How To Declare ArrayList That Can Hold Int Variables
Mar 26, 2012Any way of How to declare an ArrayList that can hold int variables?
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Declare And Creates Integer Array That Can Hold 15 Integers
Nov 3, 2014The main Method
-Create a main method declares and creates an integer array called nums that can hold 15 integers.
-Use a for loop to fill that array with multiples of 3: 0, 3, 6, 9, etc.
-Then use similar for loop to print each value in the array on one line, with each value separated by a single space.
-Compile and run the program to see the result:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
As you write other methods, you'll also modify the main method to make calls to them. The printArray MethodWrite a method called printArray that accepts an integer array as a parameter. This method does not return a value, and must be declared as static so that the main method can call it. Instead of printing the array in the main method, move that loop into this method. Call the printArray method from the main method. Compile and run the program to verify it prints the sam result as before.Add a println statement so that after printing the array values on one line, it then moves to the following line.Finally, modify the loop in the printArray method so that, instead of using a traditional for loop, it instead uses a for-each loop. Compile and run the program again.
Part III: More Array Methods
The linearSearch Method In lecture we looked at a method that performed a binary search on a sorted array. A much simpler (though much less efficient) search is a linear search, that simply starts at the front of the array and looks at each element in turn until it finds it or reaches the end.Create a method called linearSearch that accepts an integer array and a single int value as parameters. The goal of the method is to find the second parameter (the target) in the array. The method should return a single int representing the index of the target value. This method should not print any output itself. In this method, use a traditional for loop to scan through the elements in the array. As soon as you find the target value, return the index of that value.
If you scan through the entire array without finding the target value, return a -1.Modify the main method to call the linearSearch method and print the results. Call it twice, searching for the value 18 (which it should find) and the value 10 (which it should not). Including the previous activity, the output of the main method should now look similar to this:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sumArray Method
The sumArray method should take an integer array as a parameter and return a single integer representing the sum of all values in that array.Use a for-each loop to access each value in the array and compute a running sum. After the loop, return the total.Call the method from the main method, producing the following augmented output:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sum of this array is 315
The addValue Method...The addValue method should accept an integer array and a single int as parameters. The purpose of the method is to add the second parameter to EACH value in the array. The addValue method does not return a value, but the elements inside the array will be modified. Call the addValue method from the main method, adding 100 to each element in the array. Then call the printArray method again to see the modified array values:0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
The index of 18 is 6
The index of 10 is -1
The sum of this array is 315 100 103 106 109 112 115 118 121 124 127 130 133 136 139 142
Test a Different Array..Finally, duplicate the content of the main method to perform similar tests on another array. Instead of filling it with multiples of 3, fill it with multiples of 4. And instead of using an array size of 15, use an array size of 20.Modify the values search for to include one that is in the array and one that isn't.Rerun the main method and carefully check the results.If you haven't been doing it all along (which you should), make sure the appropriate class and method documentation is included.When you're satisfied that all methods are working correctly, modify the main method to delete the second array tests.
How To Declare And Initialize Variables
Feb 14, 2015The problem is to figure out the number of cartons needed to box up the strawberries picked by the farmer and his wife. The farmer picks 8.4 lbs per hour and the wife pick 10.8 pounds per hour. They pick from 8 am until 4Pm (8 hours). You can put 20 pounds per box.I understand the word problem and how to declare and initialize variables. I'm just confused how to display the math into java to solve it.
View Replies View RelatedJGRASP Won't Allow To Declare Variables As Strings
Oct 10, 2014Java Code:
import java.util.Scanner;//Imports Scanner
public class operadoreslogicos//imports a public class {
public static void main (String [] args)//defines the state of a class {
Scanner input = new Scanner (System.in);//Inputs a scanner to read user
//keyboard
boolean cierto = true,// Declares variables as boolean and applies a value
[Code] .....
The word string is supposed to turn purple when I type it, but it just stays normal, so it doesn't declare hello and bye as variables.
