₦airaland Forum

Hi everyone,

I'm a newbie to programming trying to build some skills around Java. I encountered an exercise in Dietel's Java how to program book. It's requesting to make an invoice program for a hardware store with constructors, get and set methods, and also calculate the total of the purchase on the invoice with quantity * price.

I tried my way around it and come up with these two classes. I'm now stock at an error saying partQuantity: an instance of type int cannot be returned by a method 'Java.lang.String'

Please help me out with this, I really don't know what next to do.

Here are the two classes for the program.

public class NewInvoicevoice
{
private String partName;
private String partDescription;
private int partQuantity;
private int partPrice;

public NewInvoice
(
String name,
String itemDescription,
int itemQuantity,
int itemPrice
) // ENDS CONSTRUCTOR ARGUMENTS
{
partName = name;
partDescription = itemDescription;
partQuantity = itemQuantity;
partPrice = itemPrice;
}

public void setName( String name )
{
partName = name;
}

public void setDescription( String itemDescription )
{
partDescription = itemDescription;
}

public void setQuantity(int itemQuantity)
{
partQuantity = itemQuantity;
}
public void setPrice( int itemPrice )
{
partPrice = itemPrice;
}

public String getName()
{
System.out.println ("ENTER THE NAME OF THE COMPONENT: " );
return partName;
}

public String getDescription()
{
System.out.println ("ENTER THE DESCRIPTION OF THE COMPONENT: " );
return partDescription;
}

public String getQuantity()
{
System.out.println ("ENTER THE QUANTITY ORDERED: " );
return partQuantity;
}
public int getPrice()
{
System.out.println ("ENTER THE PRICE OF THE COMPONENT: " );
return partPrice;
}

public void displayMessage( String nameOfStore)
{
System.out.printf ( "Welcome to %s HRDWARE STORE.", nameOfStore);
System.out.println ( "\n" ) ;
}

public void displayTotal( int itemTotal )
{
System.out.printf ( "THE TOTAL COST OF ALL YOUR PURCHASE(S) IS: ", + itemTotal + "\n" );
}

}

And here is its Test class

import java.util.Scanner;


public class NewInvoiceTest {


public static void main(String[] args) {



Scanner invoiceNm = new Scanner( System.in );
Scanner invoiceDsct = new Scanner( System.in );
Scanner invoiceQtty = new Scanner( System.in );
Scanner invoicePrc = new Scanner( System.in );
Scanner storeNm = new Scanner( System.in );


String invoiceName = invoiceNm.nextLine();
String invoiceDescription = invoiceDsct.nextLine();
int invoiceQuantity = invoiceQtty.nextInt();
int invoicePrice = invoicePrc.nextInt();
String storeNme = storeNm .nextLine();

String storeName = "DengrDEV";
int totalPurchase = invoicePrice * invoiceQuantity;

NewInvoice newInvoicea = new NewInvoice(invoiceName, invoiceDescription, invoiceQuantity, invoicePrice);

newInvoicea.displayMessage ( storeNme );
System.out.println ("" + newInvoicea.getName() + "\n" + newInvoicea.getDescription() + "\n" + newInvoicea.getQuantity() + "\n" + newInvoicea.getPrice() + "\n" + "" );
newInvoicea.displayTotal ( totalPurchase );

}

}

Thanks in anticipation.

halmat:
Hi everyone,
public class NewInvoicevoice
{
private String partName;
private String partDescription;
private int partQuantity;
private int partPrice;

public NewInvoice
(
String name,
String itemDescription,
int itemQuantity,
int itemPrice
) // ENDS CONSTRUCTOR ARGUMENTS

First of all, your class and constructor name must be the same. Your class name is NewInvoicevoice and the constructor is NewInvoice(). So rename the class to NewInvoice()

halmat:
Hi everyone,
public String getQuantity()
{
System.out.println ("ENTER THE QUANTITY ORDERED: " );
return partQuantity;
}

Secondly, the getQuantity() method has a return type of String, however you are returning partQuantity which has a datatype of int. So to fix this, replace "return partQuantity" with "return String.valueOf(partQuantity)"

1. Your constructor name and class names have to match

2. Why are you using constructors to set instance variables and still using set method again?? They playing the same roles in a way...

