Thread: Starting Out With Java Programming Challenge Chapter 10 #11

public static double getWeeklySales(String str)
{
double weekTotal = 0.0;

// Create the tokenizer.
StringTokenizer strtok = new StringTokenizer(str, ",");
// Accumulate the value of the tokens.
while (strtok.hasMoreTokens())
{
weekTotal =+ Double.parseDouble(str);
}

return weekTotal;
}

}
Exception in thread "main" java.lang.NumberFormatException: For input string: "1245.67,1490.07,1679.87,2371.46,1783.92,1461.99,2 059.77"
at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1241)
at java.lang.Double.parseDouble(Double.java:540)
at SalesAnalysis.getWeeklySales(SalesAnalysis.java:10 9)
at SalesAnalysis.main(SalesAnalysis.java:61)

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Originally Posted by Norm

The code at line 109 used an invalid String in the call to the parseDouble() method. Check the code to see what String should be used.

public static double getWeeklySales(String str)
{
double weekTotal = 0.0;

// Create the tokenizer.
StringTokenizer strtok = new StringTokenizer(str, ",");
// Accumulate the value of the tokens.
while (strtok.hasMoreTokens())
{
weekTotal =+ Double.parseDouble(str);
}

return weekTotal;
}
the error I am getting is with the "Double.parseDouble(str)"

public class SalesAnalysis
{
 
   public static void main(String[] args) throws IOException
   {
      // To hold a line from the file
       String line;
      // Accumulator for all weeks
       double totalWeeks = 0;
      // Average weekly sales
       double weeklyAverage ;
      // Total sales for a week
       double weeklyTotal =0;
      // Highest sales
       double highestSales;
      // Lowest sales
       double lowestSales;
      // Week # with highest sales
       int highWeek =0;
      // Week # with lowest sales
       int lowWeek=0;
      // The week number;
       int weekNumber = 0;          
      // Create a DecimalFormat object to format dollar amounts.
      DecimalFormat dollar = new DecimalFormat("$#,##0.00");
 
      // Open the SalesData.txt file.
      File file = new File("SalesData.txt");
      Scanner inputFile = new Scanner(file);
 
      // Process the file contents.
      while (inputFile.hasNext())
      {
           // Read a line from the file.
          line = inputFile.nextLine();
          // Increment the week counter.
          weekNumber ++;
          // Get the total sales for this week.
          getWeeklySales(line);
 
          weeklyTotal= getWeeklySales(line);
 
           // Calculate the average weekly sales.
            weeklyAverage = weeklyTotal/line.length();
           // Display the total and average for the week. 
          System.out.println("Week #" + weekNumber + " sales: " + weeklyTotal+
         "    Average daily sales for Week #" + weekNumber+": " + weeklyAverage);
      }
     // Accumulate the weekly sales.
      for (int i=0; i<=weekNumber;i++)
      {
      totalWeeks +=weeklyTotal; 
    // Find the highest and lowest so far.
      if (totalWeeks > weeklyTotal)
      highWeek = weekNumber;
      else
      lowWeek = weekNumber;
      }
      // Close the file
       inputFile.close();
 
   // Display the remaining results.
    System.out.println("Total sales for all weeks: " + totalWeeks +"\n"+ 
    "Average weekly sales: "+ totalWeeks/3 + "\n"+ "The highest sales were "
    + "during week #"+ highWeek+"\n"+"The lowest sales were made during week #"
    + lowWeek);
 
     }
 
   /**
      The getWeeklySales method accepts a string containing a
      list of sales for the week, with each day's sales 
      separated by commas. It tokenizes the string, totals
      the numbers, and returns the total sales for the week.
      @param str The string containing the list of sales.
      @return The total of the sales.
   */
 
   public static double getWeeklySales(String str)
   {
      double weekTotal = 0.0;
 
      // Create the tokenizer.
      StringTokenizer strtok = new StringTokenizer(str, ",");
     // Accumulate the value of the tokens.
 
         while (strtok.hasMoreTokens())
      {
          weekTotal =+ Double.parseDouble(strtok.nextToken());
      }
 
      return weekTotal;
   }
 
}

Current output:
Week #1 sales: 2059.77 Average daily sales for Week #1: 37.45036363636363
Week #2 sales: 1469.36 Average daily sales for Week #2: 26.71563636363636
Week #3 sales: 1128.36 Average daily sales for Week #3: 20.51563636363636
Total sales for all weeks: 4513.44
Average weekly sales: 1504.4799999999998
The highest sales were during week #3
The lowest sales were made during week #3
Expected output:
Week #1 sales:12,092.75 Average daily sales for week #1: $1,727.54
Week #2 sales:27,461.00 Average daily sales for week #2: $3,923.00
Week #3 sales:12,058.34 Average daily sales for week #3: $1,722.62
Total sales for weeks: $51,612.09
Average weekly sales: $17,204.03
The highest sales were made during week #2.
The lowest sales were made during week #3.

Originally Posted by Norm

Where is the debug println()s output that shows what values were read and used in computing the total?

I tried implementing this code in the while loop of the "getWeekly Sales" method and a run time exception was thrown:

System.out.println(strtok.nextToken());

Ok I reentered this code in the first while loop and realized that the code is skipping the first two lines in the .txt file that I am receiving the data from but I don't understand why it is skipping

  StringTokenizer strtok = new StringTokenizer(line, ",");
     // Accumulate the value of the tokens.
 
         while (strtok.hasMoreTokens())
         {
             System.out.println(strtok.nextToken());
         }

after looking at my code 3 time I realized how stupid I am I use the "=+" operator instead of "+=" that is why it wasn't accumulating correctly.