I had to use scanner to receive input from the user for a formula and everything compiled and worked correctly except when I entered a double into the Scanner, it only accepts ints and gives me this error every time I enter a double:
java.util.InputMismatchException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at java.util.Scanner.nextDouble(Unknown Source)
at TestA1Q2.main(TestA1Q2.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)
I know that you usually get that error when the Scanner expects something else that is different from what you type and I have looked over my code time and time again and cannot find anything. I created a test program to see if it was just that problem and not something else in the code and I still got the same error but when I tried compiling and running it here browxy.com everything worked and I got the right answer for the formula. Here's the test I used:
import java.util.Scanner;
public class TestA1Q2 {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Enter a double");
double velocity = keyboard.nextDouble();
}
}
At this point I'm thinking it might be a problem with my install of DrJava and I've tried re-installing but nothing changed.
I have a Homework that's on Polymorphism and inheritance. The problem is of a triangle class. The super class is GeometricObject and the subclass Triangle. I have the parent and child classes compiling, now it's the test program.
The problem is the examples in the book don't show anything about prompting input for objects. The objects in the Triangle class are: side1, side2, and side3 and so I created objects in the test: Triangle sideOne = new Triangle(); . I've tried to compile but jGrasp doesn't like anything I do and the instructor in my class hasn't shown us examples yet. Can I prompt input for reference type and not just primitive type?
I have been asked to write a library program that will keep record of books and the year it was published. The program should ask the user how many rows he wants accept the string input from the user and display them in rows and columns. This is how i code it
package multidimension; import java.util.Scanner; public class bookrecords { public static void main(String[]args){ //declaring a scanner variable Scanner input =new Scanner(System.in);
I'm allowing the user to choose certain items to buy that is moved to an array.Now I'm trying to add those thing in the array use a different class. how I can call the array from my driver class to my checkout class that adds them together.
Code a Java method that accepts a String array and a String. The method should return true if the string can be found as an element of the array and false otherwise. Test your method by calling it from the main method which supplies its two parameters (no user input required). Use an array initialiser list to initialise the array you pass. Test thoroughly.
public class test { public static void main(String[] args) { Printhelloworld(); String[] verbs = {"go", "do", "some", "homework"}; printArrays(verbs);
while(fileScan.hasNextLine()) { String currentLine = fileScan.nextLine(); String[]dataSet = currentLine.split(" "); String zip = dataSet[7]; String phone = dataSet[8]; String donation = dataSet[9]; int ZIP = Integer.parseInt(zip); Double Donation = Double.parseDouble(donation);
As you can see I made the donation read as a double, my question is how do I get the donation total? I need to write the code to add up and get the total donations but cannot figure it out.
Just done a quick test to try and figure out the difference between floats and doubles.I made a quick program which outputs the result of 3.3 * 2 as both a float and a double.
I assumed since a float is the larger and more precise of the two data types that there would be more numbers after the decimal point, however this was not the case, it was in fact the double which had more numbers after the decimal point. Result was as follows:
Float: 29.699999 Double: 29.7
BTW for the above code I simply had a few text fields and a button with the following code:
Also, as these are limited to a certain amount of numbers im thinking there must be a more precise way for currency, if so what would I use for that? I suppose what im trying to figure out is what data type to use in different scenarios? When to use integer, float, double and long.
Write a Java method that returns the largest value of an array of doubles passed to the method as an argument.
Back into java wasn't sure how to do it for doubles did one in the main for integers and then added a method changed from int to double and now i'm lost as go why its not working.
package kickstarter9; public class Kickstarter9 { public static void main(String[] args){ double myList; double[] myList = {6.0, 4.1, 2.4, 6.8, 1.9, 9.4, 2.8, 4.6, 9.3}; // find the largest value in the list
This code will let a user type 10 double's, and return the smallest of those 10 double's. But I don't really understand what happens in de last for-loop.
package hsleiden.webcat.exercise06_09; import java.util.Scanner; public class Exercise06_09 { public static void main (String[] args){ double[] allNumbers = new double [10];
I've been noticing some of my programs have been a little buggy recently, and think it's down to confusion over doubles and positioning. Lets say I have a label called banner that I want to scroll across the screen. Now I need to know the label's width in order to position it, but the width depends on the amount of text, so i use this code:
double bannerWidth = banner.getWidth();
Which forces me into using a double if I want to be accurate.
But the problem is that I'm trying to use a condition that compares the label's horizontal position (currentX) to the left edge of the screen (LEFT_EDGE), minus the width of the label (bannerWidth). In other words when the label is off the screen, it should go back to its starting position.
I assume that means that any variables I use to track the label's position (in this case currentX), or constants that I use to check equality (LEFT_EDGE), have to be doubles as well?
My difficulty is that I iterate currentX. But currentX--; won't work because doubles don't iterate as I'd expect.
