I'm writing a program that accepts three doubles from the user, and performs calculations on them. I want to be able to handle input mismatch exceptions on each individually (i.e., if the user enters a double for the first, then a letter for the second, I'd like to be able to keep the value entered for the first, and only require that the user try again with the second, then the third, etc.)... I tried putting each input instance into its own try/catch blocks, but it always goes back to #1 when an invalid input is entered. Right now, I have all three in one try/catch:
i am currently making a game in java and currently i am working on the basic mechanics. most of it is working fine but i cannot seem to make it so when the user presses and movment key and space to fire a bullet the bullet fires in the direction they are moving. here is the code i have for movement.
public void keyPressed(KeyEvent e) { // TODO Auto-generated method stub int bulletx = Player.x + 100; int bullety = Player.y + 20; int key = e.getKeyCode(); if( key == e.VK_W){ p.moveUp(); } if(key == e.VK_S){ p.moveDown();
I need to generate a league table in Java based on results provided in the shape of user input. I have the 6 teams in an array. I need to ask the user how many wins, draws, losses each team has had.
for (String element : teams) { System.out.println( "Please enter the number of wins, draws and losses for " + element); int[] wins = new int [6]; int[] draws = new int [6]; int[] losses = new int [6]; }
How do I pull 3 separate values from the user and then store each value in a separate element of each array? so if one team wins 3, draws 2 and loses 1 - I need to put 3 into the wins array, 2 into the draws array and 1 into the losses array? I then need to total all this in a table.
The first line is the number of test cases and the second line is the corresponding values for the test cases. Java code for taking multiple inputs in the single line separated by a space.
I would like to ask you how can i execute the next code without errors.
I am trying to execute a jar (myFile.jar) file multiple times with different inputs from another jar file. More simple i have game with many players and i create a Round Robin scheduling for the tournament, i need to execute all the mach's of a round together.
When i run the next code it execute on the first game with the first players multiple times.
Java Code:
public class RunJARFile { //10 player //5 game per round public static void main(String[] args) throws IOException { for (int Tour = 0; Tour < 9 ; Tour++) { for (int Game = 0; Game < 5; Game++) {
I am just learning how to throw exceptions, and I'm stuck on the last part,
Here is where I created the exception that receives a string consisting of ID and wage.
public class EmployeeException extends Exception { public EmployeeException(String Employee) { super(Employee); } }
Here is where I created the Employee class with the two fields. I also believe I am throwing the exception if the hourly wage is < $6 or > $50.
public class Employee { int idNum; double hourlyWage; public void Employee(int empID, double empWage) throws EmployeeException { idNum = empID; hourlyWage = empWage;
[Code]...
Now, I need to write an application with three employees and display a message when an employee is successfully created or not. This is what I have so far... I'm trying to get it to work with one employee, and then I can easily go back and add two more.
import javax.swing.*; public class ThrowEmployee { public static void main (String[] args) { try { Employee one = new Employee(542, 15.20); }
[Code
The current compile error that I'm receiving is: ThrowEmployee.java:12: error: constructor Employee in class Employee cannot be applied to given types;
Employee one = new Employee(542, 15.20); ^ required: no arguments found: int,double reason: actual and formal argument lists differ in length 1 error
I have public void Employee(int empID, double empWage) in my Employee class, so why is it saying that no arguments are required? Not sure if I'm missing a step with throwing exceptions, because this error has always been a simple fix when I've come across it in the past?!?
In my EJB modules, to prevent that any JPA exception is ever thrown, I check the condition that would cause the exception beforehand. For example, the exception javax.persistence.EntityExistsException is never thrown because, before persisting the entity, I check if such primary key already exists in the DB. Is it the right way to do this?
Another approach is too allow the JPA exceptions to be thrown and catch them in a try-catch block, and then throw my custom exception from the "catch" block. However it requires to call EntityManager.flush () at the end of the "try" block. Otherwise the exception throw could be deferred and never be caught by my block.
There are times that my methods need to report the caller about many kinds of errors, represented as checked exceptions. This makes my methods look like very convoluted. It happens mostly when I work with stateless EJBs and databases. Sometimes I end throwing even 8 different exceptions! Are they too many?
