CE 277: Intro to Java Programming

• CE 277 is a Programming with Java course.
• The lecturers are Vincent M. Nofong, Albert K. K. Ansah, and Evans Obu.
• The course assessment comprises continuous assessment (40%) and end-of-semester examinations (60%).
• Continuous assessment includes attendance (10%), theoretical quizzes (10%), and practical quizzes and assignments (20%).
• End-of-semester examinations consist of written (30%) and practical (30%) components.
• Computers are electronic devices processing inputs to produce data.
• Modern computers contain: input devices, processors, storage devices, output devices, and software.
• An Operating System is a program that manages application programs and acts as an interface between application programs and hardware.
• An application program performs specific tasks.
• Programming languages are categorized into machine language, assembly language, high-level languages, etc.
• Machine language is the native language of computers, using binary code for instructions.
• Assembly language uses mnemonics to represent machine language instructions.
• Assemblers translate assembly language into machine code.
• High-level languages are platform-dependent, English-like, and use statements; examples include Java, C++, and Python.
• Interpreters and compilers translate source code into machine code.

Compiler vs Interpreter

• Interpreters read and execute source code statement by statement.
• Compilers translate the entire source code into a machine-code file before execution.
• Java was originally designed for consumer devices and is portable across different OS.
• Java has four platforms: Java SE, Java EE, Java ME, and JavaFX.
• Java SE develops client-side applications.
• Java EE develops server-side applications.
• Java ME develops applications for mobile devices.
• JavaFX creates rich internet applications with a user-interface API.
• Java includes an API, and language specifications available online.
• The Java Development Toolkit (JDK) is essential for Java development, containing tools like the Java Runtime Environment, compiler, etc.

Checking and Installing JDK Version

• Open command prompt or Powershell.
• Use the command java -version to see if java is installed.
• Use the command javac -version to check the version.

Java Path Configuration

• Access the system's environment variables to configure the Java Path.
• Locate the installed Java directory.
• Add the JDK bin directory to the system's Path variable.

Creating Java Codes and Testing in PowerShell

• Type the code
• Save file as MyFirstJavaCode.java
• Open PowerShell or Command Prompt
• Use the command javac MyFirstJavaCode.java and press Enter
• With not errors, use the command java MyFirstJavaCode and press Enter to run the code
• Students are advised to install the IntelliJ IDEA IDE.
• Different versions can be downloaded based on registration eligibility.

Elementary Programming

• A variable is a named storage location in a computer program used to hold a value of a specific data type.
• Variable declaration in Java includes specifying the data type as well as the name.
• Syntax of a variable is dataType variableName = value or dataType variableName.
• There are three types of variables: local, instance, and static.
• Local variables are inside a method.
• Instance variables are inside a class but outside a method and non-static.
• static variables are declared as static.
• Variable names start with a letter or _ and can not contain symbols or spaces, plus are case-sensitive.
• There are primitive and non-primitive data types.
• Primitive data types in Java include byte, short, int, long, float, double, char, and boolean.
• Assignment statements assign values to variables.
• Assignment expressions represent a computation through variables, operators, and values.

Arithmetic Operators

• Java supports add add, subtract, multiply, divide.
• Expressions can be represented as:
• f+7 / f-c / m * c / x/y / x mod y
• Precedence rules in Java: */% runs before +-.

Input Reading

• System.out refers to the standard output device.
• System.in refers to the standard input device.
• display information to the console, print, println.
• Scanner or BufferedReader classes can be used to create objects that read from console using System.in
• Scanner class can be used to create an object to read input from System.in Scanner input = new Scanner(System.in);
• Input objects must be closed when no longer in use.

Scanner Practical Steps

A Java program that when run:

• requires the user's name.
• accepts user input from the keyboard.
• displays a welcome message with the user's name.

numeric Data Types and operators

• Java: Six numeric datatypes, floats and integers.
• Integers include byte, short, int, long.
• Floating point includes float, and double.

