This Java code defines a PaintEstimate class with methods to calculate the costs for a paint job. It takes user input for the number of rooms, wall space, and paint cost per gallon. It then uses methods to calculate the gallons of paint needed, hours of labor, paint costs, labor costs, and total cost. The results are output along with job specifications. Key methods include calculateGallons(), calculateJobHours(), calculatePaintCharge(), and calculateLaborCharge().

1. JavaCode for Sample Projects
Methods Project
PaintEstimate.java File
importjavax.swing.JOptionPane;
importjava.text.DecimalFormat;
public class PaintEstimate
{
public static void main(String[] args)
{
String strNumberRooms;
intnumberRooms;
String strRoomWallsSqFt;
doubleroomWallSqFt;
doublelaborCostPerHour = 18;
String strGallonCost;
doublegallonCost;
doubletotalSquareFootage = 0 ;
doubletotalJobCharge = 0 ;
introomNumberCounter = 1;
doublenumJobGallons = 0;
doubletotalJobHours = 0;
doubletotalPaintCharge = 0;
doubletotalLaborCharge =0;
Methods Project Page 1

2. DecimalFormatdf = new DecimalFormat("0.00");
strNumberRooms = JOptionPane.showInputDialog("Welcome to the Painting Cost Estimator. Please enter the number of rooms
to be painted." );
numberRooms = Integer.parseInt(strNumberRooms);
while (roomNumberCounter<= numberRooms)
{
//take string input and convert to double
strRoomWallsSqFt = JOptionPane.showInputDialog("Please enter the total wall space in square feet for room #" +
roomNumberCounter );
roomWallSqFt = Double.parseDouble (strRoomWallsSqFt);
//increment total square footage variable
totalSquareFootage = totalSquareFootage + roomWallSqFt;
//increment roomNumberCounter
roomNumberCounter = roomNumberCounter + 1;
}
strGallonCost = JOptionPane.showInputDialog("Please enter the cost per gallon of the paint that you have selcted." );
gallonCost = Double.parseDouble(strGallonCost);
numJobGallons = calculateGallons (totalSquareFootage);
totalJobHours = calculateJobHours (totalSquareFootage);
totalPaintCharge = calculatePaintCharge (numJobGallons, gallonCost );
totalLaborCharge = calculateLaborCharge (totalJobHours, laborCostPerHour);
totalJobCharge = totalPaintCharge + totalLaborCharge;
Methods Project Page 2

3. System.out.println("PAINT COST ESTIMATE");
System.out.println("JOB SPECIFICATIONS: Number of Rooms: " + numberRooms + "; Total Wall Space: " + totalSquareFootage + "
square feet." );
System.out.println("COST PER GALLON OF PAINT SELECTED: $" + df.format(gallonCost));
System.out.println("TOTAL PAINT COST FOR JOB: $" + df.format(totalPaintCharge));
System.out.println ("TOTAL LABOR COSTS based on an estimate of " + df.format(totalJobHours) + " hours of labor at $" +
df.format(laborCostPerHour) + " per hour: $" + df.format(totalLaborCharge));
System.out.println("ESTIMATED TOTAL COST FOR PROJECT: $" + df.format(totalLaborCharge));
}
public static double calculateGallons (double sqFootage)
{
doublecoveragePerGal = 115;
doublenumGallons;
numGallons = sqFootage/coveragePerGal;
returnnumGallons;
}
public static double calculateJobHours (double sqFootage)
{
//double hoursPerSqFoot;
doublenumJobHours;
//
//convert given ratio of 8 hours to 115 sq feet to hours per sq foot
//hoursPerSqFoot = 8/115;
//apply number of hours per sq foot to total sq footage
//multiply total sq feet by conversion of hours to sq feet given
numJobHours = sqFootage * 8/115;
returnnumJobHours;
}
Methods Project Page 3

4. public static double calculatePaintCharge (double numGallons, double costPerGallon )
{
doublepaintCharge;
paintCharge = numGallons * costPerGallon;
returnpaintCharge;
}
public static double calculateLaborCharge (double numJobHours, double laborCostPerHour)
{
doubletotalLaborCost;
totalLaborCost = numJobHours * laborCostPerHour;
returntotalLaborCost;
}
}
Methods Project Page 4