Need help with basic program.....!

I've to write a program that generates a random
number, which the user has to try and guess, after
each guess they're told whether it's too high or too
low etc., I've gotten this far, however, the user has
only 10 guesses.... In my program I've used a while
loop and the user gets an infinite number of guesses,
I know I'm supposed to use a for loop, but can't seem
to get it to work properly. Also, when the user
guesses the number, the program then has to print out
how many guesses it took, and I have no idea how to
get it to do this AT ALL!!! I'd really appreciate some
help with this, thanks v. much!!!!Hey not every book covers every aspect of Java (if you haven't got a book and don't want to buy 1 i recommend an online tutorial) If u want the user to have an infinate number of guesses, use an infinate while loop. Put this in a file called app.java:
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class app extends Applet implements ActionListener
     JLabel lbl=new JLabel("Guess a number between 0 and 10:");
     JTextField txtfield=new JTextField(20);
     JButton button=new JButton("Guess...");
     JLabel lbl2=new JLabel();
     int randomnumber=Math.round((float)Math.random()*10);
     public void init()
          add(lbl);
          add(txtfield);
          add(button);
          button.addActionListener(this);
     public void actionPerformed (ActionEvent e)
          String s=new String("");
          s+=randomnumber;
          if (e.getSource().equals(button) && txtfield.getText().equals(s))
               setBackground(Color.white);
               setForeground(Color.black);
               lbl2.setText("Got it!");
               add(lbl2);
               validate();
          else
               setBackground(Color.white);
               setForeground(Color.black);
               if (Integer.parseInt(txtfield.getText())>randomnumber)
               lbl2.setText("Too High!");
               else
               lbl2.setText("Too Low!");
               add(lbl2);
               validate();
Then create a HTML document in the classes folder:
<HTML>
<HEAD>
<TITLE>APPLET</TITLE>
</HEAD>
<BODY>
<HR>
<CENTER>
<APPLET
     CODE=app.class
     WIDTH=400
     HEIGHT=200 >
</APPLET>
</CENTER>
<HR>
</BODY>
</HTML>
It will do what you wish. If you want to have more then 10 numbers to guess, for example 100, do this:
int randomnumber=Math.round((float)Math.random()*100);
Does that answer your question?

Similar Messages

Need help with basic program - I am new to this

I need to write a very basic code to display my name on the screen as follows
RR OOO
R R O O
R R O O
RR O O
R R O O
R R OOO etc etc etc
to spell out robert
i have no idea where to begin

You need to store the patterns for each letter of the alphabet somewhere - say in an array. You can then read out the patterns to build up strings.
For example:String[][][] letters = new String[][]
{ {"A", " A " ... },
{ "R", "RRRR", "R R", "R R", "RRRR", "R R", "R R"},
}

Need help with inventory program!!! someone please help me!!!