Many of them inherit from common exceptions, so I've been tempted to throw the parent classes. But I've quickly discarded that option because I've read that it's a bad practice, since a method may throw only a subset of the children of that parent class, not all.
Finally, I've studied these possibilities:
1. Throwing the parent class (mentioned above). 2. Throwing a common exception with an error ID or code as message. 3. Throwing a common exception with an enum as member, as if it were an ID or code (safer than the #2).
All them show the same defect that the #1. However it's more a conceptual problem than a technical one, because my callers always use the same mechanism to treat every "specialization" of the same exception, without worrying about if the method really can return it or not.
I'm wondering about the use of exceptions to handle errors that might occur during file I/O when the I/O is done by a method implementing an interface's method. The idea is for the interface to provide a uniform way for application code to read (and write, though I'm not addressing that in this post) a document from a file, given a File object that specifies the on-disk location of the document. The "document" can be an instance of any class the application programmer wants it to be, provided that it can be created from a file stored on disk. Here's the interface definition:
public interface DocumentRamrod<T> { public T openDocumentFile(File file) throws FileNotFoundException; }
A simple implementation, when T is a class that just holds a String, might look like this (Please overlook the fact that there is no call to the BufferedReader's close method, as it's not needed for this example.):
public class MyRamrod implements DocumentRamrod<OneLineOfText> { public OneLineOfText openDocumentFile(File file) throws FileNotFoundException { return new OneLineOfText(new BufferedReader(new FileReader(file)).readLine()); } }
But, that one line where the file is read (Line 5) might generate an IOException.To cope with it, I could add a try-catch to the implementation like this:
public class MyRamrod implements DocumentRamrod<OneLineOfText> { public OneLineOfText openDocumentFile(File file) throws FileNotFoundException { try { return new OneLineOfText(new BufferedReader(new FileReader(file)).readLine()); } catch (IOException ex) { Logger.getLogger(MyRamrod.class.getName()).log(Level.SEVERE, null, ex); } } }
Or, I could add that to the list of exceptions defined for the method in the interface, like this:
public interface DocumentRamrod<T> { public T openDocumentFile(File file) throws FileNotFoundException, IOException }
But that's where I'm getting nervous, as it makes me realize that, with an infinite number of possible implementations of openDocumentFile, I can't predict what all the exceptions thrown might be.should I have openDocumentFile simply throw Exception, and let the application programmer sort out which one(s) might actually be thrown, should I keep listing them as it become clear which ones are likely to be thrown, or should I not have openDocumentFile throw any exceptions and let the application programmer deal with it in the implementation of openDocumentFile (with try-catch blocks, etc.)? In Good Old C, I'd have passed back a null to indicate some general failure, with the various callers up the call-stack having to either deal with it or pass that back themselves (until some routine up the stack finally did deal with it), but that seems like an approach the whole exception mechanism was designed to avoid.
I'm thinking the right choice is to have openDocumentFile throw Exception, and let the application programmers decide which subclasses of Exception they really want to deal with. But I have learned to be humble about the things I think, where Java is concerned,
I am having some difficulties grasping the concept of throwing your own exceptions. How do I get this to repeatedly ask the user to enter a valid value for hours. Also i am having difficulties in the method with using the throw new InvalidHrExcep("That value is invalid"); i cannot get this to work.
public class exceptionProgram { static Scanner console = new Scanner(System.in); public static void main(String[] args) throws InvalidHrExcep { int day=0; int month = 0; int year=0; int hours=0; int minutes=0; int seconds=0;
class A { final Object b; public A(C c) { try { b = c.someMethodThatMayThrowSomeException(); } catch (SomeException e) { b = null; // This line results in compiler error: "variable b might already have been assigned" } } // take away b=null line and you get "variable b might not have been initialized" on this line }
Why? How could 'b' be assigned if the exception was thrown?
currently we can able to monitor all calls given to this class but whenever any exception thrown in this class hierarchy we are not able to track it on exceptions.jsp of JAMON
I am designing/coding a blackjack GUI program and I'm trying to add function to my JButtons. Problem is, I now have 2 NullPointerExceptions.
public class GameConsole { Player user; Player dealer; Deck playingDeck; ValidateInput validate = new ValidateInput();
[Code] .....
