Java Language

Combobox change combobox which adds text in textArea

danger_dave — Wed, 28 Dec 2011 06:31:01 -0500

Hi, I have been scratching my head for a couple of hours wondering why my Japplet isnt working. The problem is, the second time I select the first combobox, the second combobox does not update its content and hangs. I am not sure where its looping to and have tried to trace it out. The code is as follows.

public class brake extends JApplet implements ActionListener {

JComboBox state, traintype;
Container c;

String[] sNSW = { "Select", "Titan", "HMT" };
String[] sVIC = { "Select", "Nokia", "Sony" };

TextArea display = new TextArea(10, 80);
String str;

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Ballistic Line help

mi_para — Fri, 16 Dec 2011 07:59:29 -0500

Okay so, here is what I have so far, I am constructing a program that will eventually take a user input angle and velocity and display the ballistic path of a notional projectile, sans friction and whatnot.

I have yet to build the user defined variables, I am just trying to get the polyline to display in the frame with a pre-defined angle and velocity. Somewhere down the road I would like to animate this, but for right now I am just trying to make it display on a Canvas.

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Core Java

How to manage a dbms with multimedia content in java - jdbc(client /server)

arunrajp — Mon, 07 Nov 2011 09:54:46 -0500

I am an old timer from the 90s so java7 is a bit of a shock to me as ima an SCJP for java 2 platform from 2000.

Please suggest the best way to manage a multimedia databse containg (*.jpg and *.au) files in a DBMS or RDBMS using JDBC for both client(Standalone java application) and server side(Servlets).

Enterprise Java

If else if else if else!!!!!

garnaout — Tue, 20 Sep 2011 15:15:44 -0400

I am parsing a string where the number of words is always changing. Since I have a minimum number of 1 word and max of 12 I wrote this function:

private void initializeParts(Scanner scanner) { if ( scanner.hasNext() ) // replace with a function/switch case for a better coding practice { part1 = scanner.next();


			if(scanner.hasNext())

			{

				part2 = scanner.next();

			}

			if(scanner.hasNext())

			{

				part3 = scanner.next();

			}

			if(scanner.hasNext())

			{

				part4 = scanner.next();

			}

			if(scanner.hasNext())

			{

				part5 = scanner.next(); 

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Avoid a cast when using class literals
bonzo101 — Tue, 20 Sep 2011 08:07:13 -0400
Hello. I have a question on java type safety.
I have a method that accepts a class literal and (for sake of argument) returns an instance of any class (in fact there is slightly more to it). 
Example:
Circle c = (Circle)this.returnInstance(Circle.class);

//removed exception handling
private Object returnInstance(Class c) throws Exception {

		return c.newInstance();

	}
My question is - is there any way to avoid performing the CAST (here, on the Circle instance) in the calling code?
Many thanks,

B
Core Java



'TIMER' Rule For Java Coding - Guidelines
hemal.shah — Thu, 15 Sep 2011 04:32:31 -0400
'TIMER' rules for Coding
Poor coding has always been nightmare for the project managers and development managers who are wholly resoponsible for the code delivery and are owners of the same.for many years there has been attempts made to educate the developer to follow the coding standards etc, but practically the coding standards in almost 70% of companies still stand the same. I hereby try to present rules that can be easily remembered by a developer while the person is doing the coding and can eventually check his code before delivery.
T – Testable Code 

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Inheritence problem(a demo form Thing in java)
ljjy23 — Sun, 07 Aug 2011 03:25:04 -0400
while reading Thinking in java, I get confused when I saw the example below(the example is in page 290, Chapter polymorphism):

public class PrivateOverride{
private void f(){print("private f()");}
public static void main(){
PrivateOverride po = new Derived();
po.f();
}
}
class Derived extends PrivateOverride{
public void f(){print("public f()")}
}


the result is private f();

I have two confusions: 