Ok I have to write this inventory program for one of my classes.
For part one i needed to Create a product class that holds the item number, the name of product, the number of units in stock, and the price of each unit.
Then create a java application that displays all of the above info plus the total value of the inventory. I have done this so far with success.
For part two i needed to modify the program so the application can handle multiple items. Use an array to store the items. The output should display the information one product at a time including the item number, the name of the product, the number of units in stock, the price per unit, and the value of the inventory of that product. In addition, the output should display the value of the entire inventory.
so create a method to calculate the value of the entire inventory.(i did this)
and create another method to sort the array items by the name of the product. ( i did this)
The program compiles and runs fine except it is not doing anything from part two. It just does the same thing that it did when i wrote part one.
Does anyone know why or what i need to do to my code.
Here is my code.
import java.util.Scanner; // program uses class Scanner
import java.util.Arrays;
class ProductList
Product[] products = new Product[100]; // an array of 100 pruducts
private void populate() {
    products[0] = new Product(0, "Good Luck Chuck"      , 25, 4.95);
    products[1] = new Product(1, "The Bourne Identity" , 3, 7.95);
    products[2] = new Product(2, "The Reaping"          , 5, 8.99);
      products[3] = new Product(3, "Deja Vu"              , 2,12.99);
      products[4] = new Product(4, "I Know Who Killed Me" , 3,10.95);
private void sortByTitle() {
private void print() {
    for(int i=0; i<products.length; i++) {
      System.out.println(products);
private void printTotalInventoryValue() {
System.out.println("Total Inventory Value = "+calculateTotalInventoryValue());
private double calculateTotalInventoryValue() {
double total = 0D;
for(int i=0; i<products.length; i++) {
total += products[i].calculateInventoryValue();
return total;
public static void main( String args[] ) {
ProductList list = new ProductList();
list.populate();
list.sortByTitle();
list.print();
list.printTotalInventoryValue();
} class Product
private int id;
private String title;
private int stock;
private double price;
public Product(int id, String title, int stock, double price) {
setId(id);
setTitle(title);
setStock(stock);
setPrice(price);
public int getId() { return this.id; }
public void setId(int id) { this.id = id; }
public String getTitle() { return this.title; }
public void setTitle(String title) { this.title = title; }
public int getStock() { return this.stock; }
public void setStock(int stock) { this.stock = stock; }
public double getPrice() { return this.price; }
public void setPrice(double price) { this.price = price; }
public double calculateInventoryValue() {
return getStock() * getPrice();
public class Inventorypt2
private String ProductInfo; // call class product info
public static void main(String args[])
//create Scanner to obtain input from command window
Scanner input = new Scanner( System.in );
int num; // product's item number
int stock; // number of items in stock
double price; // price each of item
ProductInfo product; // product information instance
System.out.println(); // blank line
String name = "go";
// loop until sentinel value read from user
while ( !name.equalsIgnoreCase ("stop") )
System.out.print( "Enter DVD title, or STOP to quit: "); // prompt
name = input.nextLine(); // read item name from user or quit
System.out.print( "Enter the item number: "); // prompt
num = input.nextInt(); // read item number from user
while ( num <=0 ) //loop until item number is positive
System.out.println ("Item number must be positive. Please re-enter item number: ");//prompt user to re-enter item number
num = input.nextInt(); // read item number
} //end while
System.out.print( "Enter the quantity in stock: "); // prompt
stock = input.nextInt(); // read stock quantity from user
while ( stock <0 ) //loop until stock is positive
System.out.println ("Quantity in stock can not be less than zero. Please re-enter the quantity in stock: ");//prompt user to re-enter quantity in stock
stock = input.nextInt(); // read stock quantity from user
} //end while
System.out.print( "Enter the price of DVD: "); // prompt
price = input.nextDouble(); // read item price from user
while ( price <=0 ) //loop until price is positive
System.out.println ("Product price must be positive. Please re-enter the price of the product: ");//prompt user to re-enter product price
price = input.nextDouble(); // read item price from user
} //end while
product = new ProductInfo( num, name, stock, price); // initialize ProductInfo variables
System.out.println(); // blank line
System.out.printf( "Item Name: %S\n", product.getName());
System.out.printf( "Item Number: %s\n", product.getNum());
System.out.printf( "Qty. in Stock: %s\n", product.getStock());
System.out.printf( "Price Each: $%.2f\n", product.getPrice());
System.out.printf( "Total Value in Stock: $%.2f\n", product.getInventoryTotal());
System.out.println(); // blank line
System.out.print( "Enter DVD title, or STOP to quit: "); // prompt
name = "";
while ( name.equals("") )
name = input.nextLine(); // read new product name from user or quit
} //end while
System.out.println(); // blank line
System.out.println("Good Bye!"); // exit message
Edited by: jay1981 on Mar 16, 2008 2:07 PM

You will get more help if your code is formatted better:
* Only post code that is already formatted correctly including indentations.
* Get rid of all those comments cluttering up your code.
* Make sure your posted code compiles without need for any changes. Yours doesn't at present. Where is the ProductInfo class?
Again, you want it easy for a volunteer here to read your post, otherwise he/she simply won't do it. Good luck.

Need help with basic Java programming

I'm having a little bit of trouble with my code. For the sake of argument, I've removed the code I'm having trouble with, because I know it was inaccurate. I'm trying to create a loop so that this program will keep going through and through until the user enters an invalid variable. I thought the default after the case statements was supposed to make the system exit and output my message. Those two problems, the loop and the default, are what I'm really having problems with. My code is posted below.
import javax.swing.JOptionPane;
import java.util.Locale;
import java.text.NumberFormat;
public class Retail
public static void main(String args[])
String firstNum;
String secondNum;
String result;
int prodNum; //first number to input
double quantity; //second number to input
double total = 0.0; //total of Prod * Quantity Sold for all items
// To use American Dollar
NumberFormat moneyFormat = NumberFormat.getCurrencyInstance( Locale.US );
// first number entered as string
firstNum = JOptionPane.showInputDialog( "Enter product number 1-5" );
// second number entered as string
secondNum = JOptionPane.showInputDialog( " Enter quantity of items sold" );
// convert values to type double or int from type string
prodNum = Integer.parseInt( firstNum );
quantity = Double.parseDouble( secondNum);
result="";
if ( prodNum >=1 && prodNum <=5 ) {
switch (prodNum)
case 1: // 1st product
total = 2.98 * quantity;
break;
case 2: // 2nd product
total = 4.50 * quantity;
break;
case 3: // 3rd product
total = 9.98 * quantity;
break;
case 4: //4th product
total = 4.49 * quantity;
break;
case 5:
total = 6.87 * quantity;
break;
default: JOptionPane.showMessageDialog( null, "Wrong product number entered" );
JOptionPane.showMessageDialog( null, moneyFormat.format(total), "Total Price of Items Purchased", JOptionPane.INFORMATION_MESSAGE );
System.exit(0);
***I know I need to put something in the user input message to state that any value other than 1-5 entered will cause the program to skip to the output, I'll put that in later.***

When you post code, please use [code] and [/code] tags as described in Formatting Help on the message entry page. It makes it much easier to read and prevents accidental markup from array indices like [i].

