I must fill a 2d array randomly and then apply methods to the array. However i keep getting an out of bounds exception no matter what dimensions i use. I have a test and a class program.
import java.util.*;
import java.lang.Math;
import java.util.Arrays;
import java.util.Random;
class SummerStats {
Random rand = new Random();
[Code] .....
I need to make a string filled with naughts and crosses like this one : "xxx ooo xox". There are 3 groups separated with a space. how to fill the string randomly ?
View Replies View RelatedI need to write a program but I am having hard time filling an array of triangles...we are suppose to have 3 different classes..1 class of points..1 class of triangles and 1 main method which apply all those..here what I have been come up so far for the point class which I believe is good..
public class Point {
private float x;
private float y;
//Making x equal to the x coordinate and y equal to the y coordinate like on a graph
public Point(float xCoordinate, float yCoordinate) {
x = xCoordinate;
y = yCoordinate;
[Code] ....
Now here is my question how I am suppose in the main method fill an array of triangles for 100 triangles or less?
THE PROGRAM DOES NOT HAVE ERRORS. FILL THE 2D ARRAY WITHOUT DUPLICATES VALUES. AND DISPLAY IF THE ARRAY IS MAGIC SQUARE OR NOT.
View Replies View Relatedmy validAccounts array will not fill properly and has a null value in it.I added a print statement that prints the contents of the array and it is filling correctly but the very last value is null. I am supposed to be asking the user for a account number and password and it is not printing out correctly due to the fact that the array is not filled correctly.
import java.util.*;
import java.io.*;
public class ATM2 {
public static Scanner kbd;
public static final int MAXSIZE = 50002;
[code]....
My validAccounts array has a null value in it when i print it. How to do this.
I am NOT allowed to use bufferedReader or ArrayLists. This must be done with loops.
import java.util.*;
import java.io.*;
public class ATM2 {
public static Scanner kbd;
public static final int MAXSIZE = 50002;
public static void main(String[] args) {
kbd = new Scanner(System.in);
[Code] ....
I created and an Array of integers how can I get randomly get/pick the index of each array element.
View Replies View RelatedI am attempting to make a 5x5 bingo board. My array generates 75 numbers(15 per bingo letter) and displays them in a random order. What I am having trouble figuring out is how to fill the 5x5 grid with 25 numbers from my array. And yes, my code is probably much longer and much more redundant than it needs to be. Also, I think I'm using cells and grids terribly wrong (possibly the entire java language) but I'm not sure.
import java.util.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;
import java.awt.event.*;
import java.util.ArrayList;
import java.awt.GridLayout;
import javax.swing.JButton;
public class bingoboard extends JFrame
[code]...
i am trying to print out a randomly generated array, but i only get
[I@7852e922
i did some research and the "[" is for arrays, "I" is for the int and "@" is the hash. and the rest is some sort of hex. I need to override this in a way, but i can't seem to find out how.
this is my current code:
import java.util.Random;
public class Oppgave {
public static void main(String[] args){
int myint[] = fyll();
System.out.println(myint);
}
public static int[] fyll() {
[Code]...
Now I am trying to print the 4 string randomly from string array..where string contains no of words which are splitted from the file....
View Replies View RelatedI'm trying to build a monopoly like game, and atm I'm trying to find way how to build the Community and Chance chest cards. so far, my logic is
1-create an ArrayList of cards with a given order
2-for a given number of times(for loop) generate 2 random numbers ,which will be the parameters for Collection.swap().
3-swap.
here's the code for the shuffler Button
shuffler.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
for(int i=0;i<shuffeledMessages.length;i++){
int randoma=(int)(Math.random()*4);
int randomb=(int)(Math.random()*4);
Collections.swap(myMessages,randoma,randomb);
}
}
});
For now things seem to work pretty ok, but I'm wondering if this is a good and efficient way to shuffle a card chest especially in case of large number of cards. plus, I'm not sure what would be a good loop count for effective shuffling, in my case I used i<arraylist.size
I'm trying to generate a random word from the array that I have made including the words by making it corresponding with a randomly generated number. So for example, if the number generated is 0, then the word that the person has to guess would be "AUNT". How would I transfer the randomly generated number from one method into the array method to get the word the person has to guess?
Write a program called Word Guessing Game. Open the file FourLetterWords.txt and write the contents into an array of Strings (the file has 87 words in it). Then use a randomly generated number between 0 and 86 to select a word. The player will then try to guess the word selected by the game. The player is allowed 7 tries, if the player does not guess the word on the 7th try he/she losses. Display the letter of the word as they are guessed in the correct order, you will also display the incorrect letters. The game is over when:
- The player completes the word, or guesses the whole word correctly.
- The player does not guess the word in seven tries.
The player must also be allowed to terminate the game.
The game must have at least 5 classes:
- Main Class
- Class to return a random integer between 0 and 86.
- Class to return a populated array of 87, 4 letter words.
- Class to return a character that the player enters from the keyboard.
