Writing Methods

Writing Methods

Method Definition

  • A method is a collection of statements that perform some operation.
  • It is defined within a class and represents the behaviour of an object of that class.

Method Declaration Format

  • The format typically is:
accessModifier returnType methodName(parameters) {
    // body of the method
}
  • The access modifier (such as public or private) controls the access level of the method.
  • returnType is the data type that the method returns. If the method does not return a value, its returnType is void.
  • The methodName is the identifier that is used to call the method.
  • parameters are the list of variables defined by their type and name that this method receives.

Invoking a Method

  • A method is invoked (called) using the his method name and the parameters needed by the method.

Method Behaviour and Control Flow

  • Statements inside a method are executed sequentially from top to bottom.
  • A method can call other methods, create variables, and perform calculations, among other actions.
  • Control structures like loops and conditional statements can be included in a method to guide its execution flow.

Parameters and Arguments

  • Parameters are variables defined by the method during its declaration.
  • Methods can be invoked with arguments, data values passed to the method during its call.
  • The number and type of arguments supplied when calling a method must match the number and type of parameters defined by the method declaration.

Return Statement

  • A return statement is used to conclude a method’s execution and potentially pass a value back to its calling statement.
  • The type of this returned value must match the returnType declared in the method header.

Importance of Methods

  • Methods allow for code reuse, so similar operations only need to be written once.
  • By clearly defining methods with precise behaviours, one can construct complex applications using a modular and organised approach.
  • Proper use of methods promotes the OOP principle of Encapsulation, ensuring data is safely accessed and modified.