Question

Write a simple Java program with the following naming structure:

• Open Eclipse
• Create a workspace called hw1
• Create a project called hw1 (make sure you select the “Use project folder as root for sources and class files”)
• Create a class called Hw1 in the hw1 package (make sure you check the box that auto creates the main method).
• Add a comment to the main that includes your name

Write code that demonstrates the use of each of the following basic Java commands.

Before each line or block of code add a comment with the number of the task. For example, 1. below might look like this:

//1
System.out.print("this is the easiest homework assignment ever!");

• System.out.print
• System.out.println
• Outputting a string literal
• Using "\t" and "\n"
• Using + to concatenate two things inside a print
• Creating an int, double, boolean and char primitive variables
• Storing values into the previous variables
• Creating a String object
• Storing a string into the String object
• Print all of the previously created variables and the String object and separated by tabs
• Show how to make a variable a constant
• Create a Scanner object
• Use the Scanner object to read from the keyboard an int, double, char and String and store the values into the previously declared variables. (char is difficult. Research / Google how to do this...)
• Print the variables again, and separated by tabs
• Use three of the Math class methods
• Create a use a Random object to print a random number between 10 and 20 inclusively
• Show an example of data type conversion without explicit casting
• Show an example of data type conversion with casting
• Show the use of an if statement comparing two primitives
• Show the use of the .equals() method inside an if statement to compare two Strings
• Show the use of an if-else statement
• Use a For loop to print the numbers from 1 to 20 inclusively and all on the same line
• Use a While loop to print the even numbers from 1 to 61 and all on the same line
• Use a Do-While loop to prompt the user to enter an odd positive number
• Create an int array that can hold 100 values. Fill it will random numbers between 0 and 300.
• Find and print the smallest number in the int array.
• Find and print the average of the numbers in the int array.

Answer 1

Code -

import java.util.*;
public class Main
{
   public static void main(String[] args) {
   //1
   System.out.print("this is the easiest homework assignment ever!\n");
   //2 println
   System.out.println("This print the code and bring cursor to new line.");
   //3 \t and \n
   System.out.println("\tThis give a tab space and \n is used to print to new line");
   //4 + to concantenate two String
   System.out.print("Using +"+" to concantenate strings \n");
   //5 int double char
   int integerNum;
   double doubleNum;
   char character;
   //6 storing values
   integerNum = 5;
   doubleNum = 10.54;
   character = 'A';
   //7 String object
   String str1;
   //8 storing string in string object
   str1 = new String("New string created");
   //9 print all variables
   System.out.println(integerNum+"\t"+doubleNum+"\t"+character+"\t"+str1);
   //10contant variables using static final keyword
   final int a = 10;
   //11 Scanner object
   Scanner sc = new Scanner(System.in);
   //12 store value
   System.out.println("Enter int double char and string to store in variable");
   integerNum = sc.nextInt();
   doubleNum = sc.nextDouble();
   character = sc.next().charAt(0);
   str1 = sc.next();
   //13 print variable again
   System.out.println(integerNum+"\t"+doubleNum+"\t"+character+"\t"+str1);
   //14 Math class
   int min = Math.min(10, 20); //print 10
   double floor = Math.floor(7.343); // floor = 7.0
   double squareRoot = Math.sqrt(4); //squareRoot = 2
   //15Random number in range 20 to 30
   Random r = new Random();
       int rand = r.nextInt(11) + 10;
      
       //16Implicit casting or without explicit casting -
       int x = 10; // occupies 4 bytes
double y = x; // occupies 8 bytes
System.out.println(y); // prints 10.0
     
   //17Explicit casting
   double xx = 10.5;
int yy = (int) xx;//print 10
System.out.println(yy);
     
   //18if statement comparing primitive
   if(10>5){
   System.out.println("10 is greater than 5");
   }
  
   //19 equals
   String s1 = "John";
   if(s1.equals("John")){
   System.out.println("String are equal");
   }
  
   //20 if else
   if(10>20){
   System.out.println("10 is greater than 20");
   }
   else{
   System.out.println("10 is less than 20");
   }
  
   //21 for loop
   for(int i = 1; i <=20;i++){
   System.out.print(i+" ");
   }
  
   //22while loop
   int count = 1;
   while(count<=61){
   if(count%2==0){
   System.out.print(count+" ");
   }
   count++;
   }
  
   //23 do while
   int number;
   do{
   System.out.println("Enter an odd positive number");
   number = sc.nextInt();
   }while(number%2==0 || number<0);
  
   int arr[] = new int[100];
   for(int i = 0; i <arr.length;i++){
   arr[i] = r.nextInt(301);
   }
   //24smallest
   int smallest = 10000;
   for(int i = 0; i <arr.length;i++){
   if(smallest>arr[i]){
   smallest = arr[i];
   }
   }
   System.out.println("smallest is "+smallest);
  
   //25 average
   int average,total=0;
   for(int i = 0; i <arr.length;i++){
   total+=arr[i];
  
   }
   average = total / arr.length;
   System.out.println("Average is "+average);
  
   }
}

Screenshots-

pls do give a like thank you