Instantiation Efficiency - Declare Variables To Be Used In A Loop
Sep 6, 2014Where usually to instantiate and declare variables to be used in a loop. If you declare it outside to be used in the loop it will still be there when the loop is done, never to be used again and is just sitting there taking up memory. However, if you declare it inside the loop, you have the issue of it constantly creating space for said variable, but once it's out of scope it's gone. Is there any advantage performance wise to doing it either way?
View Replies View RelatedWrite A Program That Declare And Initialize Three Floating-point Variables
Oct 3, 2014Write a program OutCircle.java that declares and initializes three floating-point variables (r, x, y): the first variable represents the radius r of a circle centered at (0,0) and the second and third variables are the coordinates (x, y) of a point in the plane.Your program should print true if the point is outside the circle and false otherwise. Hint: A point is outside the circle when its distance to the center is greater than the radius.
View Replies View RelatedHow To Add Variables And Default Values To Arraylist
Mar 23, 2015I am facing difficulties in identifying the proper way to add the selected colors of cards into an arraylist. I am having an arraylist which is:
Java Code: private List<String> selectedCars = new ArrayList<String>(); mh_sh_highlight_all('java'); And one more for the carColors:
Java Code: private List<String> carColors = new ArrayList<String>(); mh_sh_highlight_all('java');
The selectedCards array will store the selected cars ['TOYOTA','MAZDA','NISSAN'] as per the selection from the user.For certain types, there is one default color which is 'Black', however for some of them, the user can select different colors.(ex. if selection is 'Toyota')
Java Code:
String carColor="";
String toyotaColor=""; // The value will be retrieved from the form once the user selected the color
if (selectedCars.contains("MAZDA"))
{
carColor="Black";
}
else if (selectedCars.contains("TOYOTA"))
{
carColor=toyotaColor;
[code]....
Fields Won't Hold Value Given Through Input?
Oct 18, 2014At the end of my main method, I want it to print out the input given that should have been stored in my sandwich class fields, but it didn't.
import java.util.*;
import java.lang.*;
public class SandwichBuilder {
public static void main(String[] args) {
Scanner inputDevice = new Scanner(System.in);
[Code] .....
Tic Tac Toe With GUI Using JButtons That Will Hold X And O Pictures
Jan 8, 2015I am in the process of creating a Tic Tac Toe game with a GUI using JButtons that will hold the X and O pictures. I have the picture appearing when i click it once but it jumbles up all the other buttons which is why i have to run the method resetAllButton() to set everything back. Once i click the x again it puts everything back how it is supposed to be and works normal. How can i get this to work in one click.
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TicTacToeGui extends JFrame implements ActionListener {
[Code] .....
How To Hold And Print Distinct Numbers
Sep 29, 2014I am able to get the integer in the array printed but I am lost on how to hold and print the distinct numbers.
This program will read in 10 numbers from the user via the console. It will display on the console only the distinct numbers, i.e. if a number appears multiple times in the input it is displayed only once.
Here is a sample test run:
Enter an integer: 2
Enter an integer: 6
Enter an integer: 1
Enter an integer: 8
Enter an integer: 6
Enter an integer: 1
Enter an integer: 2
Enter an integer: 4
Enter an integer: 7
Enter an integer: 5
The number of distinct values is 7
2 6 1 8 4 7 5
How To Make XML - Game To Hold High Scores Of Three Different Levels
May 22, 2015I am a beginning programmer and was learning how to make an XML. It was for a simple game and only needs to hold the highscores of three different levels. Here is what I coded:
try {
OutputStream fout= new FileOutputStream("highScores.xml");
OutputStream bout= new BufferedOutputStream(fout);
OutputStreamWriter out = new OutputStreamWriter(bout, "8859_1");
[code]....
My issue is that I run this code every time I create the program and the scores are reset to 0. How can I make a small change so that I only run this block of code and create the XML the first time the program is run?
Write TreeMap That Can Hold Maximum Of 20 Colors And Minimum Of 8?
Dec 11, 2014I am trying to write a TreeMap that can hold a max of 20 colors and a minimum of 8. I have a while loop using pollLastEntry to limit the max but I can't figure out how to set the minimum. The hex number is the map's key and the color name is the value. I tried to use entrySet() and iterator to just double the size of the map but map can't have multiple keys with the same value. It also seems that to set a minimum would require some kind of further input(which I'm trying to avoid) of colors and their hex numbers.
