method stringDateList.

After getting the list with dates, whether it is one item or more, I am traversing that list and sending a Daily object to an actor to do the loading and saving of that day. When all dates are handled I send a Stop message so the actor can exit itself.

Since I am sending to actors the flow of the program just passes to the end of the main method so I have to check the state of the actor before I do the exit. (There is a hang otherwise, because there is a thread that is still running somewhere.) and I do not want to do a sys.exit() before since that kills the thread that is loading.

The messages that is sent is case object/class that is defined like:

Other than the actor logic, the load and save is more or less the same as before. Just that now it is threaded and runs by an actor by sending messages to it.

Well, that was enough for this time. The GUI is more evolved also, but that is another story, another day. But a teaser to show how it looks so far:

Saturday, September 24, 2011

Scala stock charts, part 4 - Woking with the GUI - 1

I have been busy the last couple of weeks, or better saying, too lazy to sit home with my Scala Technical Analysis tool. Anyway, this weekend I decided to continue and this time to start from the GUI and start using the functionality done so far from a GUI.

I have also done som restructuring in the packages which now is:

package me.ironic.scabors.app
package me.ironic.scabors.service
package me.ironic.scabors.model
package me.ironic.scabors.file

even if I have not reworked the messy file-package. I will do that later. however, I finished up with loading the price list, and that code now look like this:


I also broke out the model classes from the file package, and put it in another file called PriceModel.scala, you can also see that I am now using "Price" which is a better name than "Quote" so all references to Quote is now replaced with Price. The content of that file is:

PriceModel.scala


I also made a Service object so that the GUI does not need to know or depend on anything from the file package. So far as I have gotten with the GUI it just contains two methods, one to get all price lists and one to get the data for a chosen stock. Here is the code:

PriceService.scala

GUI programming done in Scala

I decided to leave the idea of using Java FX that I had from the beginning and that I wrote in the beginning post. Instead I decided to use Scala Swing. Not so easy as it turned out, because first of all, it has been a couple of years since I last did any Java Swing programming and second of all, it was not very similar and not easy to transform Java Swing thinking to Scala Swing thinking. Well, it is less code, but surly, at this stage it looks really messy. Maybe it takes a while for my brain to melt Scala Swing programming and the fact that google got warm from all searching and few good examples does not help.

I am to tired to explain most of the code, maybe in a later post, but here is what the purpose if the GUI is so far.
  • Provide a text field to filter search for stocks "Instrument"
  • Provide a button to perform the search
  • Provide a ComboBox to present the filtered result from the search and to select stock to draw
  • Provide Panel for drawing a Bar Chart of selected stock

I have implemented and it works as I wand, except that the tedious job to provide the functionality to draw a bar chart is not done. Thea is a later exercise and a future post to describe. I let you see the messy code for this. 
ScaBorsApp.scala

Yeah, thats right, I also gave up SBT, I am now using gradle to build. here is the code for that. build.gradle
build.gradle

Until later..... ciao!