I also need help with a programming assingment. I think I'm almost there!

I have the following assingment to complete:Once again, you realize that you need to upgrade your Java program with two more features:
Be able to print products which are �On Sale�.
Use arrays to store the product names so that you can keep track of your inventory.
After some analysis, you notice that printing the products can be achieved by modifying the two classes you have already written. One approach would be to add a Boolean attribute called �OnSale� to the ToddlerToy and add a print method that print information about a product indicating if it is �On Sale�.
Update your constructor, taking into account the �On Sale� attribute.
Create two more instances: a small train called Train4 and a big train called Train5. Mark both trains �On Sale�
Add another method that prints the sale information
Keeping track of the names of products can be achieved by declaring an array of strings in the ToysManager class itself. Each time a new product is created, it is also added to the array. Use a while construct to print the product names in your inventory.
This is the code I have come up with:
public class ToysManager {
     private String toyInventory[] = {"Big Train","Small Train"};
     public void printInventory() {
     System.out.println("List of Items in Toy Inventory");
     for (int i=0; i<toyInventory.length; i++)
     { System.out.println(toyInventory[i])); } // ";"expected - ToysManager.java
     public static void main(String[] args) {
          //System.out.println("This is the main method of class ToysManager.");
          //call on ToysManager printInventory method for a listing of all toy types
          printInventory();
          // Create ToddlerToy Objects Train1,Train2,Train3,Train4,Train5
     ToddlerToy Train1 = new ToddlerToy(489, "Big Train", 19.95,false);
     Train1.printOnSale();
     ToddlerToy Train2 = new ToddlerToy(489, "Big Train", 19.95,false);
     Train2.printOnSale();
     ToddlerToy Train3 = new ToddlerToy(477, "Small Train", 12.95,false);
     Train3.printOnSale();
     ToddlerToy Train4 = new ToddlerToy(477, "Small Train", 12.95,true);
     Train4.printOnSale();
     ToddlerToy Train5 = new ToddlerToy(489, "Big Train", 19.95,true);
     Train5.printOnSale();
}     //this is the end bracket for the main method
}          //this is the end bracket for the ToysManager class
class ToddlerToy {
     // Initialize and Assign Data Types to each Variables
     private int productID;
     public String productName;
     public double productPrice;
     private boolean onSale;
public void ToddlerToy(int a, String b, double c, boolean d) {
     // Assign Data to Variables
     productID = a;
     productName = b;
     productPrice = c;
     onSale = d;
     //PrintProductPrice(ProductPrice);
     } //end of constructor
public void printOnSale(){
     if(onSale == true) System.out.println("This item #" + productID + ": " + productName + "is on sale");
I don't have any problems with class ToddlerToy. I can compile that with no problems. I'm having issues with public class ToysManager. I can't compile that one correctly. It fails at:
{ System.out.println(toyInventory[i])); } // ";"expected - ToysManager.java
I've looked through the java books I have and also online, but I can't figure this out. I'm new to java so any help would be appreciated.
Thanks in advance.

Thanks. That got me past that error. I was hung up on that for far too long. I made some changes and when i compile the ToysManager class it shoots a different error. The code now looks like this:
public class ToysManager {
     private String toyInventory[] = {"Big Train","Small Train"};
     public void printInventory() {
     System.out.println("List of Items in Toy Inventory");
     for (int i=0; i<toyInventory.length; i++){
     System.out.println(toyInventory);
     public static void main(String[] args) {
          //System.out.println("This is the main method of class ToysManager.");
          //call on ToysManager printInventory method for a listing of all toy types
          printInventory();
          // Create ToddlerToy Objects Train1,Train2,Train3,Train4,Train5
     ToddlerToy Train1 = new ToddlerToy(489, "Big Train", 19.95,false);
     Train1.printOnSale();
     ToddlerToy Train2 = new ToddlerToy(489, "Big Train", 19.95,false);
     Train2.printOnSale();
     ToddlerToy Train3 = new ToddlerToy(477, "Small Train", 12.95,false);
     Train3.printOnSale();
     ToddlerToy Train4 = new ToddlerToy(477, "Small Train", 12.95,true);
     Train4.printOnSale();
     ToddlerToy Train5 = new ToddlerToy(489, "Big Train", 19.95,true);
     Train5.printOnSale();
     }     //this is the end bracket for the main method
}          //this is the end bracket for the ToysManager class
I get an illegal start of expression for:
     public static void main(String[] args) {
and ";" expected for:
     }     //this is the end bracket for the main method
I looked over my initial code, before the "for" loop?, and the public static void main was a valid statement.

