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Methods and Abstraction

A method is a named sequence of instructions that can be referenced (invoked, called) in other places in the program through the use of a method (procedure) invocation statement.

Abstraction is a method of dealing with complexity by ignoring the details and differences and emphasizing similarities.

Methods were the first and simplest of the mechanisms developed in computer science to deal with the complexity of large systems. The use of methods in designing large systems is called procedural abstraction.

Advantages of Procedural Abstraction

Hides details.
Allows us to think about the general framework & postpone details for later.
Gives us building blocks we can reuse in other situations.
Lets us use local names.
Lets us easily replace implementations by better ones.

Example of Procedural Abstraction:

·The sum of squares is defined as Sn2 . Write a function sumSq which will accept an integer value n and return the sum of the squares from 1 to n. ·E.g. sumSq(3) should return 14. I.e. 12 + 22 + 32

Application to Mine Sweeper:

Programming the Mine Sweeper game is a complex procedure. In order to simply the programming process, the game should be broken down into smaller parts/methods (Procedural Abstraction). Some of the parts of this program may include:

Menu System - handling commands entered by the user
Randomly placing mines
Printing the game board to the screen
Determining if a selected cell contains a mine
Checking surrounding cells for mines