//Method to hard code the colors into the map
public TreeMap<String, String> cm() {
//Color Map <Hex number, Color name>
//Uses a TreeMap to keep all the colors organized by key
TreeMap<String, String> cMap = new TreeMap<String, String>();
cMap.put("FFFF00", " Yellow");
[code]....
How To Create A Box To Hold Text Below Google Maps Within Android
Feb 19, 2014At this point I know how to utilize Google Maps within Android but it always seems to take up the full window, there is an image below which shows what I'm attempting to accomplish (having a box below the Google maps where I can store text i.e. "Hello World"
How do I add box below Google Maps, so to store text i.e. "Hello World"
Code so far:
ActivityMain:
Java Code:
public class MainActivity extends Activity {
private GoogleMap googleMap;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
[Code] .....
Image:
Save Class With Arrays So As To Reload Them Again And Hold Onto List Of Objects Within Those ArrayLists
Dec 7, 2014I have a class with static ArrayLists to hold objects such as Members,Players etc.I want to save the class with the arrays so as to reload them again and hold onto the list of objects within those ArrayLists.
The ArrayClass
import java.io.Serializable;
import java.util.ArrayList;
public class ArrayClass implements Serializable {
[code]....
The arrays within the ArrayClass are empty when i reload the application.I cant tell if the arrays are being properly saved or is it in the reloading from file???
Can Database Storage And Queries Replace All Collections And Arrays (which Basically Hold Data)
Jan 10, 2014My friends and me are trying to make online Test taking system. We got a very basic doubt.
We have developed classes and relationship between classes for example : Online Test Taking system will have admin and student class. And Admin will have list of students.. etc.
But question troubled me was: if we use database to store all data for example student details then I can perform all sorts of operations writing sql query and store result in some other database then what is the need of "ArrayList<Student> field in Admin".??
Question is: We can put everything in database and manipulate using database(sql) functions to manipulate it.Then what is the need of Arraylist of anything which is just used to store object details for example student details....??
Declare Counter With Value Outside For Loop
Mar 29, 2015Is it possible to declare a counter with a value outside of a for loop?
I have a counter that will end prematurely in a while loop during various iterations and I want to pick it back up in a catch all for loop at the end
Let's say I have a while loop
while(something) {
total++
}
then after I have a for loop that I want to start at total but would rather do that then make a new counter variable.
for(total;total < 20;total++)
Is something like this possible or is this a horrible thing to want anyways?
Declare And Concatenate Various Strings
May 27, 2015Write a program that declares and concatenates various strings. Declare strings for your first name, middle initial and last name, along with one for your address, city, state and zip. Make an additional string called firstLine, which will be a concatenation of first name, space, middle initial, period, space, and last name. Assign each of these strings a value, and then print the information in the following format:
First Line (First name Middle initial (period) Last name)
Address
City, State
Zip
For example:
John Q. Public
1234 Any Street
Cleveland, Ohio
44101
Now reassign the strings in the same program (Do not create a separately compiled program!) and repeat the printout for different information. When you are finished, your program will print out two groups as above.
The information should be placed into the seven separate strings, then a first line should be formed by concatenating first name, space, middle initial, period, space, and last name. The city and state line should be formed by printing city followed by a comma, a space, then the state (NOT by concatenation). This is so you can see different ways of making lines."
And this is what I have so far:
JTable - Declare 2D Array
Jun 5, 2014I have a jtable which i want to put an array into... and Really don't know how.. I dont want to use array list mainly because it looks way to complicated so there must be some other way using defaultablemodel but i dont know how..
So here's my code: just a snippet which includes the testing of the jtable
String[] columns = {"col1", "col2", "col3", "col4", "col5", "col6"};
//declare 2d array
String[] [] data = {{"1", "2", "3", "4", "5", "6"}};
jt = new JTable (data, columns);
jt.setPreferredScrollableViewportSize (new Dimension (50, 80));
//set initial selectibility to false
jt.setFocusable (false);
jt.setRowSelectionAllowed (false);
JScrollPane tableContainer = new JScrollPane (jt);
frame.getContentPane ().add (tableContainer);
How To Declare Array In Java
Apr 16, 20151.How to declare array in java?
