1. CSC305: COMPUTER PROGRAMMING II (JAVA)
AJAYI, O. O.

2. INTRODUCTION Intro to JAVA as an Object-Oriented Programming Language.
Intro the Structure of Java
Intro to Data Types in Java
Intro to Java I/O Statements

3. INPUT Statement The NEEDFUL… …using SCANNER IMPORT TEMPORAL Scanner
ASSIGNMENT

4. ILLUSTRATION
Write a Java program that accepts values for two integer variables and compute their summation.

5. STEPS & SOLUTION STEPS… Click FILE  NEW PROJECT
Under CATEGORY, select JAVA
Under PROJECT, select JAVA APPLICATION
Click NEXT
Under PROJECT NAME, specify your desired name
If needful, specify the directory for storing/saving your file OR use the default
Click FINISHED

6. The look…
Depending on your IDE type, you should be having something like this now…
package mywork1;
public class Mywork1 {
public static void main(String[] args) {
……TODO – your coding goes here }

7. NEXT… Note however, your IMPORT Statement
package mywork1;
import java.util.Scanner;
public class Mywork1 {
public static void main(String[] args) {
……TODO – your coding goes here }

8. Gradual Coding now- Illustration
I/O Statements in Java
import java.util.Scanner; //under package…
Public class………..{
Public static void main (String args[]){
int a,b,sum;
Scanner getin = new Scanner (System.in);
System.out.print(“Input me: ”);
a = getin.nextInt();
System.out.print(“Input the other: ”);
b = getin.nextInt();
sum = a+b;
System.out.printf(“The summation of a and b is %d”, sum); }

9. I/O Statement cont’d I/O Statements in Java GUI Method Steps:
Import the JOptionPane using javax.swing.JOptionPane;
Access the GUI either for:
Inputting (showInputDialog…….), OR
Outputting (showMessageDialog……)

10. Illustration I: A Java Program to capture and welcome user’s ID
public class ……….. {
public static void main(String[] args) {
String username;
username = JOptionPane.showInputDialog("Enter Username: ");
JOptionPane.showMessageDialog(null, "Welcome " +username, "AJ App", JOptionPane.ERROR_MESSAGE); }

11. Illustration II: A Java Program to capture values for two integers (using GUI) and then compute their summation; OUTPUTTING it (i) on console (ii) via GUI
import java.util.Scanner; import javax.swing.JOptionPane; public class Mywork1 { public static void main(String[] args) { int a, b,sum; String a2, b2; a2 = JOptionPane.showInputDialog("Enter 1st No:"); b2 = JOptionPane.showInputDialog("Enter 2nd No:"); a = Integer.parseInt(a2); b = Integer.parseInt(b2); sum = a+b; System.out.printf("The sum is: %d", sum); }

12. Illustration II: OPTION II
import java.util.Scanner; import javax.swing.JOptionPane; public class Mywork1 { public static void main(String[] args) { int a, b,sum; String a2, b2; a2 = JOptionPane.showInputDialog("Enter 1st No:"); b2 = JOptionPane.showInputDialog("Enter 2nd No:"); a = Integer.parseInt(a2); b = Integer.parseInt(b2); sum = a+b; JOptionPane.showMessageDialog(null,"The sum total is" +sum, "AJ APP", JOptionPane.INFORMATION_MESSAGE); }

13. Weekend Practical Activities
Write a simple Java program that demonstrate the differences between PRINT, PRINTLN and PRINF Statements.
Aside +, -, *, / which are common arithmetic operators in Java and other programming languages, Java also has % for modulus computation. With this and with your knowledge of iterative statement like do-while, while & for statement, write a Java program that converts 5710 to base 2.
We would soon get to the chapter that deals with Control Statement. But I can tell you it’s the same as in C++. Review the use of Switch Statement in C++ and deploy the knowledge to write a PHONE BATTERY STATUS program such that when the battery power % is >=70 u report ‘battery can carry thru to the desert’, <70 but >29, ‘be moving close to power source’, <30 but >19, ‘am weak & thirsty for refilling’, <20 but >4, ‘I will soon disappoint u’, else ‘u succeeded in killing me, wicked owner’.