import java.util.*;
public class CalculatorProjectVincent {
public static void main(String[] args) {
System.out.println("Welcome to this incredibly uneeded and redundant calculator program!");
breaker();
Scanner kb = new Scanner(System.in);
System.out.print("Enter an expression or EXIT to end the program. > ");
[Code] ....
When I run the program and input "v 100", it gives me the following:
----jGRASP exec: java CalculatorProjectVincent
Welcome to this incredibly uneeded and redundant calculator program!
- - - - - - - - - -
Enter an expression or EXIT to end the program. > v 100
Exception in thread "main" java.util.InputMismatchException
at java.util.Scanner.throwFor(Scanner.java:909)
at java.util.Scanner.next(Scanner.java:1530)
I am trying to read contents from a file and display them to the user. However, when I enter the file into the program I get the following error: "exception in thread 'main' java.util.MismatchException. What am i doing wrong?
import java.util.Scanner; import java.io.*; public class Project1{ public static void main(String[] args) throws FileNotFoundException { double balance; double item1Price;
I have written the following code to calculate tax payments based on income and filing status :
import java.util.Scanner; public class computeTax { public static void main(String[] args) { Scanner input = new Scanner(System.in); // prompt for filing status System.out.println("enter '0' for single filer,");
[Code] ....
The while loop initiated on line 21 is there so that in case the wrong input is given at the prompt given in line 24, the program outputs "please type the right answer" with the command on line 254 before looping back to line 24 and prompting the user to enter his status number. The program works as long as the input at line 28 is an integer. Not surprisingly if the erroneous input here is not an integer, the program outputs the following error message :
Exception in thread "main" java.util.InputMismatchException at java.util.Scanner.throwFor(Scanner.java:909) at java.util.Scanner.next(Scanner.java:1530) at java.util.Scanner.nextInt(Scanner.java:2160) at java.util.Scanner.nextInt(Scanner.java:2119) at computeTax.main(computeTax.java:28
To try to solve this I used the Try / Catch technique with the following version of the code :
import java.util.Scanner; public class computeTax { public static void main(String[] args) { Scanner input = new Scanner(System.in); // prompt for filing status System.out.println("enter '0' for single filer,");
I am trying my code which catches exception when mismatch variable is inputed as i read it with Scanner. It seems right for me but whenever i run it, it keeps leaking memory or something like that
Code :
import java.util.*; public class Exercise10_1 { static Scanner scanner = new Scanner(System.in); public static void main(String[] args) { boolean exception; do
I'm attempting to create a program that employs a method to count the number of 7s a user puts as an input into the program. I'm just getting started, but I'm getting an error when I try to implement a main method that says "Illegal start of expression"
What adjustments could I make to eliminate this error message?
// Add a main method here. public static void main(String[] args) { //Error occurs here public static int countSevens(int n) { // 0. Clean-up. Get rid of any minus signs as that is not a digit. n = Math.abs(n);
I am currently working on a small java programm. I use netbeans for it. And obviously I am new to java.
Basically its a calculator that change the input value into another value: like 10 € into whatever $ and same with Inch and Centimeters.
Therefore I need a second jDialog Form where i can change the factors for the calculator and start the calculator again.
Here is my problem: I can open the second Dialog but if I want to change the factor it doesn't change the value in the variable and the second calculator frame is with the old factors. It seems the double variable isn't working globally
I am stuck on one of the projects: Area Calculator
I am able to code an area calc that works, but am unsure how to move all the input/output to main like the project wants. here is a piece of my code so far:
I have the same thing for rectangle, square, and circle (of course with the correct formulas) and the program works perfect, but the assignment is still wrong until I can move the input/output to main. what do I do?
I am trying to learn how to use file input/output in addition to exception handling... The problem is my textbook wrote this chapter for a version of Java that hasn't come out yet, so everything I do "according to the textbook" doesn't work. any feedback on correcting these exception errors because I am not sure what is causing them or how to fix them.
I was able to have it display the name of the book in the Book.txt file, but when I added the second part if the file doesn't exist, that's when the errors came up and it wouldn't compile.
import java.io.*; import java.util.*; public class DisplayBook { public static void main(String[] args) { try { File book = new File("Book.txt"); FileInputStream in = new FileInputStream(book);
[Code]...
These are the compilation error messages I am receiving: (I have managed to get it down from 7 errors to just 4, but now I'm stuck)
DisplayBook.java:15: error: unreported exception IOException; must be caught or declared to be thrown while ((letter = in.read()) != -1) //if file exists, displays book title ^ DisplayBook.java:24: error: unreported exception FileNotFoundException; must be caught or declared to be thrown
I'm developing an application to track the status of a production flow-line and have hit a bit of a snag. When attempting to read saved data I run into this:
Exception in thread "main" java.lang.ClassCastException: flowline.End_Of_File cannot be cast to flowline.Operation at flowline.Station.checkLoadPreviousStationStatus(Station.java:91) at flowline.Station.main(Station.java:212) Java Result: 1
I've been reading up on different methods to saving and retrieving data and have decided ObjectInputStream would be the best option.
The save method works fine, I opted to use a EndOfFile class to determine when I've reached the end of the input stream. The problem is, when my loop encounters this object, it doesn't terminate the loop.
public void checkLoadPreviousStationStatus() throws FileNotFoundException, IOException, ClassNotFoundException, EOFException, TempArrayOutOfBoundsException{ Object loadOpn = null; End_Of_File eof = new End_Of_File(); File f = new File(fileName);
[Code] .....
