I have this very simple application just to test console input:
import java.util.ArrayList;
import java.util.Scanner;
public class WriteTester {
[Code]....
When I let it run, only every third entry is put into the array list and I have to hit "enter" three times for the "break" in line 21 to trigger. I cannot find out why.
We were suppose to make a program for an assignment and the prof provided some codes to start of. What does this basically mean? How do i access the string arrays from consolelist?
class ConsoleInfo {
private String conTitle;
private double conPrice;
private int conQty;
private String conPic;
private static String empPassword;
ConsoleInfo(String title, double price, int qty,String pic)
[Code]...
How can i convert this linked list code to a read from input.txt
The first line in the input file will give the elements to initialize the linked list with. Consecutive lines will provide operation instructions.
Your code should read one line at a time. After reading each line, it should perform the corresponding operation and print the linked-list on the console.
If an operation is not possible, it should print "N/A".
Sample input file. Please note, the comments (// ...) are given for explanation, the input file will not have them:
4, 5, 6, 3// First line. This will provide the initial values for the linked list : 4->5->6->3
1, 9// Add a 9 at the front of the linked-list. After this operation the linked-list should be: 9->4->5->6->3
2, 1// Add a 1 at the end of the linked-list. After this operation the linked-list should be: 9->4->5->6->3->1
3, // Delete the first node in the linked-list. After this operation the linked-list should be: 4->5->6->3->1
4, // Delete the last node in the linked-list. After this operation the linked-list should be: 4->5->6->3
5, 11// Delete the node with the value 11 in it. Since this is not possible, it should print "N/A"
5, 6// Delete the node with the value 6 in it. After this operation the linked-list should be: 4->5->3
Sample output to the console:
4->5->6->3
9->4->5->6->3
9->4->5->6->3->1
4->5->6->3->1
4->5->6->3
N/A
4->5->3
My Code:
LinkedList.Java
class linkedList
{
protected Node start;
protected Node end ;
public int size ;
[Code] .....
I want to input character data from the console without using the BufferedReader class. I tried using the Scanner class but the compiler shows an error. This is what I tried:
sc.nextCharacter();
sc.nextcharacter();
sc.nextChar();
Sc.nextchar();
Is there any way I can input character data without using the BufferedReader class?
I am having a great deal of frustration trying to use the scanner to get user input from the eclipse console. Here is what I am trying to do.
Print a menu for the user with options, take that (1) char input and run it into a switch statement for processing. I have that done and it is working fine.
If the user chooses to enter strings for storage, They are instructed to enter their string and press enter to complete that string entry. Then enter the next string and press enter, etc.
So I have a While loop for this. Get the scanner input, store it in the LinkedList, get the next scanner input, etc. I get the scanner string and store it in a Linked list. That works fine. The user is instructed to simply enter a blank string to end the entry procedure, like just press Enter on the new line without typing a new string.
The problem is the scanner doesn't seem to return anything for me to Test to close this procedure. How do I TRAP the fact that the user just pressed enter so I can end my procedure? I have tried next() and nextLine() and reset(), etc. And I am getting knowhere.
I am trying to make a program in which first I am entering number of charachters and then in nextline their is exactly that number of characters should be enter after than program should stop taking input from console..this is I have try so far
private static ArrayList<String> chars;
static String inputdata;
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
chars=new ArrayList<String>();
[code]....
this is my code...in my code i cant give input form my console...it takes input but it doesn't save in a target file..My code is :-
package filetester;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;
[code]....
I am currently tackling homework for a small I/O-program with console input.Right now, only the part when you enter "E" or "e" on the console is implemented and the issue I am trying to tackle is described in the comment starting at line 38:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Vector;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.InvocationTargetException;
import java.util.Scanner;
[code]....
I'm having an issue, I have a scanner (Scan.nextLine();) that scans the console for input to fetch the string "word". Then I want to fetch a character using Scan.findInLine(word).charAt(number);. The problem is that the console requires me to write 2 lines in order for the program to move on. I only want the program to scan for a word, and then move on with what it has instead of requiring 2 inputs.
