Defining Methods

Learn how to declare/define methods in Java

The method definition follows the pattern

MODIFIERS     RETURN_TYPE    METHOD_NAME   (PARAMETERS)      EXCEPTIONS_THROWN {

//More code here

}

Let us have look at the below example.

The method name and the parameters are together called Method Signature.

The below method accepts 2 parameters. Multiple parameters are separated by comma.

 public double getDiscount(double labelPrice, boolean isSeniorCitizen) throws Exception {
        if (labelPrice < 0.0) {
            throw new Exception("Price Cannot Be A Negative Amount");
        }

        //20% discount for senior citizen
        if (isSeniorCitizen) {
            return 0.8 * labelPrice;
        }

        //Discount is 10%
        return 0.9 * labelPrice;
    }

Note: We will explain more about Exception in later chapters.