create exception java code example

Example 1: java define custom exception

public class CustomException extends Exception { 
    public CustomException(String errorMessage) {
        super(errorMessage);
    }
}

Example 2: java how to throw exception

public class ThrowException{
  public static void main(String [] args) throws Exception{ 
    //throws Exception line is needed if not using try-catch block
    throw new Exception("Errmessage");
  }
}

Example 3: what is exception in java

In java exception is an object. Exceptions are created when an abnormal 
situations are arised in our program. Exceptions can be created by JVM or 
by our application code. All Exception classes are defined in java.lang. 
In otherwords we can say Exception as run time error.