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?
@MappedSuperclass public abstract class BssStandardEntityLaravel extends BssStandardEntity implements InterfacciaBssStandardEntity, Cloneable{ private static final long serialVersionUID = 1L; @Column(name = "created_at", nullable=true) @Temporal(TemporalType.TIMESTAMP) protected Date created_at = new Date();
[Code] ....
When i try to read some data with a JPA controller, this error is raised:
Persistent class "com.bss.libbssabstract.database.entity.BssStandardEntityLaravel" has no table in the database, but the operation requires it. Please check the specification of the MetaData for this class. org.datanucleus.store.rdbms.exceptions.NoTableManagedException: Persistent class "com.bss.libbssabstract.database.entity.BssStandardEntityLaravel" has no table in the database, but the operation requires it. Please check the specification of the MetaData for this class. at org.datanucleus.store.rdbms.RDBMSStoreManager.getDatastoreClass(RDBMSStoreManager.java:702)
[Code] ....
It requires BssStandardEntityLaravel table like a normal entity. I used the same entity package in other applications and it works perfectly. Why this error is raised?
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?
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 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?!?
value1 = text1.getText(); value2 = text2.getText(); Connect c = new Connect(value1,value2); if(c.check()== true) { Menu start = new Menu(c.getID()); dispose();
[code].....
I get an error "unreported exception java.SQLException; must be caught or declared to be thrown" how can i solve this I have taken a few basic classes but never got to exceptions.
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.
import java.lang.*; class InvalidValueException extends IllegalArgumentException {} class InvalidKeyException extends IllegalArgumentException {} class BaseClass { void foo() throws IllegalArgumentException { throw new IllegalArgumentException();
[Code] .....
Which one of the following options correctly describes the behavior of this program? And the answer is (definitely) --> The program will print : InvalidKeyException exception, but when i saw the explanation, it tells
It is not necessary to provide an Exception thrown by a method when the method is overriding a method defined with an exception (using the throws clause).
I don't know, but i think it will compiled because the Exception that is thrown by the foo method in DeriDeri class is inherited from unchecked exception.. so it is not necessary to declare throws statement on its method.. and if the exception was checked exception the answer must be different right?
imagine I build this this device that takes in impulses... 0 and 1..but I need an interface with buttons to decide when to throw a 0 or a 1...would java be a good language to control this?I'm having difficulty to make this path... interface to circuit...
Dice are used in many games. One die can be thrown to randomly show a value from 1 through 6.
Design a Die class that can hold an integer data field for a value (from1 to 6).
Include a constructor that randomly assigns a value to a die object. Appendix D contains information on generating randomnumbers. To fully understand the process, you must learn more about Java classes and methods. However, for now, you can copy the following statement to generate a random number between 1 and 6 and assign it to a variable. Using this statement assumes you have assigned appropriate values to the static constants.
Also include a method in the class to return a die's value. Save the class as
Die.java.
Write an application that randomly "throws" two dice and displays their values. After you read the chapter Making Decisions, you will be able to have the game determine the higher die. For now, just observe how the values change as you execute the program multiple times. Save the application as TwoDice.java.
I got one task from my manager, regarding browser back button, refresh button. He asks me the web application has to work like Banks site... means if I refresh or click on Back button(Browser's) then it has to throw the user out of session, I checked lot in internet. But I found like only disabling back button of disabling F5 keys like that. But he’s not accepting that.
How to approach for this? Can we throw the user out of session when he clicks on browser back button or refresh button. I think its possible . But i don't know how to implement.
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.
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).
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);
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;
[Code] .....
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.
