First Java proggie

Hello,
Still learning and going through tutorials. However, I decided that the best way is to start a project once I get a bit more comfortable.
Anyhoo, my first project will be to build a handheld interface to our Point of Sale system. Strictly order entry, no management or advanced features that are available on the traditional POS workstations. The reasoning behind this is:
1. Well, I need to write one anyway.
2. I believe that in the process of writing this app, I will gain experience in using some of the more popular java classes although I'm not sure how the GUI stuff will work and whether I will have to use the Micro Java stuff.
3. I will be talking to a Firebird SQL backend so I will have to become familiar with JDBC and the Jaybird driver. I originally thought of building a middleware app for the Java clients to talk in Delphi, but I will probably decide not to since there would only ever be local users and I want to get experience using JDBC.
Q. Is handheld development restricted to using the micro java classes or does it depend on the platform? The micro java classes seem pretty limited.
Q. If I decided to use a middleware server app, I would want the data to be encrypted. I've read up a little on the crypto stuff in Java, but haven't noticed which algos are actually supported? Blowfish? AES?
Q. Any advice or links for further study and preparation would be greatly appreciated.
Thank again,
Lee

Pretty ambitious for a first project, Lee.Yeah, apparently so. Unfortunately, that seems to be the best way for me many times than not
Yes, start with JDBC. See if you can find a JDBC
driver for that Firebird database, generate an object
model and a schema, and see if you can get data back
and forth between them. I will have to do more research, but an article I ran across mentioned that J2ME doesn't support JDBC. The article is old so hopefully researching Sun's site will provide more inforamtion.
(http://tinyurl.com/xfdp)
If no JDBC, then I will have to write a middleware server in Delphi.
I've done nothing with the J2ME, so I don't know what
it can talk to. I'm no help there. If they can use
HTTP, I think it'd be interesting and fun to see if
you can have a hand-held and a browser talk to the
same servlet on the middle tier. THAT would be
impressive stuff.
Ha, writing the client side application would be quite enough for me as a start I think. Middle tier would be written in Delphi/Kylix (assuming I can't juse JDBC). I think I would have to write some kind of class/object that encapsulated the basic functionality of a dataset (or at least what I am used to using as a dataset in Delphi: First, Next, Prev, Last, EOF, PostChanges, etc) for use on the client side and post the changes (INSERTS/UPDATES) to the middle tier for execution against the database, remoting print notifications, etc.
Hmmm. Might have bitten off more than I can chew on this one, but that is fun of it, no?
Lee

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I cannot figure out how to do get the value of both text fields and mutliply them together when the botton is clicked. Here's my code:
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P.S. I'm using eclispe btw.

Your problem is related to your ActionListener.
public class foreground extends JPanel implements ActionListener
calculate.addActionListener(this);You have it set up so the Foreground panel is listening to the calculate button's clicks, but it's not doing anything with the clicks.
I would strongly suggest dropping the "implements ActionListener" bit and implementing a separate ActionListener, like so:
JButton calculate = new JButton("Calculate!");
ActionListener buttonListener = new ActionListener() {
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mohogany wrote:
Thanks to the kind help from everyone on this forum and some intensive labor for the last couple of months, I've finally given birth to my first Java application. I used Netbeans as my IDE of choice. During the development stages I would run my project directly from the IDE. In the project folder, a total of five folders were created: build, dist, nbproject, src, and test as well as two files build.xml and manifest.mf.
Being a newbie in this field, I was wondering about the remaining steps needed to distribute the application. Here are some questions that come to mind:
1) I know I can simply just double-click the project's *.jar* file to get it work. Is that the norm with Java applications or do I need to create a different file? I'm used to seeing *.exe* files. I'm also used to seeing an installation process, which brings me to my next question.It's quite common to provide a shell script (batch file, etc) to launch the app.
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3) Seeing that I've only been testing the application in Netbeans, will there be file path or classpath problems if I run it on other computers? Are there necessary steps I need to follow to avoid such problems?Probably. The best way to avoid them is to test them, and to not ever depend on the CLASSPATH environment variable. That's a portability nightmare.
4) Do you take any precautionary steps to protect your code? Do you lock the folders? Nope.
5) In the future, if I decide to add a small fee to download the application, how hard would it be to add a password activation feature? (I know this could get pretty complex) Don't bother. Unless you've got something amazing, in which case you'll be needing lawyers, it's not worth the trouble of charging for it. No offence, but your first Java app is hardly going to set the world on fire anyway.
No matter what you try and do to stop people stealing your code, they'll manage it. Or, alternatively, just steal your idea instead.

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Right now, my opinion in java is that it's too
complicated for no reason compared to C++..It's not too complicated, it's just that you are new at this.
Here's a little example of a simple class with a simple main method, the rest figure it out yourself, and with time read some java books, you won't learn java just by knowing C++.
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Hi,
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hi,
Just do this,
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set PATH=%PATH%;E:\j2sdk1.4.1_01\bin
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doesn't requires classpath to be set, your system classpath variable needs a DOT (.)
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Regards
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Could anyone give some tips for going from graduate
(BSc Comp Sci) to getting first java job? A lot of
employeers want 'experience' but when you've just
graduated you've only ever worked on uni assignments
and not industrial ones. How do you crack this?
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Otherwise, persevere or move to India (they seem to hire anyone who can spell the word 'computer' there).
Does certification impress anyone other than
recruitment consultants?
Depends on the certification but in general yes.
It impresses not the recruitment consultants but the non-technical people they're selling you to.
Anyone with a grain of knowledge about certs will know that most if not all are completely useless without practical experience to back them up (and some worse than useless, think MCSE NT4 which was a disaster).
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Friends,
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Hello all,
I'm new to this forum (just joined today) so hi! I've been learning java for the last few months by reading a few books, and finally decided to take a crack at my first program (beyond hello world). This one is windows only. At work with a co worker we found that in windows 2000 the background images could get out of sync, so this program gives the user an alternative way to set the backgrounds.
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Here's a link to my jar:
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Will

Right now, my opinion in java is that it's too
complicated for no reason compared to C++..It's not too complicated, it's just that you are new at this.
Here's a little example of a simple class with a simple main method, the rest figure it out yourself, and with time read some java books, you won't learn java just by knowing C++.
public class Human {
    // See this as C constants (although they're not their Equivalent)
    public static boolean MALE = true;
    public static boolean FEMALE = false;
    //member variables.
    private String name;
    private boolean sex;
    /** Creates a new instance of Human */
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        sex = s;
    }//End of CONSTRUCTOR.
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    }//End of toString()
    //Just the main program, it could be at another class.
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}//End of class

First Java proggie

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