View Replies View RelatedUse the sort method of the arrays class to sort the values in the array, and print the median value(the 50th value) on the console followed by a blank line. Then, test this enhancement. Print the 9th value of the array on the console and every 9th value after that. Then, test this enhancement.
import java.util.Arrays;
public class ArrayTestApp
{
public static void main(String[] args) {
double [] arrayTest = new double[99];
//adding random number to each element in the array
for(int i=0; i<arrayTest.length; i++)
arrayTest[i] = 100.0*Math.random();
[Code] ....
OUTPUT
run:
The average is: 49.842845462514944
The median is: 49.68753724038633
The 9th value is: 2.599530043466969
The 9th value is: 11.486193141397095
The 9th value is: 20.14206270200648
[Code] ....
I'm writing a command line application of a calculator in Java. I need to be able to (as per program requirements) split the array of strings (6+3) into an array of strings? How would that be done? I know you can use the split method, but I am not really sure how that wold work to perform math with them?
On a side note: for this application, how could you make the program accept a variety of different lengths of strings to perform math with them?
Write a program to maintain a list of the high scores obtained in a game. The program should first ask the user how many scores they want to maintain and then repeatedly accept new scores from the user and should add the score to the list of high scores (in the appropriate position) if it is higher than any of the existing high scores. You must include the following functions:
-initialiseHighScores () which sets all high scores to zero.
-printHighScores() which prints the high scores in the format: “The high scores are 345, 300, 234”, for all exisiting high scores in the list (remember that sometimes it won’t be full).
-higherThan() which takes the high scores and a new score and returns whether the passed score is higher than any of those in the high score list.
-insertScore() which takes the current high score list and a new score and updates it by inserting the new score at the appropriate position in the list
I am working on a problem where i have to create a 2d array with given input of the dimensions (odd number) of array, along with a number within the array and to then print out all of the numbers surrounding that number.
Anyway, i am working on simply making the spiral, which should look like the one below.
n = 3
7 8 9
6 1 2
5 4 3
where the 1 always starts in the center with the 2 going to the right, 3 down, then left etc. etc. I was able to create the code by starting on the outer edges rather than the center and working my way to the middle, however my code always starts from the top left and goes around to the center where it needs to start from the top right. I am having trouble altering my code to meet this criteria. This is what i have thus far.
import java.io.*;
public class Spiral
{
public static void main(String args[])throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter the number of elements : ");
int n=Integer.parseInt(br.readLine());
[Code] .....
I am passing input from the user to a method that will initialize an array of the data (scores in this case). The method is filling the entire array with the last input value.
array initializer method
Java Code:
public static float[] inputAllScores(float validScore) {
float[] diverScores = new float[7];
for (int i = 0; i < diverScores.length; i++) {
diverScores[i] = validScore;
}
return diverScores;
} mh_sh_highlight_all('java');
[Code] .....
This program contains a superclass and a subclass that will gather the following information from the user:
name, address, phone number, and customer number.
Everything works fine except that I have to create a boolean method in this program that is required to determine based on user input whether they want to be added to a mailing list.
I cannot get this method to work with main, each time it is called it will always return the value but main will constantly read the last statement (else, where it will read "not wanting to be added to the mailing list).
The only way I can get this part of the program to work is by adding an equals method in main that ignores the case, but I am required to write a boolean method so this is not allowed.
Superclass:
public class Person
{
private String name;
private String address;
private String phoneNum;
public Person(String pName, String add, String number)
{
name = pName;
address = add;
[Code] ...
How do you format an arraylist?
Mine looks like this:
[<?xml version="1.0" encoding="UTF-8" standalone="no"?> <DefEnv id="Dev">, <Envt id="Test">, , <DB id="DM">,
But I want it to look like: I'd prefer if the '[' , '<>' and ',' were not on them also but I'm not too bothered about that bit.
[<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<DefEnv id="Dev">,
<Envt id="Test">, ,
<DB id="DM">, ]
I am creating a hangman game and I want to read in a list of words from a text file, but after the user inputs the name of the text file. I get 'Exception in thread "main" java.lang.NullPointerException'.
Here is the code, where I think the problems lie.
public void runModel(){
ArrayList<String> pirateWordsList = new ArrayList<String>();
System.out.println("What is the name of the file you would like to load? (The file included is called piratewords.txt'");
Scanner in=new Scanner(System.in);
String file=in.next();
load(file);
[Code] ....
