Implementing Try / Catch With BinaryToDecimal Program
Apr 27, 2014
I've been assigned to write a program that will convert binary to decimal that uses the try/catch block. In the program that I have written, I was wondering if it is possible to write an addition catch statement that will present an error if any number other than a 0 or 1 is entered by the user. I have already done this in the binaryToDecimal method, but I am just messing around to see if it is, in fact, possible.
Java Code:
import java.io.IOException;
import java.util.Scanner;
public class BinaryToDecimal {
public static void main(String[] args){
Scanner input = new Scanner(System.in);
There is a method taken from a class with several try and catch blocks. If you think it is possible, add one more catch block to the code to catch all possible exceptions, otherwise say 'Not possible' with your reason.
I tried to write a program to implement a stack but it has a bug I am unable to solve.The bug is that whenever I choose an operation to perform, eg push, After performing the operation, the loop is executed once again and Invalid choice message appears, i.e. the default case. And then the loop again executes to choose further option. Here is my code
class Stack { private char[] stck; private int len; private int top;
I need to design, implement, and test a program to input and analyze a name. The program begins by retrieving a user input string from the keyboard. This string is intended to be the user's name. These are the errors we have to search analyze the user input for: No blanks between names firstName and lastName, Non-alphabetic characters in names, Less than two characters in first name, and Less than two characters in last name. Each of these errors must be thrown. All exceptions must be derived from a programmer-defined class called NameException. Each exception should use a detailed message to differentiate among the file types of errors.
This is the format of my NameException class, is the format itself correct? I will fill in the details of each exception I am just wondering if that is how I should set it up.
public class NameException extends Exception { private String firstName, lastName; public NoBlanksException(String firstName,String lastName) { } public NonAlphabeticalCharactersException(String firstName, String lastName) {
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I was told not to try and catch thrown errors in the main method, would I just create another method in the Driver class to take care of that then?
I wrote a program using switchcase.I used do while to show the menu to the user until the user decides to exit the menu.I used try catch to prevent ant exception and it worked properly.But i got one problem.When exception occurs,desired msg is printed but i am unable to display the menu to the user.So user wont be able to continue after an exception is caused.
public class ThrowException { public static void main (String[] args) { var x=prompt("Enter a number between 0 and 10:",""); try { if (x>10){ throw "Err1"; } else if (x<0){ throw "Err2"; } else if (isNaN(x)){ throw "Err3"; } } catch(er){
[code]...
It's telling me where catch(er) is: <identifier> expected..I've watched videos, but no one seems to encounter this error....am I missing a segment of code?
In the following piece of code Iam confused as to where the InputMismatchException in the catch block is thrown on the first place? Is the InputMismatchException thrown automatically with declaring to throw the exception?
import java.util.*;
public class InputMismatchExceptionDemo { public static void main(String[] args) { Scanner input = new Scanner(System.in); boolean continueInput = true;
Is it a best practice to return from try block or place return statement after try-catch when we intend to return a value from a method(* Catch block is being also used to rethrow the exception)??
So method invia call the method popolaScompiute, inside popolaScompiute there is an iteration through some id and for some id can occur an error; what i want is the getting the value of id in the first method invia, using the block try/catch. Is there a way to accomplish this?
Regarding return statements within methods. So I have a method containing try and catch block (as required) and much like when you have an if else statement... I noted you have to return an object for both the try and catch blocks. Now in my case my method should return a List object.
The way I have tried to overcome this:
- I've initialised a List object to null as an attribute of the class I'm working in. - Therefore in the catch block would just simply return the null List object, where as the try block would return the non-empty List (which is what I want). - I then just test to see if the List != null, when the method is invoked... and that is that.
However the method always seems to return null (when it shouldn't).
So I'm pretty sure this is correct, as it follows most examples I can find online, but I keep getting an error that my return variable cannot be resolved. The error is on the return conn; statement. It says conn cannot be resolved. If I place it above within the try block it allows it but then I receive an error saying the method getDBConnection must return type Connection.
I don't want to create this method. Basically I want to connect to the database in the main program, but I do want methods that can access the DB too. But however I place it, it doesn't let me touch any of the DB variables outside of the Try block.
So method invia call the method popolaScompiute, inside popolaScompiute there is an iteraction through some id and for some id can occur an error; what i want is the getting the value of id in the first method invia, using the block try/catch. Is there a way to accomplish this?
public class hello { /** * @param args */ public static void main(String[] args) { int s = new hello().h(); System.out.println(s); } public int h(){ try{ int g = 10/0;
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the output is 7. how the flow is working. i understand that there is a divide by zero exception after which the control goes to catch. what about the return statement in catch . why is it overridden by finally..........
