Java Programming

I having problems with a cannot find symbol error. I cant seem to figure it out.
I have about 12 of them in a program I am trying to do. I was wondering if anyone could help me out?

Here is some code I am working on:


// This will test the invoice class application.
// This program involves a hardware store's invoice.

//import java.util.*;

public class InvoiceTest
{
public static void main( String args[] )
{
Invoice invoice1 = new Invoice( "1234", "Hammer", 2, 14.95 );

// display invoice1
System.out.println("Original invoice information" );
System.out.println("Part number: ", invoice1.getPartNumber() );
System.out.println("Description: ", invoice1.getPartDescription() );
System.out.println("Quantity: ", invoice1.getQuantity() );
System.out.println("Price: ", invoice1.getPricePerItem() );
System.out.println("Invoice amount: ", invoice1.getInvoiceAmount() );

// change invoice1's data
invoice1.setPartNumber( "001234" );
invoice1.setPartDescription( "Yellow Hammer" );
invoice1.setQuantity( 3 );
invoice1.setPricePerItem( 19.49 );

// display invoice1 with new data
System.out.println("Updated invoice information" );
System.out.println("Part number: ", invoice1.getPartNumber() );
System.out.println("Description: ", invoice1.getPartDescription() );
System.out.println("Quantity: ", invoice1.getQuantity() );
System.out.println("Price: ", invoice1.getPricePerItem() );
System.out.println("Invoice amount: ", invoice1.getInvoiceAmount() );

}

}


and that uses this class file:


public class Invoice

{
private String partNumber;
private String partDescription;
private int quantityPurchased;
private double pricePerItem;

public Invoice( String ID, String desc, int purchased, double price )
{
partNumber = ID;
partDescription = desc;
if ( purchased >= 0 )
quantityPurchased = purchased;
if ( price > 0 )
pricePerItem = price;
}

public double getInvoiceAmount()
{
return quantityPurchased * pricePerItem;
}

public void setPartNumber( String newNumber )
{
partNumber = newNumber;
System.out.println(partDescription+" has changed to part "+newNumber);
}

public String getPartNumber()
{
return partNumber;
}

public void setDescription( String newDescription )
{
System.out.printf("%s now refers to %s, not %s.\n",
partNumber, newDescription, partDescription);
partDescription = newDescription;
}

public String getDescription()
{
return partDescription;
}

public void setPricePerItem( double newPrice )
{
if ( newPrice > 0 )
pricePerItem = newPrice;
}

public double getPricePerItem()
{
return pricePerItem;
}
}


Any tips for helping me out?