Science Computer (SC025)

In Semester 2, we will study about JAVA program. JAVA is a general-purpose programming language that is class-based, object-oriented, and designed to have as few implementation dependencies as possible. It is not hard to learn if we focus well during class hours and do as many question possible😇
                                          

  -This module will give you a very brief explaination about How To Learn Java 🙏                                 https://drive.google.com/open?id=1gYJSdni2mYNRFlkqVXBTKHMz5fygK-dd

Chapter 1 ➤APPROACH IN PROBLEM SOLVING

(A) Notes

https://drive.google.com/open?id=1Ytv7-gaJ36cr1dbDooUvsVX7IRlgg8FQ

(B) Exercise

https://drive.google.com/open?id=1E2wY4l6EDtWjJaqCBkhxUa_GQldPjJPs

(C) Simple Revision Notes

TOPIC 1 : APPROACH IN PROBLEM SOLVING

Chapter 2 ➤DESIGN SOLUTION

(A) Notes

https://drive.google.com/open?id=1hb9dbgzNRI2wL9e0ZVaT2CiaSvUacuJ4

(B) Exercise
https://drive.google.com/open?id=1HTa8l9m7rIfxdN_pbYaPpXh9zCGEi0WP

Technique To Answer Repetition Question

(C) Simple Revision Notes 

TOPIC 2 : DESIGN A SOLUTION

v  ALGORITHMS :-

Well defined procedure that allows a computer to solve a problem

Ways to present :-

(A) Pseudocode

(B) Flowchart (Graphical representation of problem solving)

v  Pseudocode :-

(A) Semiformal, English-like language with a limited vocabulary that can be used to design an algorithm

(B) Purpose : To define the procedural logic of an algorithm in a simple and easy to understand for readers who are not proficient in computer programming language.

v  Control Structure :-

(A) Block of programming that analyse variable and choose direction based on given parameters.

(B) Sequence, Selection and Repetition

(C) Sequence : All actions will be executed sequentially

(D) Selection :-

      (i) Single Selection

      (ii) Dual Selection

      (iii) Multiple Selection

*there can be if without else but there cannot be else without if

(E) Repetition :-

      (i) will be represented by using keyword while

      (ii) Counter-controlled repetition

            (1) Initialization : Set the initial value of the loop control variable 

            (2) Evaluation : Test the loop control variable to determine whether the loop      

                                        should continue or stop

            (3) Updating : Increment / Decrement the value of the loop control variable

      (iii) Loop Control Variable 

             : Variable that control the number of times the loop is executed

      (iv) Sentinel-controlled repetition

             : number of loop is NOT known before loop begins executing 

             : the loop will stop when sentinel value is reached

(F) Desk Checking : 

     (i) Informal manual test that programmers can use to verify coding

     (ii) Enable to spot errors that might prevent a program from working as it should

Chapter 3 ➤JAVA LANGUAGE

(A) Notes
https://drive.google.com/open?id=1FkJdn-yOZRMd0AMzfcdPPyMUwQMnn87_

(B) Exercise
https://drive.google.com/open?id=1AysGrsioz0TLCMUEwxfe805h0eEfT9I6

(C) Simple Revision Notes

3.1 INTRODUCTION TO JAVA

Object-Oriented Program (OOP)

- A programming technique that uses objects to design the applications and computer programs.

(1) Characterictics:-

(a) Abstraction
- Is a process of hiding the implementation details and showing only functionality to the user
- Purpose : Allow efficient design and implementation of complex software systems.

(b) Encapsulation
- Is a process of wrapping code and data together into a single unit
- Purpose : Wrap its inner attributes from outside the object
                : Allow behaviors to be accessible outside the object

(c) Inheritance
- Is a mechanism in which one object acquires all the properties and behaviors of a parent object
- Purpose : It’s the ability to create a new class from an existing class

(d) Polymorphism
- Is the ability to appear in many forms
- Purpose : Helps programmers reuse the code and classes once written, tested and implemented

(2) Class
 - Template or blueprint to create an object

(3) Object
- Is an identifiable entity with some characteristics and behavior
- It is an instance of a class
- Objects are specific and created from classes

3.1 DATA TYPE, OPERATOR AND EXPRESSION

(A) Identifier
- Words used to name constants, variables and functions
- Identifiers are formed by combining letters, digits and underscore