Need help with inverter program

I am very new to labview and I need a lot of help fast. I have been given this vi program, which I have attached, that operates a bunch of inverters. The program is driving the inverter which in turn drives the agitator on a washing machine. The agitator goes in forward and reverse direction as a result of a relay within the inverter being supplied voltage to make it open and close. I need to supply voltage to the relay to make it go forward, reverse, and the pause before the next cycle begins. The current program has it doing a forward reverse and then immediately starts the next cycle. If any one can take a look at this program and let me know, first of all what the heck is going on, and second how to fix my problem, that would be incredibly helpful to me. If anyone has trouble opening the file let me know, I think attaching the vi should work but it may also look for a dll file or something when trying to open. Email me if you cannot open the file and I will send you the dll file as well. Your help is greatly appreciated. Thank you very much.
Tony
Attachments:
main2.vi ‏162 KB

Hello Tony,
you programmed it to run continously...
After the timed while loop runs through your array of ramp values you start again at index 0 (upper shift register). Instead of this end this while loop by combining the output from the comparison with your stop2 button (end loop when stop2 OR end of arrray). Now it will work.
Btw. why do you use "Insert to Array" when you want to concat 3 arrays (sequence frame 0)? Just use a "Build Array" and set "Concat Inputs" via mouse right-click.
Best regards,
GerdW
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

New to Java and need help with this program..please!

I'd really appreciate any helpful comments about this program assignment that I have to turn in a week from Friday. I'm taking a class one night a week and completely new to Java. I'd ask my professor for help, but we can't call him during the week and he never answers e-mails. He didn't tell us how to call from other classes yet, and I just can't get the darn thing to do what I want it to do!
The assignment requirements are:
1. Change a card game application that draws two cards
and the higher card wins, to a Blackjack application
2. Include a new class called Hand
3. The Hand class should record the number of draws
4. The application should prompt for a number of draws
5. The game is played against the Dealer
6. The dealer always draws a card if the dealer's hand total is <= 17
7. Prompt the player after each hand if he wants to quit
8. Display the total games won by the dealer and total and the total games wond by the player after each hand
9. Display all of the dealer's and player's cards at the
end of each hand
10. Player has the option of drawing an additional card after the first two cards
11. The Ace can have a value of 11 or 1
(Even though it's not called for in the requirements, I would like to be able to let the Ace have a value of 1 or an 11)
The following is my code with some comments about a few things that are driving me nuts:
import java.util.*;
import javax.swing.*;
import java.text.*;
public class CardDeck
public CardDeck()
deck = new Card[52];
fill();
shuffle();
public void fill()
int i;
int j;
for (i = 1; i <= 13; i++)
for (j = 1; j <= 4; j++)
deck[4 * (i - 1) + j - 1] = new Card(i, j);
cards = 52;
public void shuffle()
int next;
for (next = 0; next < cards - 1; next++)
int rand = (int)(Math.random()*(next+1));
Card temp = deck[next];
deck[next] = deck[rand];
deck[rand] = temp;
public final Card draw()
if (cards == 0)
return null;
cards--;
return deck[cards];
public int changeValue()
int val = 0;
boolean ace = false;
int cds;
for (int i = 0; i < cards; i++)
if (cardValue > 10)
cardValue = 10;
if (cardValue ==1)     {
ace = true;
val = val + cardValue;
if ( ace = true && val + 10 <= 21 )
val = val + 10;
return val;
public static void main(String[] args)
CardDeck d = new CardDeck();
int x = 3;
int i;
int wins = 1;
int playerTotal = 1;
do {
Card dealer = (d.draw());
/**I've tried everything I can think of to call the ChangeValue() method after I draw the card, but nothing is working for me.**/
System.out.println("Dealer draws: " + dealer);
do {
dealer = (d.draw());
System.out.println(" " + dealer);
}while (dealer.rank() <= 17);
Card mine = d.draw();
System.out.println("\t\t\t\t Player draws: "
+ mine);
mine = d.draw();
System.out.println("\t\t\t\t\t\t" + mine);
do{
String input = JOptionPane.showInputDialog
("Would you like a card? ");
if(input.equalsIgnoreCase("yes"))
     mine = d.draw();
System.out.println("\t\t\t\t\t\t" + mine);
     playerTotal++;
     else if(input.equalsIgnoreCase("no"))
System.out.println("\t\t\t\t Player stands");
     else
System.out.println("\t\tInvalid input.
Please try again.");
I don't know how to go about making and calling a method or class that will combine the total cards delt to the player and the total cards delt to the dealer. The rank() method only seems to give me the last cards drawn to compare with when I try to do the tests.**/
if ((dealer.rank() > mine.rank())
&& (dealer.rank() <= 21)
|| (mine.rank() > 21)
&& (dealer.rank() < 22)
|| ((dealer.rank() == 21)
&& (mine.rank() == 21))
|| ((mine.rank() > 21)
&& (dealer.rank() <= 21)))
System.out.println("Dealer wins");
wins++;
     else
System.out.println("I win!");
break;
} while (playerTotal <= 1);
String stop = JOptionPane.showInputDialog
("Would you like to play again? ");
if (stop.equalsIgnoreCase("no"))
break;
if (rounds == 5)
System.out.println("Player wins " +
(CardDeck.rounds - wins) + "rounds");
} while (rounds <= 5);
private Card[] deck;
private int cards;
public static int rounds = 1;
public int cardValue;
/**When I try to compile this nested class, I get an error message saying I need a brace here and at the end of the program. I don't know if any of this code would work because I've tried adding braces and still can't compile it.**/
class Hand()
static int r = 1;
public Hand() { CardDeck.rounds = r; }
public int getRounds() { return r++; }
final class Card
public static final int ACE = 1;
public static final int JACK = 11;
public static final int QUEEN = 12;
public static final int KING = 13;
public static final int CLUBS = 1;
public static final int DIAMONDS = 2;
public static final int HEARTS = 3;
public static final int SPADES = 4;
public Card(int v, int s)
value = v;
suit = s;
public int getValue() { return value; }
public int getSuit() { return suit; }
public int rank()
if (value == 1)
return 4 * 13 + suit;
else
return 4 * (value - 1) + suit;
/**This works, but I'm confused. How is this method called? Does it call itself?**/
public String toString()
String v;
String s;
if (value == ACE)
v = "Ace";
else if (value == JACK)
v = "Jack";
else if (value == QUEEN)
v = "Queen";
else if (value == KING)
v = "King";
else
v = String.valueOf(value);
if (suit == DIAMONDS)
s = "Diamonds";
else if (suit == HEARTS)
s = "Hearts";
else if (suit == SPADES)
s = "Spades";
else
s = "Clubs";
return v + " of " + s;
private int value; //Value is an integer, so how can a
private int suit; //string be assigned to an integer?
}

