Writing a Class

Hi, can anyone help me out with this, this is what I need to do:
Write a Java class that represents a 2-dimensional array. It should include the following:
? class variables to represent the number of rows and columns
? a constructor that creates an N X N matrix
? a constructor with two parameters of type double specifying number of rows and columns
? three accessor methods that return 1) the number of rows, 2) the number of columns and 3) the total number of elements in the array
? a toString method that overrides the Object method with the same name, and returns a String representing the array in the following format:
[nrow: 10, ncol: 10] for a 10 X 10 array
Now i'm still very new to Java and i'm confused about a lot of this.
I have only written the 2 constructors so far:
public class array {
     public array(int N) {
          int[][] newarray = new int[N][N];
     public array(double rows, double columns) {
          double[][] newarray = new double[(int) rows][(int) columns];
}I'm not even sure if those are right.. Also, for "class variables to represent the number of rows and columns", I tried doing this for the variables rows and columns, but the compiler complained whenever I used them in the constructors.
Can anyone help me as to how to write the accessor methods and the toString method as well?
Thank you.

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Edited by: rsheal on Feb 23, 2009 10:37 PM

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Please help with writing a class

i need help getting started with this assignment. i haven't done anything with writing classes, so i don't know where to start.
i need to create a bank account class that will keep a name, balance, up to 50 deposits, and up to 50 withdrawls. i need to include 2 arrays for the deposits and withdrawls.
Here's what i know:
I need a constructor that takes zero arguments. This constructor would initialize the numeric value to zero.
I need a 2nd constructor that takes one argument, a name as a String value. This constructor would initialize the numeric value to zero.
I need a 3rd constructor that takes two arguments, a name as a String value and a starting "balance" as a double value

Sorry, I was watching a movie with my wife ...imagine that. Study my examples here and try to understand what I have done. You will follow the same methodology for the rest of the program. Use main to test the methods in your program.
public class mdlAccount {
String name;
double balance;
int currentDeposit = 0;
int currentWithdrawl = 0;
double[] deposits = new double[50];
double[] withdrawals = new double[50];
public mdlAccount() {
    name = "";
    balance = 0.0;
public mdlAccount(String name) {
    this.name = name;
    balance = 0.0;
public mdlAccount(String name, double balance) {
    this.name = name;
    this.balance = balance;
// When the instructor says: Have a method that does deposits...
// You need to create a method, similar to the constructors,
// but with a return value, even if it returns void (nothing).
// Like this:
public void deposit( double amount ) {
    // Do some error checking.
    if ( currentDeposit < 50 && amount > 0 ) { // > is a greater than sign
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      // and add the entry to the array of deposits
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      // Finally, add 1 to the currentDeposit variable.
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// We need the 'return the balance' method so we can see if
// the program runs correctly. This time we return a double,
// instead of void. (void means don't return anything at all).
public double getBalance() {
    return balance;
// Now you create the next method for withdrawals...
// if ( currentWithdrawl < 50 ) {
//    deposits[currentWithdrawl] = amount;
//    currentWithdrawl++;
// You want a main method so this class can be executed.
// You can remove it later if you want to use this class
// from within another larger program.
public static void main(String[] args) {
    mdlAccount acct = new mdlAccount( "GumB", 100.0 );
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    acct.deposit( 50.0 );
    System.out.println("Current balance is " + acct.getBalance());
}

Reading & writing binaries(.class files)

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Did anybody say anything about disassembling?He wants to read and write class files, it's the title of the post.
I don't appreciate you dismissing my suggestions like that.
There's plenty of gotchas in reading and writing class files, such as Longs & Doubles taking up 2 positions in the constant pool.
Hence the reason why I suggested using an open source library like BCEL or ASM. These are still valid as class readers, even if you don't touch the byte code. ( disassembly )
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Morning,
I've got a project using al least 4 jsp documents that try to manipulate a mysql database
To access the database and get a connection, i've put this syntax at the start of each document
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<%
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Message was edited by:
Octavian

This syntax reference JSP 2.0 : http://java.sun.com/products/jsp/syntax/2.0/syntaxref20.html
covers JSP actions such as jsp:useBean , jsp:getProperty and jsp:setProperty.
The API for JSTL is pretty intuitive:
http://java.sun.com/products/jsp/jstl/1.1/docs/tlddocs/index.html
But if you need more details on a particular JSTL tag you can refer to the JSTL 1.1 Specification - it's a PDF document.
JSTL also uses EL (Expression Language) which is also covered by the JSTL specification and by the above JSP 2.0 syntax reference.
There are many JSTL tutorials and articles too, but most of them are old so they contain JSTL 1.0 code.
To get yourself started you need jstl.jar and standard.jar which come with the latest JSTL 1.1 distribution found here:
http://jakarta.apache.org/taglibs/doc/standard-doc/intro.html
Standard-1.1 (JSTL 1.1) requires a JSP container that supports the Java Servlet 2.4 and JavaServer Pages 2.0 specifications. Jakarta Tomcat 5 supports the new specifications. The Standard-1.1 taglib has been tested with Tomcat 5.0.3.
After you have set up your environment you can test it with a small sample of JSTL code like this:
inside sample.jsp
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
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Flex with any ORM - Writing Model classes and action scripts redundant?

Hi,
I am using Hibernate with Flex. I have all my model classes
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Hi All
I am hoping that some out there can help me with this.
I have a lot of Dialogs that I what to open and close.
I am using the code to do that , and it works fine.
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PLEASE SOMEONE HELP ME .....................
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Why not simply create a method that wraps all the redundant stuff?
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}Then you could call it with all your various dialog types:
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Help writing a class

Trying to learn how to write a class. I had this AS for a
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I am doing what I think I need to, but am getting a bunch of
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My class starts like this and I am getting the following
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import mx.utils.Delegate;
class VideoPlayer extends MovieClip{
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Why is that and how do I get around that?
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Ah, I get it. Sorry totally new to classes and having some
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Writing a class "manual" in Pages ?

I have Pages 2 and as part of this semester at College I will have to write a "manual" which is to be around 40 or so pages long.
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Hello,
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I think its better to do the second example
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xyz.method3(args[2]);
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Greetings;
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          Cheers - Wei
          Hyung-Jin Kim <[email protected]> wrote in message
          news:[email protected]..
          > It seems that if I compile a class that a JSP uses while Weblogic is
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          > when the server is started again. Is there any way to turn this "class
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          >

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Ok. Sorry
Here is the main code
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InputStreamReader theReader = new InputStreamReader(theStream);
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Hello,
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Hi,
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Klaus

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