So casting becomes an option..... but if I cast to an integer I effectively lose width on the label. And that is magnified each loop, resulting in the label's starting position moving further and further to the left.
I'm attempting to format my doubles to two decimal places within my return statement. I have tried to use DecimalFormat but it gives me an error because my method needs to return a double and that results in a string being returned. I have also tried using the *100.00/100.00 method and that doesn't work when the number already ends in 0.
If I pass -150.00 it gives me -150.0 when I need two decimal places.
"Create a project called RainFall and a class nameD RainFall. Write a program that stores the total rainfall for each of 12 months into an array of doubles. The program should display total rainfall for the year, the average monthly rainfall, the month with the most rain and the month with the least rain. When outputting the month with the most and least rain, output the name of the month. This is what I have so far.
why does sevenPointsOrLess only work if I declare it as a String and use next() instead of nextInt()? Also why does it take part of the next line with it?
Here is the text I am trying to scan:
England,3,0,1,2,0 Samoa,1,0,3,0,1
Code:
lineScanner.useDelimiter(","); country = lineScanner.next(); Won = lineScanner.nextInt(); Drawn = lineScanner.nextInt(); Lost = lineScanner.nextInt(); fourOrMoreTries = lineScanner.nextInt(); sevenPointsOrLess = lineScanner.next();
Results:
country = "England" Won = "3" Drawn = "0" Lost = "2" fourOrMoreTries = "2" sevenPointsOrLess = "0 Samoa"
I'm trying to write a basic java program so that when I run it, I can store the names and codes of some of my school textbooks...I try the scanner statement to input the name of the book but an exception is thrown when I type the name of the book..I have attached the code for my program.
import java.util.Scanner; public class Books{ public static void main(String[] args) { Scanner s=new Scanner(System.in); System.out.print("Enter amount of products : "); int products= s.nextInt(); long [] code= new long[products]; String[] names = new String[products]; for (int x=1;x<(products+1);x++){ System.out.println("Enter IMEI number "+x); code[x] = s.nextLong(); System.out.println("Enter name "+x);
I created a variable for the scanner called serena. Serena variable is equal to what the user inputs. My if statement says that if the answer the user enters is not equal to the actual answer then it is to display "wrong". It is a basic math game I am working on. NetBeans is telling me that I cannot use the scanner in an if statement?
package pkgnew; import java.util.Scanner; public class New{ public static void main(String args[]){ Scanner serena = new Scanner(System.in); double fnum, snum, answer;
[Code] ....
Do I have to define Serena as whatever number the user inputs? If so, how?
Scanner sc = new Scanner(System.in); Question question = new Question(); Quiz quiz = new Quiz(); System.out.print("Enter the prompt: "); question.prompt = sc.nextLine();
[Code] .....
Here is the example run that I am trying to achieve:
* 1. Enter the prompt: What is the capital of the USA? * 2. Enter a possible answer: New York City, NY * 2. Is New York City, NY the correct answer (y/n)? n * 3. Enter a possible answer: Pittsburgh, PA * 3. Is Pittsburgh, PA the correct answer (y/n)? n * 4. Enter a possible answer: Washington, DC * 4. Is Washington, DC the correct answer (y/n)? y * 5. Enter a possible answer: Chicago, IL * 5. Is Chicago, IL the correct answer (y/n)? n
The problem is that my for loop runs through correctly the first time, but doesn't seem to react to me initializing my choices array after that. It ends up looking like this:
Enter the prompt: What is the capitol of the USA? Enter a possible answer: New York City, NY Is New York City, NY the correct answer (y/n)?n Enter a possible answer: Is the correct answer (y/n)?
I have a small bug in my program. The user is asked what person(s) information they want to access but lets say they want captain they must enter "captain" twice. I think it will make more sense to you with the code. I have searched all over to see what is causing the bug but still have found no resolution. I even tried making two different scanners but that didn't work either.
I know the while loop (line 16) I am using is causing the bug because it works fine without that but then I cannot validate the input.
package myproject; import java.util.Scanner; public class Enterprise { public static void main (String[]args){ String userInput;
My program is supposed to let me enter the following info for 3 employees: name, number of hours worked this week, and hourly pay rate. It lets me enter the name for the first employee, but for the second and third, it skips over the name and forces me to enter the number of hours worked and pay rate without a name. I have the code and the output posted below. First the program code:
Java Code:
import java.util.Scanner; public class SalaryCalc { public static void main(String[] args) { Scanner input = new Scanner(System.in); String name; double hours; double rate; double grossPay = 0; double overtime;
[code]...
Enter hours worked this week: mh_sh_highlight_all('java'); Notice I can only enter the name for the first employee (Bigfoot). If I wanted to enter "Nessie" for my second employee's name, it skips over the name prompt and prompts me for the hours worked instead.