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Core Java



Newbie System.out.println
eclipse007 — Mon, 20 Jun 2011 09:10:25 -0400
Hi guys,
I’m Nick I’ve just joined the forum. Just wanted to say hello. I am pretty new to Java but have been teaching myself using books and the eclipse IDE. I know quite a lot about the syntax now and can write some pretty simple classes. I think I also understand classes, interfaces, inheritance and so on pretty well so think I’m well on my way. 
The thing I’m wondering is what the ‘out’ refers in: system.out.println(“something”) 
Usually you will have:

SomeClass.someMethod()

or

SomeClass.someMethod().someSubMethod().someSubMethod() etc… 

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Core Java



JavaOne 2011
t3chno — Tue, 19 Apr 2011 03:05:52 -0400
My development team is largely Java based. I am aware of Devoxx and would hope to attend next year, but what are the other conferences that would be useful for my requirements?
Mobile Java



methods
tesseract — Tue, 12 Apr 2011 21:49:42 -0400
take as given two classes : X and Y; where the main method is at X.
if i type a simple method at class Y, i am allowed to use it at X if and only if i create an object of the type Y while at X.  once i have an object of the type Y, i am allowed to issue a call to any particular method typed at Y given that i use the dot separator such that :
  y-object . nameofmethod();
 why is it that being at X, i can call a given method located at Y by means of an object of the class Y. 

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Community Discussion



how to print the attributes of an object
tesseract — Tue, 12 Apr 2011 21:38:36 -0400
i have a class by the name Veggie which extends Pizza; similarly, i have another subclass: supreme.  these are two different types of pizza.  
my constructor for Veggie declares an array such that the arguments specified by the constructor take the value of each particular element at the array.  for example:
  Veggie (String size)

  {

     String veg [] = new String [1];

     veg [0] = size;
   } 

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Community Discussion



QCon or Javaone ????
lisaantony06 — Thu, 24 Mar 2011 05:04:55 -0400
My company allows me to visit one international work related (I'm Java/JEE Developer/Technical Lead interested in polyglot programming) conference each year. I've visited Javapolis (devox) in the past.

For this year I'm looking for a conference which is less technology but a bit more methodology focussed... possible like Oracle Develop or QCon or Javaone What would you recommend?
Tools and Methods



File uri containing hostname
sudesh.ach — Wed, 16 Mar 2011 11:36:40 -0400
Hi All, 
The one of the valid form of file uri is of form "file://host/path". But with java 1.5 the File class is not able to handle the host part from the file uri. The File class makes a check for authenticator, if its exists it would throw exception . Is there any workaround for this ?. Any pointer will be of great help.
Regards

Sudesh
Tools and Methods



BASIC HELP WITH ARGUMENTS NEEDED
KKuykenda11 — Thu, 23 Dec 2010 19:40:10 -0500
So I swear I typed this in EXACTLY as the book told me but it still says I have an error at the "thread main".  Please help!
class BlankFiller {

    public static void main(String[] args) {

        System.out.println("The " + args[0]

                + " " + args[1] + " fox "

                + "jumped over the "

                + args[2] + " dog."

                );

    }

}
Community Discussion



Thrift Technology
shdhumale — Tue, 16 Nov 2010 08:55:19 -0500
Just want to share the new Technology info…… known as Thrift.
Thrift is a software framework for scalable cross-language services development. It combines a software stack with a code generation engine to build services that work efficiently and seamlessly between 
C++, Java, Python, PHP, Ruby, Erlang, Perl, Haskell, C#, Cocoa, Smalltalk, and OCaml.
Inshort !! now we can expose any method written in any above specified language and can consume it by creating client (again with any specified language)
One Billion $ Question !! How to use Thrift  

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An application which requires password to access its content
babz — Tue, 09 Nov 2010 14:29:27 -0500
Hi, 
I would kindly ask for help concerning my problem below. 
I want to develop a simple store management system. The system is supposed be developed as a distributed system that can handle multiple clients simultaneously

The solution should be based on RMI, where the user must be identified with the ID and password before a service is made available. 
I found it hard for me :(, as i am just a beginner. I appreciate for help ;) 
Thank you in advance
Community Discussion



Java subprocess issue *Novice*
Marker — Wed, 20 Oct 2010 13:53:15 -0400
Hi,
I am a novice Java programmer and am facing some issues. I have some piece of Java code which spawns off a python script. For a while, the script runs just fine but, then stops working all of a sudden. I thought it may be because I was not reading the output stream of the spawned script and hence changed the script to not produce any outputs. But still the script stalled. I am able to run this script externally (in a shell) with no problems for days but inside Java, it hoses up! 