2.How to push elements in it in key-value value pair in java?
For example-
This is the way i do it in javascript..
I want to do like this in java..
var my_array;
for(var i = 0; i<5; i++)
{
my_array.push({x: i, y:0});
}
where,push is builtin method in javascript.
Declare Two Dimensional Array In Java?
Oct 28, 2014I want to declare a 2 dimensional array in java which has 3 column and unlimited number of rows, i want to give a special name to each column . The type of first column is string second one is int and the last one is string
Column1_name
Column2_name
Column3_name
String value
Int value
String value
.
.
.
.
.
.
Possible To Declare Two Data Input Stream?
Aug 3, 2014I mean i need to access to two txt file at the same time so i did this in method:
DataInputStream din= new DataInputStream(FileInputStream("vip.txt"));
DataInputStream din2= new DataInputStream(FileInputStream("corporate.txt"));
But there are errors when i compile and they pointing to these two lines.
Declare String Inside Of Loop - Use It Outside
Apr 26, 2015I'm trying to code a little text RPG. I've made a little "personality test", with 4 questions (answers a b c), where every letter stands for a type of personality. The analysis of the result is simple counting of the answers, if you have 3 answers a (4 questions), then a has won. If 2 on a, and 2 on b, a simple Random method shows weather result a or b.
Now... the test should give you a "partner" (imagine the pokemon game with 3 different starter pokemon). I have now 3 string variables, like 3 different partners. They are all declared somewhere outside, but i only need one later.
Like...the test is completed, you have your partner and how can i make now that the program is just showing me my partner? Like...when i type " System.out.println(partner); " (outside of the test loop! ) that i only get the one i got through the test?
I was trying to declare in every loop the partner String with every result. But outside the loop java isn't recognising that String, bcs...ofc...it was declared for the loop. So i had in every if or else if clause a " String partner = anwsA;" and answB and answC, thats why i cant declare them outside.
Short: i need a partner String variable that could have 3 possible results... i jut need one
I'm using Eclipse Luna 4.4
Declare Array And Populate It With Log Formula
Feb 10, 2014Still trying to get a handle on arrays! So, I declare an array to be a 46x1 and I am trying to populate it with a Log formula that I am using but I keep getting an ArrayIndexOutofBoundsException.
Code :
private double[][] LNValues = new double[46][1];
//Calculating y=LN(E-k) and Initializing the Array
for(int x=0; x<LNValues.length; x++)
{
double i = Math.log(eValues[x][1] - kValue);
if(i > 0)
[Code] ....
Declare A Class That Can Be Used To Represent A Quadrilateral
Jul 16, 20142. Declare a class called Quadrilateral that can be used to represent a quadrilateral. What instance variables are required? This class should include the following methods:
• Accessor and mutator methods. Notice that negative and zero lengths should not be accepted.
• A method called isParallelogram that returns a Boolean value indicating if the quadrilateral is a parallelogram.
• A method called isRectangle that indicates if the quadrilateral is a rectangle. This method should invoke the method isParallelogram and return a Boolean value.
• A method called isSquare that returns the Boolean value “true” if the quadrilateral is a square. This method should invoke the method isRectangle and return a Boolean value. URL...
import java.awt.Point;
public class Quadrilateral{
private Point p1, p2, p3, p4;
public Quadrilateral (Point p1, Point p2, Point p3, Point p4) {
this.p1 = p1;
this.p2 = p2;
this.p3 = p3;
this.p4 = p4;
}
}
that is all i got, my professor has never mentioned on anything about quadrilateral,and i have 0 knowledge about this.
Can Declare A Class Inside Interface?
May 8, 2013I have a doubt regarding to java.
Can we declare a class inside an interface?
Ans :yes
But what will be the situation?
I am not getting why it is required...........
Make Program That Declare Largest And Smallest Out Of Three Numbers?
Jan 13, 2015how can i make a program that declare the largest and smallest out of three numbers??
/*
* To change this license header, choose License Headers in Project Properties.
int a;
int b;
int c;
[Code]....