Java Project #9: Pay Raise

/**
 * PayRaise computes pay raise and new salary for employees.
 * 
 * @author (Andrew Samuels) 
 * @version (02-19-2010)
 */

//import scanner
import java.util.Scanner;

public class PayRaise
{

    public static void main(String[] args)
    {
        //create variables
        double currentSalary;
        double payRaise;
        double newSalary;
        String word;
        char performanceRating;
        
        //create scanner
        Scanner keyboard = new Scanner(System.in);
        
        //capture current salary from user
        System.out.print("Please enter current salary: ");
        currentSalary = keyboard.nextDouble();
        
        //capture performance rating from user
        System.out.print("Please enter performance rating (A, B, C): ");
        word = keyboard.next();
        performanceRating = word.charAt(0);
        
        //determine pay raise using switch/case
        switch(performanceRating)
        {
            case 'A':
                payRaise = currentSalary * .06;
                newSalary = currentSalary + payRaise;
                System.out.println("Pay raise is: " + payRaise);
                System.out.println("New salary is: " + newSalary);
                break;
            case 'B':
                payRaise = currentSalary * .04;
                newSalary = currentSalary + payRaise;
                System.out.println("Pay raise is: " + payRaise);
                System.out.println("New salary is: " + newSalary);
                break;
            case 'C':
                payRaise = currentSalary * .02;
                newSalary = currentSalary + payRaise;
                System.out.println("Pay raise is: " + payRaise);
                System.out.println("New salary is: " + newSalary);
                break;
            default:
                System.out.println("Invalid performance rating");
        }
    }
}

Java Project #8 : Tax Program

/**
 * TaxProgram compute tax according to marital status and income.
 * 
 * @author (Andrew Samuels) 
 * @version (02-19-2010)
 */

//import scanner
import java.util.Scanner;

public class TaxProgram
{

    public static void main(String[] args)
    {
        //create variables
        int income;
        int taxAmount;
        String maritalStatus;
        
        //create scanner
        Scanner keyboard =  new Scanner(System.in);
        
        //capture income from user
        System.out.print("Please enter income: ");
        income = keyboard.nextInt();
        
        //capture marital status from user
        System.out.print("Please enter marital status (single, married): ");
        maritalStatus = keyboard.next();
        
        //determine tax amount from marital status and income
        if ((maritalStatus.equals("single") || maritalStatus.equals("Single")) && income < 30000)
        {
            taxAmount = income * 1/5;
            System.out.println("Tax amount is: " + taxAmount);
        }
        else if ((maritalStatus.equals("single") || maritalStatus.equals("Single")) && income > 30000)
        {
            taxAmount = income * 1/4;
            System.out.println("Tax amount is: " + taxAmount);
        }
        else if ((maritalStatus.equals("married") || maritalStatus.equals("Married")) && income < 50000)
        {
            taxAmount = income * 1/10;
            System.out.println("Tax amount is: " + taxAmount);
        }
        else if ((maritalStatus.equals("married") || maritalStatus.equals("Married")) && income > 50000)
        {
            taxAmount = income * 3/20;
            System.out.println("Tax amount is: " + taxAmount);
        }
    }
}

Java Project #7 : Student Grades (Upgraded!)

/**
 * StudentGrades computes the grades of students in a class.
 * 
 * @author (Andrew Samuels) 
 * @version (02-18-2010)
 */

//import scanner
import java.util.Scanner;

public class StudentGrades
{
    
    public static void main(String[] args)
    {
        //create variables
        int homeworkScore;
        int midtermScore;
        int finalexamScore;
        double finalcourseScore;
        
        //create scanner
        Scanner keyboard = new Scanner(System.in);
        
        //capture total homework score from user
        System.out.print("Please enter total homework score (0-200): ");
        homeworkScore = keyboard.nextInt();
        
        //capture midterm score from user
        System.out.print("Please enter midterm score (0-100): ");
        midtermScore = keyboard.nextInt();
        
        //capture final exam score from user
        System.out.print("Please enter final exam score (0-100): ");
        finalexamScore = keyboard.nextInt();
        
        //determine final course score
        finalcourseScore = (50*(homeworkScore/200.0) + 20*(midtermScore/100.0) + 30*(finalexamScore/100.0));
        
        //print final course score
        System.out.println("Final course score is: " + finalcourseScore);
        
