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Custom Exception

Custom Exception

In Java, you can create your own custom exception classes by extending the built-in Exception class (for checked exceptions) or RuntimeException class (for unchecked exceptions).

Custom Exceptions are important because:
  • To represent application-specific errors
  • To provide meaningful messages and structured error handling
  • To make code cleaner and easier to debug
    •     class MyException extends Exception{
    MyException(){
        super();
    }
    MyException(String s){
        super(s);
    }
}

class MyException_demo{
    public static void checkNum(int x) throws MyException{
        if(x % 2 == 0)
            throw new MyException("Even not required!");
    }
    public static void main(String[] aar){
        
        int[] ids = {1,2,3,4,5,6};
        try{
            checkNum(21); //If even number is given Custom Exception will be thrown
            for(int x: ids){
                if(x > 5) //if x is greater than 5 exception will be thrown
                    throw new MyException("Greater than 5");
            }
        }catch(MyException e){
            System.out.println(" Excep: "+e.getMessage());
        }
    }
}