The full error message is this:
Exception in thread "main" java.lang.NullPointerException
at uk.ac.aber.dcs.pirate_hangman.Model.load(Model.jav a:108)
at uk.ac.aber.dcs.pirate_hangman.Model.runModel(Model .java:45)
at uk.ac.aber.dcs.pirate_hangman.Main.main(Main.java: 6)
I have 3 classes Pet, Cat and Dog classes. Cat and Dog classes are childs of Pet class.
Each pet has the properties of
private String myName;
private int myX;
private int myY;
private int mySpeed;
private int myAge;
I have an array list which creates 100 dogs. How can I print out the dogs with the two highest age values?
Im trying to create a program in which I read line by line the contents of a text file, and then report each letter along with its frequency. I was wondering how to read through the lines and process it so that my program knows to increase by a number each time a letter appears in my text file. For example, if A appears in my file 5 times, B 3 times, and C 0 times I want to eventually print out
A -- 5
B-- 3
C-- 0
My first thought was to do this using array lists but is there any way I could do this without using one?
method called []getLetterGrades but the only hint My professor told me was that I needed to declare another array list for this method and he wouldnt tell me anything else so bummer. But I don't understand why if what we are returning is a char. It would make sense to return an array list of char to get letter grade. Which is what i did but since the function is a char, the array list character wont work as a return.Primarily i would like to know the type that is needed. I just want an explanation for an array list in this method and how it would serve in this method.
import java.io.File;
import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.Scanner;
[code]....
Directions: public static void initialize(ArrayList names, ArrayList sores)
You should write a function that sorts both array lists, based on the values in the scores array list. This is one of the more conceptually challenging parts of the assignment. You want to sort the scores array list, and simultaneously alter the names array list so that the names continue to line up with their respective scores by index. In the example data above, when the score 9900 moves to the first element of the scores array list, the name "Kim" should also be moved to the top of the names array list. The function should have the following signature:
I'm having trouble figuring out how to sort the lists.
import java.util.ArrayList;
import java.util.Scanner;
public class Assignment5
{
/**
*/
public static void main(String[]args) {
intializeArrays();
[Code] ....
I had to write a program that prompts the cashier to enter all prices and names, adds them to two arrays lists, calls the method that I implemented, and displays the result and use 0 as the sentinel value. I am having difficulty coming up with a for loop in the method, I believe I have the condition right but I am having trouble with the statements. I now know that String does not have the get property, but I have only done examples with integers and I am not very good with for loops and wouldn't know how to fix it.
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
ArrayList<Double> sales = new ArrayList<Double>();
ArrayList<String> names = new ArrayList<String>();
System.out.print("Enter Number of Customers");
double salesAmount;
System.out.print("Enter Sales for First Customers");
salesAmount = in.nextDouble();
while(salesAmount != 0)
[code]....
I am stuck on this exercise and I don't know what exactly is wrong. I think it's something with the .remove and the for each loop, but I am not sure.
public class seven {
public static void main(String[] args) {
ArrayList<String> list = new ArrayList<String>();
list.add("aaa");
list.add("brr");
list.add("unni");
[Code] ....
This is what i get
Exception in thread "main" java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
at java.util.ArrayList$Itr.next(Unknown Source)
at seven.removeDuplicates(seven.java:24)
at seven.main(seven.java:18)
Here I have an enum class
public enum Money{
ONE_PENNY(1),
TWO_PENCE(2),
FIVE_PENCE(5),
TEN_PENCE(10),
TWENTY_PENCE(20),
FIFTY_PENCE(50),
ONE_POUND(100),
TWO_POUNDS(200);
private int coin;
Money(int c) {
coin = c;
}
int showCoin() {
return coin;
}
and for a test class, I need an array list with a couple of coins in it (i.e. ONE_POUND, TWO_POUNDS) and a loop that adds together the values of the coins in the list and prints the result. How can I do this?
Im making a simple code to add an array to a List (the code im referring to is <String> )
import java.util.*;
public class L5_ArrayListProgram {
public static void main(String[] args){
String[] things = {"lasers","ghouls", "food", "dark"};
List<String>list1 = new ArrayList<String>();
for(String x: things)
list1.add(x);
My simple question is - what are the <String> ...<String> for? I understand it makes the list1 variable a string, but why is it made like this? do we usualy use <String> when we need to make a variable a String?
is there a way, to convert a List of Integers to Array of ints (not integer). Something like List<Integer> to int []?
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