        //determine letter grade and meaning of the grade
        if (finalcourseScore >= 90 && finalcourseScore <= 100)
        {
            System.out.println("Letter grade is: A");
            System.out.println("You are: Distinctly above average");
        } 
        else if (finalcourseScore >= 80 && finalcourseScore < 90)
        {
            System.out.println("Letter grade is: B");
            System.out.println("You are: Above average");
        }
        else if (finalcourseScore >= 70 && finalcourseScore < 80)
        {
            System.out.println("Letter grade is: C");
            System.out.println("You are: Average");
        }
        else if (finalcourseScore >= 60 && finalcourseScore < 70)
        {
            System.out.println("Letter grade is: D");
            System.out.println("You are: Below average");
        }
        else if (finalcourseScore >= 0 && finalcourseScore < 60)
        {
            System.out.println("Letter grade is: E");
            System.out.println("You are: Failed");
        }
    }
}

Java Project #6 : Points Distance

/**
 * PointsDistance computes the distance between two points in the two dimensional plane.
 * 
 * @author (Andrew Samuels) 
 * @version (02-04-2010)
 */

//import Scanner from library
import java.util.Scanner;

public class PointsDistance
{
    public static void main(String[] args)
    {
        //create distance formula variables
        double x1;
        double y1;
        double x2;
        double y2;
        double distanceBetweenPoints;
        
        //Create Scanner
        Scanner keyboard = new Scanner(System.in);
        
        //capture x1 from user
        System.out.print("Please enter x coordinate of first point: ");
        x1 = keyboard.nextDouble();
        
        //capture y1 from user
        System.out.print("Please enter y coordinate of first point: ");
        y1 = keyboard.nextDouble();
        
        //capture x2 from user
        System.out.print("Please enter x coordinate of second point: ");
        x2 = keyboard.nextDouble();
        
        //capture y2 from user
        System.out.print("Please enter y coordinate of second point: ");
        y2 = keyboard.nextDouble();
        
        
        //calculate distance between points using distance forumula
        distanceBetweenPoints = Math.sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
        
        
        //print distance between the points
        System.out.println("Distance between (" + x1 + ", " + y1 + ") and (" + x2 + ", " + y2 +") is: " + distanceBetweenPoints);
    }
}

Java Project #5 : Bank Investment

/**
 * BankInvestment computes the total money earned in an investment bank.
 * 
 * @author (Andrew Samuels) 
 * @version (02-04-2010)
 */
//importing Scanner from library
import java.util.Scanner;

public class BankInvestment
{
    public static void main(String[] args)
    {
    //create variables
    int initialInvestmentMoney; //initial investment money in dollars
    double interestRate; //interest rate in percentage
    int numberOfYears; //number of years of investment
    double totalMoneyEarnedDouble; //total money earned, double type, (converted to integer later)
    
    //Create Scanner
    Scanner keyboard = new Scanner(System.in);
        
    //capture initial investment from user
    System.out.print("Please enter initial investment (dollars): ");
    initialInvestmentMoney = keyboard.nextInt();
    
    //capture interest rate from user
    System.out.print("Please enter interest rate (percent): ");
    interestRate = keyboard.nextDouble();
    
    //capture numbers of years of investment from user
    System.out.print("Please enter years of investment (years): ");
    numberOfYears = keyboard.nextInt();
    
    //Calculate total money earned with formula p(1 + r/100)^n
    totalMoneyEarnedDouble = initialInvestmentMoney*(Math.pow(1 + interestRate/100, numberOfYears));
    
    //convert total money earned from double to integer
    int totalMoneyEarned = (int)totalMoneyEarnedDouble;
    
    //print total money earned
    System.out.println("The total money earned (dollars): " + totalMoneyEarned);
    }
}

Java Project #4: Travel Cost

/**
 * TravelCost computes the cost of travel using a vehicle.
 * 
 * @author (Andrew Samuels) 
 * @version (02-04-2010)
 */

//importing Scanner from library
import java.util.Scanner;

public class TravelCost
{
    public static void main(String[] args)
    {
    //create variables
    int travelDistance; //travel distance in miles
    int gasolineUsage; //gasoline usage in miles per gallon
    double gasolinePrice; //gasoline price in dollars per gallon
    double totalTravelCost; //The total cost of traveling
    
    //Create Scanner
    Scanner keyboard = new Scanner(System.in);
        
    //capture travel distance from user
    System.out.print("Please enter travel distance (miles): ");
    travelDistance = keyboard.nextInt();
    
    //capture gas usage from user
    System.out.print("Please enter gas usage of vehicle (miles per gallon): ");
    gasolineUsage = keyboard.nextInt();
    
    //capture gas price from user
    System.out.print("Please enter gas price (dollars per gallon): ");
    gasolinePrice = keyboard.nextDouble();
    
    //Calculate
    totalTravelCost = (travelDistance/gasolineUsage)*gasolinePrice;
    
    //print total travel cost
    System.out.println("The total travel cost (dollars): " + totalTravelCost);
    }
}

