Printf formatting error incompatible types

Question

I keep getting this error saying incompatible types: java.io.PrintStream cannot be converted to java.lang.String and I don't get how to get it to work for my toString Method. I've tried assigning it to a variable and then returning it, and then just plan printing it out as a return statement, I don't see anything wrong with my printf formatting. Help is appreciated.

 import java.text.NumberFormat;

    public class Item
    {
        private String name;
        private double price;
        private int quantity;


        // -------------------------------------------------------
        //  Create a new item with the given attributes.
        // -------------------------------------------------------
        public Item (String itemName, double itemPrice, int numPurchased)
        {
        name = itemName;
        price = itemPrice;
        quantity = numPurchased;
        }


        // -------------------------------------------------------
        //   Return a string with the information about the item
        // -------------------------------------------------------
        public String toString ()
        {

        return System.out.printf("%-15s $%-8.2f %-11d $%-8.2f", name, price, 
     quantity, price*quantity);
        }

        // -------------------------------------------------
        //   Returns the unit price of the item
        // -------------------------------------------------
        public double getPrice()
        {
        return price;
        }

        // -------------------------------------------------
        //   Returns the name of the item
        // -------------------------------------------------
        public String getName()
        {
        return name;
        }

        // -------------------------------------------------
        //   Returns the quantity of the item
        // -------------------------------------------------
        public int getQuantity()
        {
        return quantity;
        }
    }

You are trying to print a double as a float, use d for doubles, f for floats — Ferrybig
– Ferrybig, Commented Apr 25, 2017 at 8:00

Suresh Atta · Accepted Answer · 2017-04-25 08:00:44Z

1

 return System.out.printf("%-15s $%-8.2f %-11d $%-8.2f", name, price, 
     quantity, price*quantity);

You are trying to return PrintStream. That is not correct caause the toString should return a String.

You should have used String#format method, which gives back a String after fomratting

return String.format("%-15s $%-8.2f %-11d $%-8.2f", name, price, 
         quantity, price*quantity);

answered Apr 25, 2017 at 8:00

Suresh Atta

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Comments

BackSlash · Accepted Answer · 2017-04-25 08:00:40Z

1

System.out.printf does not return a string, You are looking for String.format

public String toString () {
    return String.format("%-15s $%-8.2f %-11d $%-8.2f", name, price, quantity, price*quantity);
}

answered Apr 25, 2017 at 8:00

BackSlash

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Comments

Jens · Accepted Answer · 2017-04-25 08:00:55Z

1

Change

 System.out.printf("%-15s $%-8.2f %-11d $%-8.2f", name, price, 
 quantity, price*quantity);

to

 String.format("%-15s $%-8.2f %-11d $%-8.2f", name, price, 
 quantity, price*quantity);

Because System.out.println() if for printing a string to console. Not to create a formated string-

answered Apr 25, 2017 at 8:00

Jens

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Comments

Dawood ibn Kareem · Accepted Answer · 2017-04-25 08:07:42Z

1

The error is caused by

return System.out.printf(....)

If you really want to return a String from this method then try

return String.format(....);

edited Apr 25, 2017 at 8:07

Dawood ibn Kareem

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answered Apr 25, 2017 at 8:00

Scary Wombat

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2 Comments

Scary Wombat Over a year ago

@dawood-ibn-kareem Thanks for the edit. Did you get married and change your name?

Dawood ibn Kareem Over a year ago

Not recently. Just my handle here.

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