Jeroo chapter 4
Download
1 / 17

Jeroo – Chapter 4 – - PowerPoint PPT Presentation


  • 126 Views
  • Uploaded on
  • Presentation posted in: General

Jeroo – Chapter 4 –. Simple Programs. Basic Concepts. Jeroo (Java/C++/object-oriented) programing style is case- sensative . Be consistent in coding Logic must be well designed Must be easy for someone to read and understand the program’s source code

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Jeroo – Chapter 4 –

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Jeroo – Chapter 4 –

Simple Programs


Basic Concepts

Jeroo (Java/C++/object-oriented) programing style is case-sensative.

Be consistent in coding

Logic must be well designed

Must be easy for someone to read and understand the program’s source code

Whitespace, comments, and descriptive identifiers all contribute to making a program easier to read.


Basic Concepts

  • Whitespace – consists of blank lines, spaces, tabs

    • Should be used to organize code into groups

    • Comments are phrases that a programmer inserts into a program to provide anyone who reads it additional information (Just like HTML)

      • Ignored when the program is run

      • Begins with // and continues until the end of the line


Form of a Jeroo ProgramMain Method

The main method describes how to use one or more Jeroos to solve a specific problem.

Everything that appears between the braces should be indented 2 or 3 spaces.

Method main ( )

{

…….

}


Declaring and Instantiating Jeroos

  • Every Jeroo program uses 1 to 4 Jeroo objects to solve a problem.

  • First declare the Jeroo, then Instantiate the Jeroo

    Jeroo name= new Jeroo(…);

  • For the declaration, the programmer must provide a name for the Jeroo object.

    • First character must be a letter, $, or underscore (_)

instantiation

declaration


Declaring and Instantiating Jeroos

  • Instantiation

  • A request that the Jeroo object be created

  • The crucial part is the constructor, which has the form of:

    • Jeroo (…)

  • The parentheses are filled with the initial values of the attributes for the Jeroo

  • Every Jeroo has 3 attributes: location, direction, number of flowers in its pouch.


Declaring and Instantiating Jeroos

  • If the initial values are not specified, then the constructor provides the default values:

    • Location – (0,0)

    • Direction – East

    • Flowers -- 0


Our code so far

method main ( )

{

Jerooname= new Jeroo(…);

}


Instantiation Portion

Now we will look at the code in red

Method main ()

{

Jeroojessica = new Jeroo(…)

}


Now our code…..

Method main ()

{

Jeroojessica = new Jeroo(2,5,North,4)

}

What is the default location?

How many flowers does Jessica have?

What direction is Jessica facing?


4.4 Action Statements

  • Is a request that a Jeroo perform a specific task.

  • The task can be either:

    • One of the basic action methods that are part of the Jeroo language

    • OR a Jeroo method that has been written by the program

  • We will concentrate on ones that are part of the Jeroo language.


Syntax of an action statement

jessica.hop(3)


Syntax of Action Statement

The Jeroo language inclues the 7 action methods shown on the next slide(s).

Three (3) of these: give, turn, hop require an argument value.

On the next slide, we will look at a table of actions


What happens in the following code?

Method main ( )

{

Jerooplace = new Jeroo ();

place.hop(4);

place.turn(RIGHT)

place.hop(2);

place.plant();


Answer these questions about the code?

What are the final coordinates of Jeroo place?

There is a logic error in the code. What is it?

There are two syntactical errors in the code. What are they?


ad
  • Login