Thank you so much for offering to help me with this Jamie! When I tried to call change value using:
Card dealer = (d.changeValue());
I get an error message saying:
Incompatible types found: int
required: Card
I had my weekly class last night and the professor cleared up a few things for me, but I've not had time to make all of the necessary changes. I did find out how toString worked, so that's one question out of the way, and he gave us a lot of information for adding another class to generate random numbers.
Again, thank you so much. I really want to learn this but I'm feeling so stupid right now. Any help you can give me about the above error message would be appreciated.

Need Help With Shell Programming

Hi, I need some guidance as to how to approach my project.
I need to develop a shell to host an e-learning environment that can be accessed through the internet. The user, preferably, needs not to download anything to run/start the e-learning environment. This e-learning environment allows users/students to create a forum, create a chatroom, hand up projects, send mail, do surveys and tutorials online and these can be submitted to the teacher/marker and receive feedback and also view their grades and schedule. Eg, Blackboard http://www.blackboard.com/
The problem is is that there seems to be no shell programming by using java. I have found only shell programming using UNIX, korn and C. I read other posts in the forums here concerning shell programming and alot of the codes include the first 2 lines :
Runtime rt = Runtime.getRuntime();
String command = "your_shell_script_command";
try {
      Process process = rt.exec(command);
     from = new BufferedReader(new InputStreamReader(process.getInputStream()));
     to = new PrintWriter(process.getOutputStream(), true);
catch (IOException e) {         ...       }the above codes were taken from this post: http://forum.java.sun.com/thread.jsp?forum=57&thread=352231
Does it means that I need to use another language besides Java to program a shell and then run it together with my java program? If so, what language do I need to learn and what Java "component" do I need to use? and is it possible to run a shell in an applet, since the applet is viewable through a browser?
I really need some help on this problem as I don't have a clue to go about it at all. Thanks in advance.

er, actually the applet does not seem to load at all.
But from what you have written, yeah, I need to
process the user's input and in my case, his
selected/choosen options in a menu.
E.g, the user wants to create a forum, he/she chooses
the create forum option from the menu which is part of
the shell and something happens which allows the user
to customise the forum.
So, let me get this straight, I can create an applet
and run the shell on the applet and the user can view
this application without downloading anything? As YAT said...providing they have the java plugin...yes... if you keep it to java.applet.Applet (AWT) and not JApplet, you should even have more users able to run it without 'downloading' anything..
Now..to be clear... they ARE downloading your .class files, and running them within a JVM on their own local machine... But they will not need anything (assuming their browser supports the Java version you write in) else...

New to Photoshop (CS4Ext) and need help with basic loading of images to new folder.

