Core Java

Exception in thread "main" java.lang.IndexOutOfBoundsException:

John00000000 — Thu, 07 Mar 2013 16:16:43 -0500

import java.io.*;
import java.util.ArrayList;
import java.util.*;
import java.io.IOException;
import java.lang.*;
import java.io.RandomAccessFile;

public class ArrayListClass {

public static void main(String[] args) {

ArrayList integerArrayList = new ArrayList();
ArrayList integerArrayList2 = new ArrayList();
ArrayList integerArrayList3 = new ArrayList();
ArrayList byteArrayList = new ArrayList();

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Tools and Methods

How to use Emma code coverage in jdk1.7?

ILLA — Thu, 14 Feb 2013 04:06:54 -0500

Recently i moved jdk1.6 to jdk1.7.Emma code coverage tool working fine in jdk1.6.but It did not working in jdk1.7.It throws following error.

emma:
[emmajava] EMMA: no coverage data collected at runtime [all reports will be empty]
[emmajava] [EMMA v2.0, build 5312]
[emmajava] emmarun: [MAIN_METHOD_NOT_FOUND] application class does not have a runnable public main() method
[emmajava] Exception in thread "main" com.vladium.emma.EMMARuntimeException: [MAIN_METHOD_NOT_FOUND] application class does not have a runnable public main() method

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Tools and Methods

Server Side Developers

dmottilloMDT — Wed, 13 Feb 2013 15:35:25 -0500

Lately I have been seeing several of my clients look for Java Developers that have "Server-Side/Core Java" development experience. I was under the impression that meant they wanted people who have worked with Servlets and JSP. Apparently I was wrong. Can someone out there school me a little on what I should be looking for in someone that has server side development expertise? Thanks! Dominic

Tools and Methods

Why logger as singleton

JavaLearner — Thu, 31 Jan 2013 02:36:03 -0500

Could there be any issue other than performance if my logger is not singleton.
In case of cahce objects it makes sense to have it as singleton as we may need to refresh the cache at times but why should we have logger as singleton.

Core Java

Times 5 Calculator

ThomasFike — Thu, 24 Jan 2013 06:01:41 -0500

This Is my first program and is basic and I know that I hope you still it.
My Bio: I am 12 and love to develop and have ben doing different langues off and on for the past 4 years or so.

Download:http://www.mediafire.com/?03b9jdl902vjy4f

Core Java

AJAX in jsp with Database

g9848921789@gmail.com — Sun, 20 Jan 2013 09:00:46 -0500

hi friends,
I am doing project in jsp with database. in my jsp page one textbox is there. when ever use enter the customer name it will display the related names like autocomplete textbox (like google search bar). in this i want use ajax . but its wondering i donot know how to use i referred number of websites. plz..... help me some body. i have "ajaxanywhere.jar file". but i donot know how to use plz.... provide solution with ajaxanywhere.jar file or any another way.

thanks in advance

Tools and Methods

How to write a automation code in Java ?

iKrrish — Mon, 07 Jan 2013 09:01:16 -0500

Hi Team,

I have been writing a automation code for testing the API provided by company. Initially, there were few number of APIs but when our features and enhancement grows, API also grows.

Now my automation code looks complex and messy. I need to revamp my automation.

Brief intro to my automation:

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Tools and Methods

Objects and reference variables of different types

vabbs — Wed, 12 Dec 2012 23:54:47 -0500

//for example only
class A
{}
class B extends A
{
 public static void main (String [] args)
 { 
  A a1 = new A(); 
  A a2 = new B();  //my doubt lies here
  System.out.println(a1);
  System.out.println(a2);
 }
}

When it is declared as "A a1 = new A();", object is created to class A and 'a1' refers to the newly created object.

But, when it is declared as "A a2 = new B();", what does it imply? I am confused why should a class B object be referred by reference variable of A ?

I request to help me making this concept clear, please.

Core Java

Printing date in java, format : 21st November 2012

ganesh_rdy — Mon, 26 Nov 2012 13:14:21 -0500

You are required to write a Java class, called Date, that can be used to represent dates.
The date object should be represented as three integers for day, month and year. The year must be stored in full, example, 2004 and not 04.
Provide appropriate constructors, get() and set() methods for day, month, year. getYear() should return the year in full ( 1998, 2004 etc. ) and getMonth() should return a String representing the name of the month. Finally, you should provide a toString() method that returns a String representation of the date in full, for example,
22nd December, 1999

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Community Discussion

Any good resources for the Java concurrency API?

ganapathy.c — Tue, 02 Oct 2012 10:29:13 -0400

Core Java

Error 500: java.lang.NullPointerException

midani — Wed, 15 Aug 2012 14:30:56 -0400

Hello I am working on this servlet, it is a Context.java servlet in the /lib folder of my project, which I inherited from another developer. We have been making a lot of changes to the .xsl and .xml, however, it appears to be throwing an exception right here:

void getDisplayLifeReviewForHome() {
System.err.println ("Can't Find Display Life Review for Home !!! " );

}

void getDisplayLifeReviewForUser() {
System.err.println ("Can't Find Display Life Review for User !!! " );

}

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Community Discussion

JAVA insert chinese character

snufkin — Sun, 05 Aug 2012 21:44:05 -0400

When I use below statement to insert chinese character. It is store '????' into database.