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Core Java



Bluetooth Freisprecheinrichtung
randi420 — Thu, 14 Oct 2010 13:40:57 -0400
Die Hände gehören beim Auto fahren ans Lenkrad. Seit langer Zeit ist das Telefonieren mit dem Handy beim Auto fahren verboten. Das hat ganz sicher auch seinen Grund, denn viele Unfälle passieren gerade beim Telefonieren, wenn man auf das Display schaut. Trotzdem gibt es immer wieder Menschen, die es nicht sein lassen können. Dabei ist das Telefonieren mit einer Bluetooth Freisprecheinrichtung so einfach. Freisprecheinrichtungen haben genau wie die Handys inzwischen viele Funktionen. 

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Job Opening for J2EE professionals
chaku11483 — Tue, 14 Sep 2010 07:53:16 -0400
Dear Candidate,
We have urgent opening for Sr. Java Developer for our client in chennai
Experience: 4-8 Years
Work Location: Chennai
Skill Set: J2ee,Jsp,XML,HTML,Sql server
Job Description:
. Strong exposure to XML, HTML, JavaScript and AJAX.

. Strong experience on J2EE . Java 1.4, JSP 2.0, Servlets 2.4, JDBC, Struts 1.2,      Spring and Web services.

. Good exposure to ORM concepts and strong experience using Oracle TopLink or Hibernate ORM frameworks.

. Working experience in IBM RAD 6.x / RSA 7.0, WAS 6.x application server and any configuration management tool 

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Core Java



Print numbers in a matrix
gsxr600x — Fri, 03 Sep 2010 01:13:52 -0400
I'm playing around with 2D arrays and I'm trying to print random numbers in a 3 X 5 matrix. So far this is what I have:

class 2DArray{

   public static void main(String[] args){

   int[][] array = new int[3][5];
   double randnum = Math.random();
   
   for(int i=0; i<array.length; i++)
   {

      for(int j=0; j<array[i].length; j++)
      {   
         System.out.print("  " + i);
         System.out.println("  " + j);
      }
   }
}
}

I'm having trouble getting it to print in matrix form. Can anyone help me out?


Print numbers in a matrix
gsxr600x — Fri, 03 Sep 2010 01:11:02 -0400
I'm playing around with 2D arrays and I'm trying to print random numbers in a 3 X 5 matrix. So far this is what I have:
class 2DArray{
   public static void main(String[] args){
   int[][] array = new int[3][5];

   double randnum = Math.random();
   for(int i=0; i 

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Java To Html Convertor
togotutor — Fri, 13 Aug 2010 11:53:34 -0400
JavaToHtmlTest/Java2HtmlTest is a test program to display capabilites of togotutor's online tool for converting Java Code to HTML format. The generated HTML code can be pasted on any web page to display properly formatted Java Code. JAVA TO HTML by TOGOTUTOR
Tools and Methods



Using Eclipse IDE + Hello World example
lyeshassaine — Fri, 30 Jul 2010 19:55:45 -0400
If you're just getting started with Java, or want to know the basics of how to use an IDE such as Eclipse, then this is a great tutorial:
http://www.leolol.com/tutorials/java/java_hello_world_eclipse.html>


Location of properties file
somakd — Fri, 16 Jul 2010 04:56:24 -0400
I am trying to write a File copy program where the source folder and destination folder should be parameterised and will be present in a .properties file. User may change the value at runtime, and the effects should take place without recompilation. 
My question dis-regards to this program is - is this a good practice to leave out the properties file outside the jar/war file, so that user can freely edit that ? If so, why ?
Core Java



Educational Information
walterhanson3153 — Thu, 08 Jul 2010 12:41:24 -0400
As this information is educational so this site has been added to my RSS feed for later browsing. To know more about

marathon training

http://www.marathontrainingschedule.net

[ marathon training ]
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