3. Your partQuantity is supposed to return an int type but you put the return type as String. Change the String to int. This exact one is what is causing the error

Goodluck

yungcheda:
1. Your constructor name and class names have to match

2. Why are you using constructors to set instance variables and still using set method again?? They playing the same roles in a way...

3. Your partQuantity is supposed to return an int type but you put the return type as String. Change the String to int. This exact one is what is causing the error

Goodluck

Osheyyyy baddest...

Thank you all, I really appreciate your efforts. I now got the compiler error out. Although the program is yet to function as I wish, I'm currently battling with it and will post the final code that receive input and print the entered value back to the user.

use quick fix

Thanks everyone, and here is my final code:

public class NewInvoice
{
private String partName;
private String partDescription;
private double partQuantity;
private double partPrice;


public void setName( String name )
{
partName = name;
}

public void setDescription( String itemDescription )
{
partDescription = itemDescription;
}

public void setQuantity(double itemQuantity)
{
partQuantity = itemQuantity;
}
public void setPrice( double itemPrice )
{
partPrice = itemPrice;
}

public String getName()
{
return partName;
}

public String getDescription()
{
return partDescription;
}

public double getQuantity()
{
return (partQuantity);
}
public double getPrice()
{
return partPrice;
}

public void displayMessage( String nameOfStore)
{
System.out.print("\n\n*************************************************" );
System.out.printf ( "\nWELCOME TO %s HARDWARE STORE.", nameOfStore);
System.out.println ( "\n" );
}

public void displayTotal( double itemTotal)
{
System.out.println( "" );
System.out.printf ( "THE TOTAL COST OF ALL YOUR PURCHASE(S) IS: \n$%.2f", itemTotal );
}

}

And its Test class

import java.util.Scanner;


public class NewInvoiceTest {


public static void main(String[] args) {



Scanner invoiceNm = new Scanner( System.in );
Scanner invoiceDsct = new Scanner( System.in );
Scanner invoiceQtty = new Scanner( System.in );
Scanner invoicePrc = new Scanner( System.in );
Scanner storeNm = new Scanner( System.in );

System.out.print( "Enter the store name: \n" );
String storeNme = storeNm .nextLine();

System.out.print( "Enter the item Name: \n" );
String invoiceName = invoiceNm.nextLine();

System.out.print( "Enter the item Description: \n" );
String invoiceDescription = invoiceDsct.nextLine();

System.out.print( "Enter the item Quantity: \n" );
double invoiceQuantity = invoiceQtty.nextDouble();

System.out.print( "Enter the item price ($): \n" );
double invoicePrice = invoicePrc.nextDouble();







NewInvoice newInvoicea = new NewInvoice();


newInvoicea.setName( invoiceName );



newInvoicea.setDescription( invoiceDescription );


newInvoicea.setQuantity( invoiceQuantity );


newInvoicea.setPrice( invoicePrice );

newInvoicea.displayMessage ( storeNme );

System.out.println ("NAME OF THE COMPONENT: \n" + newInvoicea.getName() +
"\n\nTHE DESCRIPTION OF THE COMPONENT: \n" + newInvoicea.getDescription() +
"\n\nQUANTITY ORDERED: \n" + newInvoicea.getQuantity() +
"\n\nPRICE OF THE COMPONENT: \n$" + newInvoicea.getPrice() + "" );
double invoiceTotal = newInvoicea.getQuantity() * newInvoicea.getPrice( );
newInvoicea.displayTotal( invoiceTotal );



}


}

Congratulations

halmat:
Thanks everyone, and here is my final code:

And its Test class

FincoApps:
Congratulations

Please elaborate more on quick fix

FincoApps:
Congratulations

Thanks sir.

FincoApps:
Congratulations

Thanks sir

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