Just purchased CS4Ext and installed it. It's not showing up on my desktop as a quick entry icon. I want to simply load images from a portable hard drive (USB) to a new folder in photoshop so I can review them and begin to select and separate out some of interest to manipulate and share or get ready to print. It 's the most basic help one can need butI'm jut not clear on the workflow steps . Would appreciate someone walking me through the steps .
Thanks much

drmjp2 wrote:
Just purchased CS4Ext and installed it. It's not showing up on my desktop as a quick entry icon.
Let's see… First of all, this is the Photoshop Macintosh forum. Installed applications never, ever show up on your desktop as a "quick entry" icon on a Mac. Are you on a Windows PC maybe?
drmjp2 wrote:
I want to simply load images from a portable hard drive (USB) to a new folder in photoshop so I can review them and begin to select and separate out some of interest to manipulate and share or get ready to print.
Just select them with your mouse in the Finder and drag-copy them into the new folder. Done.

Need help with basic "for" loops!

Here is my prompt for class:
Write a program that prompts the user to enter a sentence from the keyboard using JOptionPane.showInputDialog.
The program will print the characters back with the first letter of each word changed from lower case into upper case. If you have a capital letter in the original line and it is not the first letter of a word, then this letter should be switched from upper case to lower case. The only capital letters that should appear in the line must be the beginning letter of every word in the line. All other characters will remain the same.
I figured everything out except for one part. How do I make the first letter of each word change from lower case into uppercase? How do I switch a letter that is uppercase in the middle of a word to lowercase? Last but not least, how do I make sure that the only capital letters in the sentence are the first letter of each word?
I need to do this using for Loops, charAt(), and if/else statements because this is just an intro class. I just can't figure this last part out! Help please!

String words = ...;
StringBuilder builder = new StringBuilder();
for (int i = 0; i < words.length; i++) {
char c = words.charAt(i);
boolean isUpper = Character.?(look up the methods in java.lang.Character)
boolean isLetter = ? (there are actually 2 ways to do this. Hint: you can use <= and >= and && to solve this)
if (!isLetter) {
continue;
} else {
// check if this is the start of the word. How do you know that you are at the start of a word?
if (!isUpper && isStartOfTheWord) c = Character.toUpperCase(c); //Hint: there is a way you can do this with x + y
else if (isUpper) //make c lower case
builder.append(c);
return builder.toString();

Help with basic program

The program I am writing is supposed to ask the user to input a 4-digit Integer whose digits are not all the same, and then place the number in descending and ascending order, then subtract until the number 6174 is met.
I'm very new with java but I can't seem to get my if statement to loop back until the condition I want is met.
I know that a while statement will loop back, but when I tried that it just kept looping over and over again.
Any help and tips for later on in my project will be great.
import java.util.Scanner;
public class program2
    public static void main(String[] args)
      int      Number, D1, D2, D3, D4, Temp;
      Scanner Keyboard = new Scanner(System.in);
      boolean NoNumberYet;
      System.out.println("Please enter a 4-digit positive integer whose digits are all different: ");
      Number = Keyboard.nextInt();
      D1 = (Number/1000);
      D2 = (Number/100) %10;
      D3 = (Number/10) %10;
      D4 = Number %10;
      NoNumberYet = true;
      while(NoNumberYet)
        if (D1 == D2 && D2 == D3 && D3 == D4)
           NoNumberYet = false;
           System.out.println("The number you entered contains the same digits.");
           System.out.print("Please re-enter the number: ");
           Number = Keyboard.nextInt();
    }

On to a new question.
I need to subtract the rearranged descending number by the ascending arranged number.
I need to know how to place my rearranged digits in place of the original number and then subtract it.
Heres what I have so far:
import java.util.Scanner;
public class program2
    public static void main(String[] args)
      int      Number, d1, d2, d3, d4, temp;
      Scanner Keyboard = new Scanner(System.in);
      System.out.println("Please enter a 4-digit positive integer whose digits are all different: ");
      Number = Keyboard.nextInt();
      d1 = (Number/1000);
      d2 = (Number/100) %10;
      d3 = (Number/10) %10;
      d4 = Number %10;
      if (d1 == d2 && d2 == d3 && d3 == d4)
           System.out.println("The number you entered contains the same digits.");
           System.out.print("Please re-enter the number: ");
           Number = Keyboard.nextInt();
      if (d1 < d2)
         temp = d1;
         d1   = d2;
         d2   = temp;
      if (d2 < d3)
         temp = d2;
         d2   = d3;
         d3   = temp;
      if (d3 < d4)
         temp = d3;
         d3   = d4;
         d4   = temp;
      if (d1 < d2)
         temp = d1;
         d1   = d2;
         d2   = temp;
      if (d2 < d3)
         temp = d2;
         d2   = d3;
         d3   = temp;
      if (d1 < d2)
         temp = d1;
         d1   = d2;
         d2   = temp;
}Any help would be appreciated, also the output needs to appear on screen.
My guess is that I need to somehow drop d1, d2 ,d3, and d4 into a new variable, and then subtract from the reverse. I dont know how to drop the digits into a new number, or the original entered number.
Thanks.
Message was edited by:
Bmiller234