I am trying to do. I am getting the following exception/stack trace at line 14 in userTurn()
Exception in thread "main" java.lang.NullPointerException at blackjackControls.GameConsole.userTurn(GameConsole.java:163) at blackjackControls.GameConsole.gamePlay(GameConsole.java:87) at blackjackControls.Main.main(Main.java:7)
and then the program continues and after I click the button I get :
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at blackjackControls.GameConsole.userTurn(GameConsole.java:163) at blackjackControls.ResultPanel$1.actionPerformed(ResultPanel.java:34) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028) //and then about 30 more "at" lines
Why am I getting these exceptions and how do I fix it?
I am having some serious difficulty getting my project off the ground. I have the following code:
FileInputStream file = new FileInputStream(new File("src/retestchecker/test_sheet.xlsx")); //Get the workbook instance for XLS file XSSFWorkbook workbook = new XSSFWorkbook(file); //Get first sheet from the workbook XSSFSheet sheet = workbook.getSheetAt(0); Row row = sheet.getRow(0); Cell x = row.getCell(3); System.out.println(x);
Everything is properly imported, etc etc.. But I am getting this error and I am not sure what it means:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/xmlbeans/XmlException at retestchecker.RetestChecker.main(RetestChecker.java:23) Caused by: java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlException at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
[Code] .....
Java Result: 1
I am using Netbeans and the latest version of Apache POI that was released May 11, 2015.
The line 23 that the error refers to is this line:
I'm trying to stress test JavaFX and I'm on Window 8.1 using 1.8.0_20-b26. I have an application that has many objects on the scene with animation timers and overall it purposefully runs very slow. I have listeners on the root AnchorPane for touch input and if I generate many touch point events after a few minutes I get "Too many touch points reported" exceptions (posted below) and the app of course no longer responds to touch input. Is it possible to catch the exception and then reset the scene touch input so it goes back to normal without restarting the application? If it lost any current touch input that's fine.
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: Too many touch points reported at javafx.scene.Scene$ScenePeerListener.touchEventNext(Scene.java:2686) at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleNextTouchEvent$346(GlassViewEventHandler.java:1090)
I have i am trying to implement tooltip through javascript, like when we click on an image link tooltip should be displayed and it should have close button/ close image to close that tooltip.like the same way i will have multiple images on page, when ever i click on the images all tooltips should be displayed on the page when ever i want to close that then only it should close through close button on tooltip.can we do it through java script or will go for jquery.
I'm very new to Java, and I am creating a program that takes multiple user input to create one face. I have a class for the eyes, nose, lips, and headshape. For some reason, my program is not drawing the graphics. ***for question purposes, I have only included my head shape class and my test class****
my "test" class:
import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; public class FaceTest { public static void main(String[] args) { String head = JOptionPane.showInputDialog("Would you like a circle, square, rectangle shaped head?: ");
I want to work on a project in which I have a GUI where I can choose certain variables from drop down menus. I want to use these variables to modify a few configuration files. I have looked upon internet for a few methods which can be used for the same. However, I am not sure about the method I should use. The files I want to modify consist of 10 -15 lines.
I have a LoginScreen class and one other class in my project. I want use user inputs (Username And Password) on other class if users details is true. I am stcuk at this point because when user attempt to Login connection is succesfully and other frame is coming to screen but i can reach user details anymore. Let me explain with codes;
LoginScreen class
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package deneme3; import java.sql.Connection;
[code]....
You can see Button Action in MainProgramWindow " System.out.println( ??? );" How i can retrieve users inputs from this class ?
I have made a simple form, it consists of 3 text box's textbox1, textbox2 and textbox3 as well as 1 button button1. What I want to be able to do is put numbers into textbox 1 and 2 and then show the multiplication of these numbers in textbox 3 when the button is pressed and I was wondering what is the standard way of reading these numbers from the text box and allowing us to do the conversion obviously in the textbox its a string and we need to convert to an int or double or whatever to be able to perform calculations on them then convert it back into a string to display in text box 3?