Java Project #3 : Student Grade

/**
 * StudentGrade determines the final semester score of students in a course.
 * 
 * @author (Andrew Samuels) 
 * @version (02-01-2010)
 */
//import scanner class
import java.util.Scanner;

public class StudentGrade
{

    public static void main(String[] args)
    {
        //initialize variables
        int programs;
        int homeworks;
        int examinations;
        double finalSemesterScore;
        
        //create scanner
        Scanner keyboard = new Scanner(System.in);
        
        //input total program score from the user
        System.out.print("Please enter total program score (0-200): ");
        programs = keyboard.nextInt();
        
        //input total homework score from the user
        System.out.print("Please enter total homework score (0-500): ");
        homeworks = keyboard.nextInt();
        
        //input examination score from the user
        System.out.print("Please enter examination score (0-100): ");
        examinations = keyboard.nextInt();
        
        //calculate final semester score
        finalSemesterScore = 50*(programs*.005) + 30*(homeworks*.002) + 20*(examinations*.01);
        
        //print final semester score
        System.out.println("Final semester score is: " + finalSemesterScore);
        
        
    }
}

Java Project #2 : Coinjar

Got spare change in the piggie jar? Coinjar is a Java script that determines the value of coins in a jar. Tell it how many quarters, dimes, nickels, and pennies you have and it will spit out the dollar value.

/**
 * CoinJar determines the value of coins in a jar.
 * 
 * @author (Andrew Samuels) 
 * @version (02-01-2010)
 */
//import scanner class
import java.util.Scanner;

public class CoinJar
{

    public static void main(String[] args)
    {
        //create currency variables in pennies
        int quarters = 25;
        int dimes = 10 ;
        int nickels = 5;
        int pennies = 1;
        
        //create variables for user number of change
        int quartersNumber;
        int dimesNumber;
        int nickelsNumber;
        int penniesNumber;
        
        //create variables for value of change
        int quartersTotal;
        int dimesTotal;
        int nickelsTotal;
        int penniesTotal;
        
        //variables for total value as double
        int totalValue;
        double dollarCents;
        
        
        //create scanner
        Scanner keyboard = new Scanner(System.in);
        
        //input quarters from the user
        System.out.print("Please enter number of quarters: ");
        quartersNumber = keyboard.nextInt();
        
        //input dimes from the user
        System.out.print("Please enter number of dimes: ");
        dimesNumber = keyboard.nextInt();
        
        //input nickels from the user
        System.out.print("Please enter number of nickels: ");
        nickelsNumber = keyboard.nextInt();
        
         //input pennies from the user
        System.out.print("Please enter number of pennies: ");
        penniesNumber = keyboard.nextInt();
        
        //calculate quarters value
        quartersTotal = quarters*quartersNumber;
    
        //calculate dimes value
        dimesTotal = dimes*dimesNumber;
        
        //calculate nickels value
        nickelsTotal = nickels*nickelsNumber;
        
        //calculate pennies value
        penniesTotal = pennies*penniesNumber;
        
        //calculate total value in pennies
        totalValue = quartersTotal + dimesTotal + nickelsTotal + penniesTotal;
        
        //calculate total value as double in dollarCents ex. 2.19
        dollarCents = totalValue*(.01);
        
        //convert dollarCents to String for later use.
        String dollarCentsStr;
        dollarCentsStr = "" + dollarCents;
        
        //convert to dollarCents into integer
        int dollarCentsInt = (int)dollarCents;
        
        //separate cents using substring
        String number = dollarCentsStr;
        String result;
        result = number.substring(2);
       
        //print total dollars and cents
        System.out.println("Jar has " + dollarCentsInt + " dollars and " + result + " cents");
        
        
    }
}

Java Project #1 : The Sphere Problem

This is a straightforward problem. This little ditty computes the volume and surface area of a sphere. Java is fun, no?

/**
 * SphereProblem reads the radius of a sphere from the user and computes its volume and surface area, then prints them out..
 * 
 * @author (Andrew Samuels) 
 * @version (02-01-2010)
 */
//import scanner class
import java.util.Scanner;

public class SphereProblem
{

    public static void main(String[] args)
    {
        //initialize variables
        double radius; //radius of a sphere
        double volume; //volume of a sphere
        double area; //area of a sphere
        double PI = 3.1415;
        
        //create scanner
        Scanner keyboard = new Scanner(System.in);
        
        //input radius from the user
        System.out.print("Please enter radius of a sphere: ");
        radius = keyboard.nextDouble();
        
        //calculate volume
        volume = (4/3)*PI*radius*radius*radius;
    
        //calculate area
        area = 4*PI*radius*radius;
        
        //print volume
        System.out.println("Volume of sphere is: " + volume);
        
        //print area
        System.out.println("Area of sphere is: " + area);
        
    }
}