String output showing "null"

[hayden06f4i]

Hey guys, beginner here....(Again) here is the latest code i have (2 .java files) and my output it showing "null" for the Part # and part Description when it runs, im new and i don't know what im not doing correctly.

// Ex3.13 Invoice.java (JHtP page104)
//invoice a hardware store might use to represent an invoice
//for an item sold at the store

public class Invoice
{
	private String partNumber; // part number for invoice
	private String partDescription; //part description for invoice
	private int quantity; //number of parts being purchased
	private double pricePerItem; // price per item
	private double invoiceAmount; // total of quantity * priceperitem

	// 4-arg constructor
	public Invoice (String partNumber, String partDescription,
		int count, double price, double invoiceAmount)
	{
		setpartNumber ( partNumber );
		setpartDescription ( partDescription );
		
		if (count > 0) //determine whether count is positive
		quantity = count; // valid count assigned to quantity
		
		if (price > 0.0) // determine whether price is positive
		pricePerItem = price; // valid price assign to pricePerItem
		
		setquantity ( quantity );
		setpricePerItem ( price );
		setinvoiceAmount ( invoiceAmount );
	} // end 4-arg constructor
	
	// set Part number:
	public void setpartNumber ( String partNumber)
	{
		partNumber = partNumber; //accept the passed part value-assgn to  instance v partNumber
	}// end method setpartNumber
	
	// get Part number:
	public String getpartNumber ()
	{
		return partNumber;
	} //end method getpartNumber
	
	// set partDescription:
	public void setpartDescription ( String partDescription )
	{
		partDescription = partDescription; // accept the passed part value-assgn to  instance v partDesc
	}// end method setpartDescription
	
	//get partDescription:
	public String getpartDescription ()
	{
		return partDescription;
	}// end method getpartDescription
	
	// set quantity:
	public void setquantity ( int count)
	{
		quantity = count; 	
	}// end method set quantity
	
	// get quantity:
	public int getquantity ()
	{
		return quantity;
	} //end method get quantity
	
	// set pricePerItem
	public void setpricePerItem ( double price )
	{
		pricePerItem = price;
	}// end method set pricePerItem
	
	//get pricePerItem
	public double getpricePerItem ()
	{
		return pricePerItem;
	} // end method get pricePerItem
	
	//method to setInvoiceAmount
	public void setinvoiceAmount ( double invoiceAmount )
	{
		invoiceAmount = quantity * pricePerItem;
	}//end method set invoiceAmount
	
	
	// method to getinvoiceAmount (multiplies quantity * price per item) 
	public double getinvoiceAmount ()
	{
		return quantity * pricePerItem;
	}// end method getinvoiceAmount
} // end public class Invoice

program 2

// Ex3.13 InvoiceTest.java (JHtP page104)
//

public class InvoiceTest
{
	public static void main ( String args [] )
	{
		//create instance of Invoice passing 4 argument values
		Invoice invoice1 = new Invoice ( "1234" , "Hammer" , 5 , 14.99, 2 * 14.99 );
		
		//display invoice1
		System.out.println ("Original invoice information");
		
		System.out.printf ( "Part Number: %s\n", 
		invoice1.getpartNumber () );
		
		System.out.printf ( "Part Description: %s\n",
		invoice1.getpartDescription () );
		
		System.out.printf ( "Quantity: %s\n",
		invoice1.getquantity () );
		
		System.out.printf ( "Price Per Item: %s\n",
		invoice1.getpricePerItem () );
		
		System.out.printf ( "Total Invoice Amount: %s\n",
		invoice1.getinvoiceAmount () );
	} //end main method
}//end public class InvoiceTest

the output is showing this:


c:\SimplyJava\Invoice>java InvoiceTest
Original invoice information
Part Number: null
Part Description: null
Quantity: 5
Price Per Item: 14.99
Total Invoice Amount: 74.95

c:\SimplyJava\Invoice>

[maknib]

Well firstly don't make a new thread, you're other question (which is the same) is only 4 theads below and posted less than an hour ago!

be patient

Secondly with all the printF statements and methods and params and substitutions you should know about strings. if not you may need to read one of these

http://tinyurl.com/39xzz7u

[JosAH]

public class Invoice
{
	private String partNumber; // part number for invoice
	...
	// set Part number:
	public void setpartNumber ( String partNumber)
	{
		partNumber = partNumber; //accept the passed part value-assgn to  instance v partNumber
	}// end method setpartNumber

This is wrong (the same mistake occurs in the other setter methods); your parameter shadows your member variable (they have the same name) so all your method does is set the parameter to its own value; change your method(s) to this:

	public void setpartNumber ( String partNumber)
	{
		this.partNumber = partNumber;
	}

kind regards,

Jos

[Tolls]

Oh great.
I could have saved myself a post!
Why ask the question in the other thread and then go and post a new thread??

Bah!

[JosAH]

Oh great.
I could have saved myself a post!
Why ask the question in the other thread and then go and post a new thread??

Bah!

My fault; I should've noticed that this is the double post (but I didn't have my espression yet so I'm innocent ;-)

kind regards,

Jos

[Tolls]

You?
Innocent?

Hah!
;)

[JosAH]

You?
Innocent?

Hah!
;)

Yes, me; as a newborn baby. Except for the eggrolls and chocolate icecream incident or the painted balls in the dishwasher, but I didn't do that, honest.

kind regards,

Jos ;-)