- Class to display both the correctly guessed letters and the incorrect letters.
My code (it is not complete, my attempt to do what I am trying to do is obviously not working.)
import java.util.Scanner;
public class WordGuessingGame {
public static void main(String[] args) {
final int NUMBER_OF_WORDS = 87;
RandomWordGenerator.random(NUMBER_OF_WORDS);
[code]...
Started learning about Array's I'm doing an exercise where you create a for loop that randomly assigns values to each element within the array, but where is my code going wrong?
import java.util.Scanner;
public class ArrayExamples{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
double exampleArray[] = new double[5];
System.out.print("Enter a Number: ");
int num1 = input.nextInt();
[Code] .....
I have an assignment for college that involves placing randomly chosen words from a text file into a 2-d array. I have nearly completed ithowever I am having difficulty with a list of string type.What I have done so far is below,
import java.util.Arrays;
import java.util.List;
import java.util.ArrayList;
import java.io.*;
import java.lang.Math;
[code]....
when I try to run an instance of the program(using BlueJ) I get an error saying there is a null pointer exception at line 35 which is wordsForGrid. add (puzzleWords.get(pos));
I am thinking that this is related to the fact that at this line in the loadWordsFromFile method List <String>words=new ArrayList<String>(); I could not create an empty list of string type, i.e List<String>words = new List<String>();
Is this correct? Or am I looking in the wrong place. The textfile I am using contains over 6000 words on a separate line for each if that makes any difference.
I want to create a simple app that takes a name from the console then compares the name to a small phone book,when the name matches another name it will return the associated phone number.
I have a small contacts class which has name and number fields,Then I have a phone book class which populates an array with 4 contact objects that I can compare the entered number against.
here is my contacts class
public class Contact
{
String name;
int number;
[Code].....
In the main method I am just trying to print out one of the fields for one contact to see if I can actually access it to compare it to the name entered.Its saying "MaryJones" cannot be resolved to a type.I'm guessing I cant create all that code in the constructor?
The experiments will slowly converge towards one big experiment: a simple game. I have just a little interest in games (perhaps I should have more), but making one - even a simple one - should be self rewarding.
However, now to the point.
* The experiment creates an array of rectangle objects.
* The rectangles are painted inside a Frame object at random x,y coords generated by a random number generator
* The rectangles are stationary.
* The rectangles are each assigned their own random colour.
* The array of rectangle objects is created inside the constructor of the class.
The actual code contains various other variables and methods which would distract from a quick analysis, so below is code which has the same logical structure which also fails (instead of array of rectangles, I have used arrays of integers).
import java.util.Random;
/**
* Experiment 14 - see if it works simply - (with integer arrays)
*/
public class TestingArrays {
// instance variables
int N = 10; // the size of the array - 10 elements
int[] a;
[Code]...
I am working in NetBeans and I am receiving numerous error messages with my code "not suitable constructor for lineItem.
import java.util.ArrayList;
public class Transaction {
private final ArrayList<LineItem> lineItems;
private int customerID;
private String customerName;
private String LineItem;
private int i;
[Code] .....
Specific Requirements for the Transaction Class :
1. The Transaction class should have a constructor with two parameters. The first is an integer containing the customer's ID and the second is a String containing the customer's name.
2. There should be a method to allow the addition of a line item to the transcript. The three parameters for the addLineItem method will be (1) the item name, (2) the quantity, and (3) the single item price.
3. There should be a method to allow the updating of a line item already in the transaction. Notice that updating an item means changing the quantity or price (or both). The parameters for the updateItem method are also (1) the item name, (2) the quantity, and (3) the single item price.
Notice that the updating of a specific line item requires a search through the ArrayList to find the desired item. Anytime a search is done, the possibility exists that the search will be unsuccessful. It is often difficult to decide what action should be taken when such an "exception" occurs. Since exception handling is not covered until later in this textbook, make some arbitrary decisions for this project. If the item to be updated is not found, take the simplest action possible and do nothing. Do not print an error message to the screen. Simply leave the transaction unchanged.
4. The transaction class needs a method called getTotalPrice to return the total price of the transaction.
5. There should also be a method to return information about a specific line item. It should return a single String object in the same format described for the LineItem class:
Colgate Toothpaste qty 2 @ $2.99 $5.98
Again, the possibility exists that the search for a specific line item will fail. In this instance, you should return a string containing a message similar to this:
Colgate Toothpaste not found.
6. The final method needed is a toString method. It should return the transaction information in a single String object. It should use the following format:
Customer ID : 12345
Customer Name : John Doe
Colgate Toothpaste qty 2 @ $2.99 $5.98
Bounty Paper Towels qty 1 @ $1.49 $1.49
Kleenex Tissue qty 1 @ $2.49 $2.49
Transaction Total $9.96
So I want to write a constructor that creates a new object with the data from the array values. I don't know where to start. It's the last method in the code:
public class Measurements {
private double[] values;
private double[] newArray;
private int n; //numberofvalues
private double[] ms;
public Measurements(int max) { //constructor
[code]....
