class Main {
public static void main(String[] args) {
try {
// code that generate exception
int divideByZero = 5 / 0;
System.out.println("Rest of code in try block");
}
catch (ArithmeticException e) {
System.out.println("ArithmeticException => " + e.getMessage());
}
}
}1) Separating normal code from exception handling code to avoid abnormal
termination of program.
2) Categorizing in to different types of Exceptions so that rather than
handling all exceptions with Exception root class we can handle with specific
exceptions. It is recommended to handle exceptions with specific Exception
instead of handling with Exception root class.
3) Call stack mechanism : If a method throws an exception and it is not handled
immediately, then that exception is propagated or thrown to the caller of that
method. This propogation continues till it finds an appropriate exception
handler,if it finds handler it would be handled otherwise program terminates
abruptly.public class Main {
public static void main(String[ ] args) {
try {
int[] myNumbers = {1, 2, 3};
System.out.println(myNumbers[10]);
} catch (Exception e) {
System.out.println("Something went wrong.");
}
}
} - ArithmeticException
It is thrown when an exceptional condition has occurred in an arithmetic operation.
- ArrayIndexOutOfBoundsException
It is thrown to indicate that an array has been accessed with an illegal index. The index is either negative or greater than or equal to the size of the array.
- ClassNotFoundException
This Exception is raised when we try to access a class whose definition is not found
- FileNotFoundException
This Exception is raised when a file is not accessible or does not open.
- IOException
It is thrown when an input-output operation failed or interrupted
- InterruptedException
It is thrown when a thread is waiting, sleeping, or doing some processing, and it is interrupted.
- NoSuchFieldException
It is thrown when a class does not contain the field (or variable) specified
- NoSuchMethodException
It is thrown when accessing a method which is not found.
- NullPointerException
This exception is raised when referring to the members of a null object. Null represents nothing
- NumberFormatException
This exception is raised when a method could not convert a string into a numeric format.
- RuntimeException
This represents any exception which occurs during runtime.
- StringIndexOutOfBoundsException
It is thrown by String class methods to indicate that an index is either negative or greater than the size of the stringpublic class JavaExceptionExample{
public static void main(String args[]){
try{
//code that may raise exception
int data=100/0;
}catch(ArithmeticException e){System.out.println(e);}
//rest code of the program
System.out.println("rest of the code...");
}
} try {
System.out.println("I am in try block");
} catch(Exception ex){
ex.printStackTrace();
} finally {
System.out.println("I am in finally block");
}