The Operation cast is a cast to the objects my LinkedList contains. The highlighted line is where the exception occurs.
I know I can calculate the sum of squares as such:
// SumSquares.java: calculate the sum of two squares class SumSquares { static int sumSquares(int a, int B)/>/> { int asquare; int bsquare;
[Code] .....
But how can I modify the code so that it inputs a list of integer values in the range of -100 to 100 from the keyboard and computes the sum of the squares input values. And how would I go about using exception handling to ensure that the input values are in range and are legal integers.
I'm trying to make a puzzle that gets the user input and moves the rows either to the left or right, the columns move either up or down depending on what the user wants. The problem I'm getting is a type mismatch for my RL method which moves the rows to the left.
import java.util.*; import java.io.*; public class Numbrosia { static int [][] board = new int [5][5]; public static void main(String[]args){ Scanner scan = null; try{
My program is user input 20 char and the program will print the most common. So I use another int arr which count the number appears in the original array. i know its not so Effective but I don't know why it run but it stop in the middle. I got this code :
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 20 at Ex2.common(Ex2.java:39) at Ex2.main(Ex2.java:23)
import java.util.Scanner; class Ex2 { public static void main(String[] arg) { Scanner reader = new Scanner (System.in); char[] arr=new char[20]; System.out.println("Please enter 20 chars:"); for (int i=0;i<20;i++)
I've got a nasty nullpointer that I have tried to resolve to no avail as of yet. The program should prompt for a listings.txt file and take its info and write to a report file. Here's the stacktrace:
run:
Input file: listings Exception in thread "main" java.lang.NullPointerException at java.io.Writer.<init>(Writer.java:88) at java.io.PrintWriter.<init>(PrintWriter.java:113) at java.io.PrintWriter.<init>(PrintWriter.java:100) at kettask2b.PropertyListingsReport.main(PropertyListingsReport.java:34) Java Result: 1
Some adjustments that I have attempted are:
BufferedWriter pwfo = null; for (int i = 0; i < args.length; i++) { String string = args[i]; pwfo = null;
I was giving a quick skim to some tutorials on the internet where I have found the exception that is handled is also declared in the throws clause of the method wrapping the try-catch block. For a code representation consider the following:
public void methodName() throws IOException { try { ... } catch (IOException ex) { .... TODO handle exception }
Right, so I got this program. It takes input from the user and assigns it to fields on an object. But, it's meant to check the users input. If the user enters bad input, it's supposed to throw this exception. For each of these exceptions, theres a class specifically for it.
public class PayrollDemo { public static void main(String[] args) { Payroll pr = new Payroll ("Test Name", 234); System.out.println("Current Employee Information. "); System.out.println("Name: " + pr.getName()); System.out.println("ID: " + pr.getID()); System.out.println("Hourly Pay Rate: " + pr.getHourlyPayRate());
[Code] ....
And this is the exception class.
public class InvalidNameException extends Exception { /** No-arg constructor */ public InvalidNameException() { super("Invalid name"); } }
PayrollDemo.java:43: error: cannot find symbol InvalidNameException.InvalidNameException(); ^ symbol: method InvalidNameException() location: class InvalidNameException 1 error
It's just meant to tell the user that they entered an invalid value, which would mean if they entered an empty string instead of a name.
The program i am working on is to take string from the user which should be a phone number then it will return true or false based upon the method that checks to see if it meets the criteria of a certain format if does not it will return false otherwise return true. I am working on a if/else structure that will print this number is valid if it meets the criteria of the method i previously mentioned or return the number is not valid if it is false. the logic of the expression i put in the parentheses of the if/else statement. This is what i have so far:
if(){ System.out.println("The phone number is valid"); } else { System.out.println("This isn't a valid phone number"); }
Do i need to compare it based upon the method that checks if it is true?
I am working on a program to evaluate an expression without brackets using stacks. I am getting the following error :
3+1*2+4 -2.0
Exception in thread "main" java.util.EmptyStackException at java.util.Stack.peek(Stack.java:102) at java.util.Stack.pop(Stack.java:84) at assignment2.Evaluate.main(Evaluate.java:42)
I imported the Stack from java.util.Stack
package assignment2; import java.util.Scanner; import java.util.Stack; public class Evaluate { public static void main(String[] args) { Stack<String> ops = new Stack<String>();
[Code] ....
What is causing this error? Does it look like the program should function as intended?
So everything in my program is working EXCEPT when it comes to calculating the result. I am supposed to evaluate the expression using postorder traversal to return the answer. I am honestly not sure how I would get the postorder traversal to return the answer to the expression since the only thing we really went over was how it re-ordered the expression so that it would end in the postorder/postfix order. Anyways, currently the way that I have the public int evaluate(Node node)method set up is giving me a result of 0, which obviously is not correct.
Here's the section that I'm having issues with:
public int evaluate(Node node){ if(node.isLeaf()){ return Integer.parseInt(node.value); } int result = 0; int left = evaluate(node.left); int right = evaluate(node.right);
I am currently enrolled in my first Java class. I have taken C# in the past so I've messed with some regular expressions, but I am having trouble finding a good website for Java. Is the syntax the same?I want to create a regular expression to only allow the following characters: c C f F [and any 1-3 digit number].
I am getting the error "Line 54, illegal start of expression". Line 54 is where my "for" starts. It was running ok earlier, now I can't get this error to go away?