Java Code:
import java.io.*;
import java.util.Scanner;
public class asciiFile {
int height;
int width;
Scanner input;
char[][] poop;
public asciiFile(File f) throws FileNotFoundException{ //constructor
[code]...
The constructor is supposed to take an ASCII file, take the numbers in the file, and populate a 2D array with the numbers in the file.
For some reason, the for loop I use to populate the array works outside of the constructor. When I put it in one of the methods, it runs normally. However, when I keep it in the constructor, I get the following error:
Exception in thread "main" java.lang.NullPointerException
at asciiFile.<init>(asciiFile.java:16)
at main.main(main.java:6)
I've a vertical-bar-delimited file where most elements contain text, some contain whitespace, and some are empty. Examples:
62RG|fe|Pencil Financial Group, LLC||doug@pencil.com|||85637889|Cross, Ben|bcross@godaddy.net|Bernard|Cross|Ben||315 One Tree Hill Terrace|Lafayette|LA
62RG|fe|Pencil Financial Group, LLC||tracy@pencil.com|||13658734|Dustin Cardwright|dcart@motorola.com|Dustin|Cartwright|||| |LA
which I parse and store with
String str_arry = innline.split( "|", 17);
lisst.add( new Contact( str_arry));
and my Contact class has the constructor
public Contact( String[] str_arry) {
for( int ii = 0 ; ii < str_arry.length ; ii++ ) {
if( str_arry[ii].matches("^s+$")) {
str_arry[ii] = null;
System.out.println("hit a null");
[Code]...
I expect the for-loop in the constructor to find any elements containing whitespace characters and set them to null for subsequent assignment.And when the code runs I do see some hit-statements pop up, so the detecting part is working.
But when I then process the list and access a Contact object and test fields for nulls I don't find any ie
if( aContactObj.getfFCity() == null) System.out.println("city is null");
never prints when it should.
What's the trick? Or is my approach wrong and if so what should it be?
We get a database and some DAO classes. We had to fill a ShowPanel with different shows being given in a theatre, and then when you choose from this you get several dates. Then when you click a date, the seatings appear in the SeatPanel. I got the first part with the shows and dates. But Im stuck at getting the seatings.We have a controller class which calls the shows+dates (this happens in one method). But i always get a nullpointerexception for the seatings. (this happens in a different method). I think i just don't know how to link the chosen show+date with the seatings.For the moment i have
public ArrayList<Seats> getSeating() throws SeatingException{
Show s = shows.getName();
ArrayList<Showdate> showdate = s.getDates();
ArrayList<Place> seating = new ArrayList<Place>();
try{
for (Showdate sd : showdate ){
[code]...
The given class PlaceDao has a static getInstance() method and an ArrayList<model.Place> getSeating(model.Showdate showdate) method.In the next stage i have to try and fill the panel with the seatings, but first i need to be able to call them.
I would like to make a small gift for my dad and i have a spreadsheet and i would like to make a small program that asks information and the puts it in the right column in the spreadsheet .For example i ask how many children do you have in your class and you answer 7 and that number goes into the spreadsheet.
View Replies View Related"which code is best for randomly generating integer 0 or 1". Haven't gotten my grade back yet but in reading these during the test I didn't think any of these would kick out both of those numbers, but there was no "none of the above" option on the test.This is exactly how it appeared on the test:
A) (int)Math.random() + 1
B) (int)(Math.random() + 0.2)
C) (int)Math.random()
D) (int)(Math.random() + 0.8)
E) (int)(Math.random() + 0.5)
I've tried all of them in the cs lab 100 times each and none of them generated both numbers. 'A' kicked out 1 every time. 'B,D and E' kicked out 0.2, 0.8 and 0.5 respectively each time, and 'C' kicked out 0. Did I just not run them enough times for the result to change or am I right in thinking there's a glitch on the test?
My random integer always seems to be zero.. I am at the ends of my wit.
package Exercises;
import java.util.Random;
import java.util.Scanner;
import javax.swing.JOptionPane;
/**
* Heads or tails?
* That is what this is.
*/
public class num14 {
[Code] ....
Attached File(s) : New Text Document.txt (2.59K)
I have to write an example program to fill boxes most efficiently with bags. All bags are the same size. The boxes come in Large, Medium and Small. Large boxes hold 20 bags. Medium boxes hold 10 bags. Small boxes hold 5 bags. I am getting input from JOptionPane input dialog box and then parsing that input to an integer.
I have to fill the large and medium boxes completely. I am not sure how to do this without an if statement. I can use one, but we have not covered it in class, so I am skeptical about using one to solve the problem. If I just divide the input number with integer division, I'm not going to get the remainder, right? So I'm thinking that I can mod my input number by 20 (the number of bags the user inputs) and then mod that number by 10 and then mod that number by 5, would that work?
Why this code is not working/my JTable won't updated after i click the button
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.ResultSet;
[code]....