Need help with Java programming installation question

Sorry for my lack of knowledge about Java programming, but:....
A while back I thought I had updated my Java Runtime Environment programming. But I now apparently have two programs installed, perhaps through my not handling the installation properly. Those are:
J2SE Runtime Environment 5.0 update 5.0 (a 118MB file)
and:
Java 2 Runtime Environment, SE v 1.4.2_05 (a 108MB file)
Do I need both of these installed? If not, which should I uninstall?
Or, should I just leave it alone, and not worry about it?
Yeah, I don't have much in the way of technical knowledge...
Any help or advice would be appreciated. Thank you.
Bob VanHorst

Thanks for the feedback. I think I'll do just that. Once in a while I have a problem with Java not bringing up a webcam shot, but when that happens, it seems to be more website based than a general condition.

I need help with this program ( Calculating Pi using random numbers)

hi
please understand that I am not trying to ask anymore to do this hw for me. I am new to java and working on the assignment. below is the specification of this program:
Calculate PI using Random Numbers
In geometry the ratio of the circumference of a circle to its diameter is known as �. The value of � can be estimated from an infinite series of the form:
� / 4 = 1 - (1/3) + (1/5) - (1/7) + (1/9) - (1/11) + ...
There is another novel approach to calculate �. Imagine that you have a dart board that is 2 units square. It inscribes a circle of unit radius. The center of the circle coincides with the center of the square. Now imagine that you throw darts at that dart board randomly. Then the ratio of the number of darts that fall within the circle to the total number of darts thrown is the same as the ratio of the area of the circle to the area of the square dart board. The area of a circle with unit radius is just � square unit. The area of the dart board is 4 square units. The ratio of the area of the circle to the area of the square is � / 4.
To simuluate the throwing of darts we will use a random number generator. The Math class has a random() method that can be used. This method returns random numbers between 0.0 (inclusive) to 1.0 (exclusive). There is an even better random number generator that is provided the Random class. We will first create a Random object called randomGen. This random number generator needs a seed to get started. We will read the time from the System clock and use that as our seed.
Random randomGen = new Random ( System.currentTimeMillis() );
Imagine that the square dart board has a coordinate system attached to it. The upper right corner has coordinates ( 1.0, 1.0) and the lower left corner has coordinates ( -1.0, -1.0 ). It has sides that are 2 units long and its center (as well as the center of the inscribed circle) is at the origin.
A random point inside the dart board can be specified by its x and y coordinates. These values are generated using the random number generator. There is a method nextDouble() that will return a double between 0.0 (inclusive) and 1.0 (exclusive). But we need random numbers between -1.0 and +1.0. The way we achieve that is:
double xPos = (randomGen.nextDouble()) * 2 - 1.0;
double yPos = (randomGen.nextDouble()) * 2 - 1.0;
To determine if a point is inside the circle its distance from the center of the circle must be less than the radius of the circle. The distance of a point with coordinates ( xPos, yPos ) from the center is Math.sqrt ( xPos * xPos + yPos * yPos ). The radius of the circle is 1 unit.
The class that you will be writing will be called CalculatePI. It will have the following structure:
import java.util.*;
public class CalculatePI
public static boolean isInside ( double xPos, double yPos )
public static double computePI ( int numThrows )
public static void main ( String[] args )
In your method main() you want to experiment and see if the accuracy of PI increases with the number of throws on the dartboard. You will compare your result with the value given by Math.PI. The quantity Difference in the output is your calculated value of PI minus Math.PI. Use the following number of throws to run your experiment - 100, 1000, 10,000, and 100,000. You will call the method computePI() with these numbers as input parameters. Your output will be of the following form:
Computation of PI using Random Numbers
Number of throws = 100, Computed PI = ..., Difference = ...
Number of throws = 1000, Computed PI = ..., Difference = ...
Number of throws = 10000, Computed PI = ..., Difference = ...
Number of throws = 100000, Computed PI = ..., Difference = ...
* Difference = Computed PI - Math.PI
In the method computePI() you will simulate the throw of a dart by generating random numbers for the x and y coordinates. You will call the method isInside() to determine if the point is inside the circle or not. This you will do as many times as specified by the number of throws. You will keep a count of the number of times a dart landed inside the circle. That figure divided by the total number of throws is the ratio � / 4. The method computePI() will return the computed value of PI.
and below is what i have so far:
import java.util.*;
public class CalculatePI
public static boolean isInside ( double xPos, double yPos )
     double distance = Math.sqrt( xPos * xPos + yPos * yPos );
public static double computePI ( int numThrows )
    Random randomGen = new Random ( System.currentTimeMillis() );
    double xPos = (randomGen.nextDouble()) * 2 - 1.0;
    double yPos = (randomGen.nextDouble()) * 2 - 1.0;
    int hits = 0;
    int darts = 0;
    int i = 0;
    int areaSquare = 4 ;
    while (i <= numThrows)
        if (distance< 1)
            hits = hits + 1;
        if (distance <= areaSquare)
            darts = darts + 1;
        double PI = 4 * ( hits / darts );
        i = i+1;
public static void main ( String[] args )
    Scanner sc = new Scanner (System.in);
    System.out.print ("Enter number of throws:");
    int numThrows = sc.nextInt();
    double Difference = PI - Math.PI;
    System.out.println ("Number of throws = " + numThrows + ", Computed PI = " + PI + ", Difference = " + difference );
}when I tried to compile it says "cannot find variable 'distance' " in the while loop. but i thought i already declare that variable in the above method. Please give me some ideas to solve this problem and please check my program to see if there is any other mistakes.
Thanks a lot.

