Question

Possible Duplicate:
How do I compare strings in Java?
String Comparison in Java…?

I’m working on what I though was a very simple problem…
Basic 101 shopping cart with product list hard coded (practice question only – I understand this is not how it would really be done)

I want the user to enter a string – a product code and then get the description of the associated product back from the Description method

It is returning a 0 value i.e. the if statements in the methods don’t seem to recognise the user entered String.

The hard coded strings work – the keyboard entered string does not
I am stumped but I think I’m just missing something fundamental

import java.util.*;

class CW1ShoppingCart1_2ShowProdAndGetChoice
{
public static void main(String[] args)

{
/*PART 1 Offer catalogue and get user choice*/

System.out.println("ITEMS AVAIALBLE TODAY: \n");
System.out.print("P4383"+ "\t"+ CW1ShoppingCart1GetProductDetails.Description("P4383"));
System.out.println("\t"+ "$"+ CW1ShoppingCart1GetProductDetails.Price("P4383"));
System.out.print("P4385"+ "\t"+ CW1ShoppingCart1GetProductDetails.Description("P4385"));
System.out.println("\t"+ "$"+ CW1ShoppingCart1GetProductDetails.Price("P4385"));
System.out.print("P4387"+ "\t"+ CW1ShoppingCart1GetProductDetails.Description("P4387"));
System.out.println("\t"+ "$"+ CW1ShoppingCart1GetProductDetails.Price("P4387"));
System.out.println("\nTO START SHOPPING ENTER A PRODUCT CODE AND HIT RETURN \n");

Scanner in = new Scanner (System.in);
String ProdCode =in.nextLine();

System.out.println("You Chose: "+ CW1ShoppingCart1GetProductDetails.Description(ProdCode));

}
}

class CW1ShoppingCart1GetProductDetails
{

static String Description(String ProdCode)
{

String Proddesc;

if(ProdCode=="P4387")Proddesc = "Little used helper monkey - 1 ";
else if(ProdCode=="P4385") Proddesc = "Chilli chocolate - 100g ";
else if(ProdCode=="P4383")  Proddesc = "State-owned Bank - real value - 1 entity ";
else Proddesc = "0";

return Proddesc;
}

static double Price(String ProdCode)
{

double ProdPrice;

if(ProdCode=="P4387")  ProdPrice = 1200;
else if(ProdCode=="P4385") ProdPrice = 3.27;
else if(ProdCode=="P4383")  ProdPrice = -0.08;
else ProdPrice = 0;

return ProdPrice;
}

} 

Answer 1

The problem is that you are using == to compare strings. Use equals instead.

if(ProdCode.equals("P4387"))Proddesc = "Little used helper monkey - 1 ";

and so on