What is an exception in java with an example javatpoint
What is an exception in java with an example javatpoint
I'm happy to help!
In Java, an exception is an event that occurs during the execution of a program that disrupts the normal flow of instructions. It's a mechanism to handle abnormal or unexpected situations that might arise while your code is running.
An example of an exception in Java is when you try to divide a number by zero, which is not possible in mathematics. In this case, Java will throw an ArithmeticException
.
Here's an example:
public class Main {
public static void main(String[] args) {
try {
int result = 10 / 0; // This line will throw an exception
System.out.println("The result is " + result);
} catch (ArithmeticException e) {
System.out.println("An error has occurred: " + e.getMessage());
}
}
}
In this example, when the program tries to execute the line int result = 10 / 0;
, it will throw an ArithmeticException
because you're trying to divide a number by zero. The try
block is where the potentially hazardous code is placed, and the catch
block is where you handle the exception.
Here's what happens when the program runs:
The program executes the lineint result = 10 / 0;
. Java realizes that you're trying to divide by zero, which is not possible. Java throws an ArithmeticException
, signaling that something went wrong. The program jumps out of the try
block and enters the catch
block. In the catch
block, you can handle the exception. You might want to print an error message or roll back some changes.
In this case, when the exception is caught, it will print: "An error has occurred: / by zero".
Remember that exceptions are used to handle abnormal situations that may arise during program execution. It's essential to handle them correctly to ensure your code remains robust and reliable.
I hope this example helps illustrate how exceptions work in Java!
What is an exception in Java give an example?
I'd be happy to help!
In Java, an exception is a runtime error that can occur when your program is running. It's like a surprise party popper that goes off in your code - you didn't expect it, but now it's happening!
There are two main types of exceptions: checked and unchecked.
Checked Exceptions
These are the exceptions that Java forces you to handle explicitly. This means you need to put your code inside a special block called a try
-catch
block. Here's an example:
try {
File myFile = new File("example.txt");
FileReader fileReader = new FileReader(myFile);
// ... do some reading ...
} catch (FileNotFoundException e) {
System.out.println("The file does not exist!");
}
In this code, we're trying to read a file. But what if the file doesn't exist? That's where FileNotFoundException
comes in - it's an exception that gets thrown when the file can't be found. We need to catch this exception with a catch
block and handle it nicely.
Unchecked Exceptions
These are exceptions that Java doesn't force you to handle explicitly. They're like little surprise gifts that you might not even know about until your program crashes!
Here's an example:
int[] myArray = {1, 2, 3};
System.out.println(myArray[5]);
In this code, we're trying to access the sixth element of an array (remember arrays start at 0!). But what if our array only has three elements? That's okay - Java will just crash and give us an ArrayIndexOutOfBoundsException
. We don't need to put this in a try
-catch
block because it's not something we can predict or handle.
Example Program
Let's say you're making a simple calculator program. You want users to be able to divide two numbers, but what if they try to divide by zero? That would cause an exception! Here's how you might handle that:
try {
double num1 = Double.parseDouble(input("Enter the first number: "));
double num2 = Double.parseDouble(input("Enter the second number: "));
double result = num1 / num2;
System.out.println("The result is " + result);
} catch (Exception e) {
System.out.println("Invalid operation! Try again.");
}
In this code, we're using a try
-catch
block to handle any exceptions that might occur. If the user tries to divide by zero, or if they enter something that's not a number, our program will catch the exception and print out an error message.
And that's it! Exceptions are like little surprises in your code - sometimes good, sometimes bad. But with try
-catch
blocks, you can make sure your program handles them nicely and keeps on running!