You've declared a local variable, distance, in the method isInside(). The scope of this variable is limited to the method in which it is declared. There is no declaration for distance in computePI() and that is why the compiler gives you an error.
I won't check your entire program but I did notice that isInside() is declared to be a boolean method but doesn't return anything, let alone a boolean value. In fact, it doesn't even compute a boolean value.

Need Help With Basics of SQL

Hey I'm trying to get a working understanding of some of the basics behind SQL, I've composed a few questions that I think may help me with this. Anyone that can help me with any of them will greatly help me thanks.
1. How to create synonym for tables?
2. How to describe the structure of tables?
3. How to list the contents of tables?
4. How to create a table named with the same structure as another table?
5. How to copy rows with less than a certain criteria in value (e.g. Price<$5.00) into another table?
6. How to change the data type to e.g. NUMBER(6)?
7. How to add a new column named with data type e.g. VARCHAR2(10)?
8. How to change a specific field within a table (e.g. For ORDER_NUMBER 12489, change the C_NUMBER to 315)?
9. How to delete a specific row from a table?
10. How to declare a column as the primary key of a table and call it e.g. PK_something?
11. How to show certain columns when another column is less than a certain criteria in value (e.g. Price<$5.00)?
12. How to show certain columns with another column having a certain item class e.g. HW or AP?
13. How to list certain columns when another column e.g. price is between two values?
14. How to list certain columns when another column e.g. price is negative?
15. How to use the IN operator to find certain columns (e.g. first and last name of customers who are serviced by a certain ID)
16. How to find certain columns when one of the columns begins with a particular letter (e.g. A)
18. How to list the contents of the a table sorted in ascending order of item class and, within each item class, sorted in descending order of e.g. price?
19. How to do a count of column in a table?
20. How to sum a column and make rename is something?
21. How to do a count of a column in a table (without repeats e.g. if a certain number repeats more than once than to only count it once)?
22. How to use a subquery to find certain fields in columns when the another column’s fields values are greater than e.g. its average price?

848290 wrote:
Hey I'm trying to get a working understanding of some of the basics behind SQL, I've composed a few questions that I think may help me with this. Anyone that can help me with any of them will greatly help me thanks.To use the terminology you have in those questions, you must already have a basic understanding of SQL, so you have exposed yourself as not being the author of such questions.
Please do not ask homework questions without having at least attempted to answer them yourself first and show where you're struggling.

URGENT!!! Need help with drawImage program.

Hi...,
This is my first time dealing with drawImage. This is my program:
public void init ()
img=getImage (getDocumentBase (), "knight.gif");
do
row=Integer.parseInt (JOptionPane.showInputDialog ("Enter starting row: "));
while (row<1 || row>8);
do
col=Integer.parseInt (JOptionPane.showInputDialog ("Enter starting col: "));
while (col<1 || col>8);
moves=1;
board=new int[9][9];
public void paint (Graphics g)
createBoard (g);
if (checkPos (col+1, row+1))
board[row][col]=moves;
g.drawImage (img, col*50, row*50, this);
g.drawString (Integer.toString(moves), ((col*50)+25), ((row*50)+25));
moves++;
makeMove ();
I just include these 2 mehtods because there is something wrong when I execute this. In the paint method, I only do the drawImage once, but I don't know why it draws twice when I execute it. And when I put the "g.drawImage" line in comment, it's doing ok.
I hope you guys understand me.
Please help me. Thx

Hi JeroenBoven,
Thanks for your help. But, this is what I put in the createBoard method.
private void createBoard (Graphics g)
          g.setColor (Color.black);
          for (int l=1; l<=9; l++)
               g.drawLine (50*l, 50, 50*l, 450);
               g.drawLine (50, 50*l, 450, 50*l);
From what I think, the createBoard only drawLines and make a 8 * 8 board.

Need help with basic program.....!

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