Post/Pre increment and decrement data

• increment ++
• decrement --
• Given for example i = 2
• i++; is now 3
• j--; is now 1
• Example assume i = 1 int j = ++i; jis 2, i is 2 int j = i++; jis 1, i is 2 int j = -i; jis 0, i is 0 int j = i--; jis 1, i is 0

Numeric type conversion

• java assigns conversion of data from one numeric dat to another
• Always assign values of variable values based on value to an extend
• Casting converts value of one data type into another
• Casting provides widening
• Converting range from small numeric to larger, is expanding Small to large
• Narrowing large numerical code to smaller

Equality/Relational Operators

• Java supports operators testing realtionships of variables
• Algebraic operators can be equal
• Equality shows x == y , x is equal
• Relational provides x > y
• Relational operators also shows operators which are <, >=, <=, Practicals Create a java code to:
• Asks time and seconds entered an integer of the user
• Accept uses input, that converts from seconds into minutes
• Then converts the times from seconds into minutes, then displays results

Random numbers Generated in range

• Generates random number of 0 to 4
• Asks the user to guess the generated number
• Accept user's inputs
• Show "Correct, YOu Won"
• High Low show message
• The code shows "Correct Too Low" and the code is off
• The other one is too low

Write code that generates 2 digit imput

• Displays the first of many
• The second and number is multiple
• Mass index, measures the health factor based on weights
• Displays BMI

Mathematical Functions

• Useful Methods Math Class
• Trigorometic methods
• Exponent Functions and methods
• Math classes shows 2 double constant PI and E which is Math.PI and Math.E from data
• Trigonomic Data Java, the value is the support function Description
• sin()
• return the trigomoetric with radien values
• Cos() trigonomatric of andgle value
• Tan) returns trigonomatic value of the angles
• toRadians()
• toDegree()
• asin
• acos
• atan

Exponent Functoins

java shows 5 exponetial functions exponent loge log base 10 sqrt Methods

Exp(X)

• loge(x)
• returns as a natural logarithmis as x
• log10(x) Square Root

Service Functions

Function can support methods such as support, max with support the value

• Java has 4 rounding functions for values Method
• Cell method value is is to rounded intergated
• Floor to give function. Methods for ABS
• The method has a given set values.
• Random will show an eqaul set
• To generate values that are not given as the random values Char types and operations
• Computer are stored number in os and 1s, which store characters.
• Character is stored using the ASCII scheme.

Unicode

Character declariation char letter = 'B' the java statement will assign the varibale letter Esc value to show \(slash) is following digit

Coding, casting and converting

• Char is in every code, vice-versa
• Upper lower bit are coding process
• Upper, lower implicit
• Char can not be used, then coding required
• Comparing codes.

String Data Types

• Data is to store string sets
• Methods that for manipulation Method Description
• length() Char () concat
• returns number
• returns interger
• returns strings

Coverting functions

• The lower codes.
• Trim
• Returns String, and whitespace will be removed Statement loop if it is a true IF stateemnt has:
• ONEWAY codes
• Two way else statement
• If / else has condition
• If codes must statement to the condition Syntax, two way must else statemnts for the code Two if else statement is codnitional either true or force, the code example: if(condition) {Stateemnt} Else {states}

MultiWay -If, loop stateemnts Inner to code, that supports another

• There is no depth given to nesting of Multi way states

Logics

• Operation* ! && || X^ Exclusiv OR

• It provides states: If-If else to create codes Switch Statement Statement express if that it will the codes given that

Practicals 1

• Using one way if functions- show the JAVA, take input and show to be EVEN or ODD
• Double state and ranges 7.0 - Second 6.0-Second Class lower 5.0-Pass

Loops

3 Zodiacs with codes

• loops can statements for Java. That can the
• loop statements include will "Do while", "for,"

Do while loops vs WHILELOOPS

• Do While runs and has the While look and statements to follow for loop
• It can the code after iterations
• The loop is below codes*
• for{code}` For codes is a While and For loops as well