Java Inventory Program problems

I have 2 error messages that I am having trouble figuring out what it is asking me for. The errors are:

Desktop\Inventory Program\InventoryPart1.java:93: cannot find symbol
symbol  : variable printer
location: class InventoryPart1
        System.out.println("Item Number: " + printer.getItemNumber());


Desktop\Inventory Program\InventoryPart1.java:95: cannot find symbol
symbol  : variable printer`enter code here`
location: class InventoryPart1
        System.out.println("Product Name: " + printer.getProductName());

The code so far is

import java.text.NumberFormat;
import java.util.locale;
import java.util.Scanner;


class Printer {

    private String itemNumber;
    private String productName;
    private double units;
    private double unitPrice;
    private double unitsTotal;
    //constructor
    public Printer (String itemNumber, String productName, double units, double unitsTotal) {

        setItemNumber(itemNumber);
        setProductName(productName);
        setUnits(units);
        setUnitPrice(unitPrice);
        unitsTotal = units ++;
    }

    //accessor methods for class variables
    public String getItemNumber () {
        return itemNumber;

    }

    public void setItemNumber (String itemNumber) {
        this.itemNumber = itemNumber;
    }

    public String getProductName () {
        return productName;
    }


    public void setProductName (String productName) {
        this.productName = productName;
    }

    public double getUnits () {
        return units;
    }

    public void setUnits (double units) {
        this.units = units;

    }

    public double getUnitPrice () {
        return unitPrice;
    }

    public void setUnitPrice (double unitPrice) {
        this.unitPrice = units * unitPrice;
    }


    public double getUnitsTotal () {
        return unitsTotal;
    }

    public void setUnitsTotal (double unitsTotal) {
        this.unitsTotal = units ++;
    }


}


public class InventoryPart1 {

    public static void main (String args[]) {


        int units;

        double unitPrice;


        double unitsTotal;
        unitsTotal = units ++;

        double unitsPrice;
        unitsPrice = units * unitPrice;

        double unitsTotalPrice;
        unitsTotalPrice = unitsTotal * unitPrice;

        double totalInventory;

        totalInventory = unitsTotal * unitsTotalPrice;


        NumberFormat nf = NumberFormat. getCurrencyInstance(Locale.US);

        //create an instance of the Printer class
        Printer epson = new Printer ("Epson579", "All In One", 2, 50.99);

        //use the methods from class Printer to output the inventory details.
        System.out.println("Item Number: " + printer.getItemNumber());


        System.out.println("Product Name: " + printer.getProductName());

        System.out.print("Number of Units: ");
        System.out.println(nf.format(units));

        System.out.print("Unit Price: ");
        System.out.println(nf.format(unitPrice));

        System.out.print("Units Total: ");

        System.out.println(nf.format(unitsTotal));

        System.out.print("Units Total Price: ");
        System.out.println(nf.format(unitsTotalPrice));

        System.out.print("Total Inventory: ");
        System.out.println(nf.format(totalInventory));
    }

}

Sorry new to this site and still trying to figure things out with the whole code entering,