VALID	INVALID
income_tax	Student age
Item10	17throw
Count	Data-1
Number_of_students	Myfirst.c
ABC123Z7	12

(B) Variable
- Name given to the memory location where a value stored

(C) Constant
- Is an identifier that similar to a variable except that it holds one value while the program is active

(D) Primitive Data Types

Keyword	Description	Example	Java Statement
int	Integer	2, 4, 100	sc.nextInt( );
double	Floating point	74.5, 12.45	sc.nextDouble( );
boolean	Boolean value	True or False	sc.next( );
char	Single Character	1, A, 2	sc.next( ).charAt(0);
String	name	Nur izwani	sc.nextLine( );

(E) Operators
- Is a symbol which tells the compiler to take an action on operands and yield a value

Arithmetic Operation	Aritmetic Operator	Java Statement
Addition	+	a+b;
Subtraction	-	a-b;
Multiplication	*	a*b;
Division	/	a/b;
Modulus(Remainder)	%	a%b;

(F) Relational Operators
- To test the relation between two values

Relational Operation	Relational Operator
Equal to	= =
Less than	<
More than	>
Less than or equal	<=
More than or equal	>=
Not equal	!=

(G) Precedence

Operator	Precedence
( )	🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺         🔺                        Highest                                 🔺                 Lowest
!
*
/
% (Remainder)
+
-
<
<=
>
>=
= =
!=
&& (and)
| |  (or)
=

(H) Escape Characters
- Sequence begins with a backslash / followed by a character

Escape Sequence	Meaning
\n	A new line
\t	A tab
\”	A double square
\’	A single quote
\\	Backslash
\b	Backspace

3.2 ARRAY

Array
- A data structure that contains a group of elements.
- Purpose : To store multiple value of the same type using single variable
                : Enable you to write programs that manipulate larger amounts of data

(i) Declare A Variable

WITH BASIC TYPE	WITH AN ARRAY TYPE
int counts;	int [ ] counts;

(ii) Line of Code

DOUBLE LINE OF CODE	SINGLE LINE OF CODE
double [ ] values; values = new double [7]; String [ ] name; name = new String[7]; int [ ] num; num = new int[7];	double [ ] values = new double [7]; ------------------------------------------------- String [ ] name = new string [7]; ------------------------------------------------- int [ ] num = new int [7]; -------------------------------------------------

(iii) Reserved Word
: new/ return/ void/ int/ double/ boolean

3.3 METHODS

Method
- A component of a program/small program written to perform a specific task
- Advantage :-
  (i) Code reusability
      : Code written once can be used many times anywhere in the program
  (ii) Make code more readable and easier to debug
      : Segregrated into different smaller modules, locating the errors and correct easily
Type of method
   (a) Standard Library Methods
        - built-in methods in java and part of the compiler package

Math.sqrt(x);	String charAt(index), length ( )
Math.pow(x,y);	System methods- print( ), println( )
Scanner methods- next( ), nextInt( ), nextDouble( ), nextBoolean.

   (b) User – Defined Methods
         - Created by the programmer.These methods take-on names  that you assign to
            them and perform tasks that you create

Modifier	Define access type of the method and optional to use ( public static / private static )
Return Type Value	Method may return a value
Method Name	Method signature consists of the method name and the parameter list
Parameters	Variables in the method definition
Method Body	Defines what the method does with the statements

 
   (c) Class Name : The program class name
   (d) Object Name : The instance of the class
                                (object for the class name)
Method Return Type
 (a) Do not return a value
      :  uses the keyword void as return type in its heading to show that it does not
         return a value 
 (b) Return a value
      : returns a value must specify the type of that value in its heading

Argument	Parameters
- A value we pass to a method	- The variables in the method definition

Practical Notes (Array And Method)
➤➤https://drive.google.com/open?id=1RSq8VegYcbh_KeCXCYBaHV9Qpg2GtmIL

Youtube Video (Array)
➤➤https://youtu.be/w0_W5oDKQYI

Trial Set Paper 19/20

➤➤https://drive.google.com/open?id=1R1JBk0JzSBG5fmSCgGbghaH3ptHkyphA

96 Java Coding
(Selection, Sequence, Repetition, Array, Method)
➤➤https://drive.google.com/open?id=1-a8tUifwnrFow09K6_F-gxrzD97fFHKh

COMPLETED !😉💪