try{
ps=conn.prepareStatement("insert into Arn_Web_LabourRpt_Details " +
" (RequestId, InsLineNo, Description, Location, OrderNo, LabourNo, JobDate," +
" Leader, ReportNo, Product, OK, Rejected, MDNo, Address, PerferenceLabour, ActualLabour, ConfirmationStatus," +
" LastUpdateDate,LastModify,ProjectName) " +
" values (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,getdate(),?,?)");
ps.setInt(1,RequestId);
ps.setInt(2, this.getInsLineNo());

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Core Java

error in execution of class

kk — Tue, 31 Jul 2012 15:26:23 -0400

The syntax of class execution is :
java classname
why there is an error when I execute class with its extension i.e.
java classname.class
error- no main class found

Tools and Methods

why only dynamic allocation?

kk — Tue, 31 Jul 2012 15:22:18 -0400

Java has evolved from c++.C++ has got both dynamic and static memory allocation i.e. objects can be made without using new keyword in c++.My query is why static object creation removed in java and only oject creation using new is there?

Tools and Methods

Singleton Design Pattern. All flavours explained.

CentralAdvisor — Sun, 29 Jul 2012 09:18:22 -0400

Hi!
This design pattern is used for controlling the number of instances of a class (to one in general). This is maybe the first, the most used and the easiest design pattern out there.

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Tools and Methods

Print Excel File using Printer

S.Manikandan — Tue, 26 Jun 2012 01:40:14 -0400

Hi,
I am in tricky situation. I need to print an excel without open that file.
How to achieve this.

by,
Manikandan.S

Tools and Methods

At commands

diksha — Tue, 12 Jun 2012 14:10:53 -0400

can we make a code in core java for usb data transfer in which At commands is also using??

Tools and Methods

Creating a new PrintService with IP address of the Printer

joancloud — Tue, 05 Jun 2012 07:27:50 -0400

Generally a PrintService will be looked up like in the below snippet

PrintService defaultPrintService = PrintServiceLookup.lookupDefaultPrintService();
DocPrintJob printerJob = defaultPrintService.createPrintJob();

But is there a way to create a new PrintService by specifying the ip address of the printer

for eg:

String myPrinter = "10.101.111.11\\Eighth Floor Ricoh Printer";

PrintService myPrntSrvc = create a service with myPrinter

printJob.setPrintService(myPrntSrvc);

Enterprise Java

Saving JFrame to Image File

compumaster — Wed, 30 May 2012 16:54:36 -0400

Hi All,

I would like to save an (invisible) JFrame into an image file (jpeg).In other words, I only want to save the drawing to an image file without displaying it to the users.

I tried:

BufferedImage image = new BufferedImage(frame.getWidth(), frame.getHeight(),
BufferedImage.TYPE_INT_RGB);
Graphics2D graphics2D = image.createGraphics();
frame.panel.paint(graphics2D);
ImageIO.write(image,"png", new File("image.png"));

But this only works with a visible frame (frame.setVisible(true))

Any thoughts?
Thanks a lot.

Core Java

Array of Char's

tariq — Thu, 24 May 2012 09:04:10 -0400

Hi All,
I am having difficulty to understand the difference between:

char [] myOriginalArray = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i'};
and

char [] myOriginalArray;

myOriginalArray = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i'};

Why eclipse wont compile the second but will compile the first one.........
both are exactly the same to me.
any thought????

Tariq

Core Java

Email validation

sabitha — Fri, 04 May 2012 14:11:57 -0400

Hi ,

Can anyone guide in working on this project.When a user creates an email on a website,it should redirect to his/her email id for validation.

Thanks,
Sabitha

Core Java

Touch on dynamically generated images

razib_mahamud — Fri, 04 May 2012 03:00:12 -0400

I have dynamically created a grid of 8x8 image views . Now how can i handle the touch events on it. Though i am able to handle the touch on more than one image view when made from XIB but here when i dynamically created those image view, touch is not working on it.

Please help me in this.
Waiting for the reply.
http://www.mobilecoolrooms.com

Tools and Methods

Can someone help us with getting Google Page Ranks.

petersonlee.cc@gmail.com — Fri, 13 Apr 2012 17:51:39 -0400

Can someone help us with getting Google Page Ranks.

We use to run code to get a few thousand Google Page Ranks each day.

But now Google stops our application by asking us to input the image code, trying to make sure we are not a bot.

We know other companies are still collecting Google Page Rank but we can't get ours working.

Can someone show us the way to read the image?

Or suggest a work around so we can once again collect our Google Page Ranks?

Thank you,

Billy

Core Java

Design class structure

javaworld-user1 — Thu, 05 Apr 2012 22:00:47 -0400

Hi,
I have less experience in java designing. In one of the interviews I have been asked a question which is like ,Design/provide a java solution for the expression '(a+b)*(a-b)-c' ?

I went explaining that we could create classes like Operators,Operands and Expression and saying that the class Expression would be having Operators and Operands and child expression.

Any suggestion how to visualize the real time problem in terms of java.For example for the above question whether to make the class abstract/or have an interface and so on?

Core Java

Interfaces

tariq — Thu, 05 Apr 2012 14:13:55 -0400

What is the an Interface in java?
What is the best way to understand an Interface in Java?

Input From all the members are welcome.............

Community Discussion