I'm not even sure if I'm trying to place it in the correct area in the code. However I like to perform this prior to the receipt being displayed so if there a issue the user can correct this before the final receipt has been sent .......
I came across a code where the exceptions can be thrown from catch and finally block too. I never gave a thought on what scenarios that can be required. Some practical examples when/where it can be required to throw the exception from catch and finally blocks.
I want to use a try catch block, but I am not sure how to fix this problem:
int a;
try{ a = Integer.parseInt(A.getText()); } catch (Exception e){ Output1.setText("Error"); }
//do someting with a here
The purpose of the try-catch is to catch blank input.The problem with this is that underneath the try - catch I get an error saying that the variable might not have been initialized. I know why this happens. I know I could initialize the varaible before the try - catch, but there is no default or null I can set an int as. If I initialized it as 0, the blank input will no longer be catched.how to make this problem disappear?
Right now we are learning about arrays and using the try/catch. Code below, I am trying to just display information about buildings. The application is good but not with the try and catch statement. I'm trying to just display the message of "please enter a building number" when a user puts a letter instead of a number(InputMismatchException) and then the user would have to put in one of the numbers. But when it runs and i put in a letter, it reads the message, but it always outputs the first building information ...
package username; import java.util.InputMismatchException; import java.util.Scanner; //TallBuildings public class TallBuildings { //compare heights of buildings
I want to write classes with methods that perform JDBC operations that throw SQL exceptions. For many of the methods, I'd ideally like to be able to have them catch exceptions and just send them to a standard Logging system "IF" the code that calls the methods is not going to catch the same exception. However, I'd like the "option" to have code that calls these methods catch the same errors if I want to but not "Require" the calling routines to catch them.... so I don't want to declare the methods with a "throws" that would require all calling code to Try/catch.
For some background, the logic behind what I'm looking to do is that there will be lots of places where these classes and their methods may be used where the code is basically "throw away" scripting code where just having error logs generated is more than sufficient. However there are also places I want to use the same classes/methods that I would want to handle the exception differently. So, for at least half the places I want to use these methods, there's no good reason to require cluttering the calling code with Try/catch, but when I DO want to handle the exceptions, I'd like them to get passed up to the calling routine so I can handle them in a way that is appropriate for the calling routine. Does that make sense?
I guess I'm kind of looking for is the ability to "override" the catch of a called method "IF" I want to but to treat the method as though it doesn't throw any exception "IF" I don't want to override the called routines catch logic.
The requirement is to write a rectangle class and a test class, which include try-catch blocks and exception handling. Exceptions, involving try, catch, throw, throws, and finally commands,how to write a code about basic things, but in the test class, it gives me specific width and height so that i dont konw how to write a try-catch blocks an exception handling in this test class.There is my two classes, they are separated.
public class Rectangle { double width ; double height ; Rectangle(){ width = 1; height = 1;
I have created this ping pong game but having problem with ball and paddle collusion. After first collusion it gives score 1 but later it never touch the paddle.
Code:
import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.awt.geom.*; import java.util.Random.*; import javax.swing.ImageIcon; public class Ball extends JFrame implements ActionListener, KeyListener{ int xSpeed=0;
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I think something is wrong here:
public void actionPerformed(ActionEvent e){ y=y+xSpeed; repaint(); if(y> this.getWidth()){ y=25; score -=1; } if(blockRect.intersects(ballRect)){ y=40; score +=1; x =200; y = 300; }
If I put the highlighted text in try/catch block it is throwing NullPointerException , if I am using command line arguments then also it is showing the same exception.
java 7 feature (Multicatch and final rethrow ).. how to print user defined message in catch block with respect to multiple exceptions in single catch block...
Ex: }catch (IOException | SQLException ex) { System.out.println("Exception thrown"); /** * i want like this, if IOException is thrown then System.out.println("File not Found"); * if SQLException is thrown then System.out.println("DataBase Error"); */ }
what is the use of checked exception.I know unchecked exception or Runtime exception are thrown by jvm whenever programmer makes any mistake in logic and current thread is terminated.But checked Exception are checked at compile time so that compiler compels programmer to put risky methods in try catch clause. And this checked Exception are caused due to problem in IO operation or any such operation which the programmer can't control.Programmer can't do anything to avoid this checked exception but can catch this exception.
Now the question is Why compiler compels checked exception to be put in try catch clause but doesn't complain anything in case of Runtime Exception???
