PrintWriter creates file but doesn't print to file - java

This is a college course assignment that consists of classes TotalSales and TotalSalesTest.In the main program I have created a two dimensional array to output a columnar layout with cross-totals in 4 rows and 5 columns. This program outputs sales totals by row for each sales person(1 - 4) and output by column for products(1 - 5). I have created extra elements in the array to store total for rows and columns. So far both classes compiles. The problem is that although the PrintWriter creates a notepad file, it doesn't print to it. I could use some help on this problem. Here is the code`
//write program in a two diminsional array to output a columnar layout with cross-totals in 4 rows and 5 columns
//program outputs sales totals by row for each sales person(1 - 4) and output by column for products(1 - 5)
//create extra elements to store total for rows and columns
import java.util.Scanner;
import java.io.*;
public class TotalSales
{
private int salesPerson; //declare class variable
private int productNumber;//declare class variable
private double totalSales;//declare class variable
private double allSales;
//declare input and output variables
Scanner inFile; //declare inFile variable
PrintWriter outFile;//declare outFile variable
double[][]sales = new double[6][7];//declare array sales
public void initializer()
{
try
{
inFile = new Scanner( new File( "assign06.txt" ) );
outFile = new PrintWriter( "MonthlyTotalSales.txt" );
outFile.flush();
}
catch (FileNotFoundException e)
{
System.out.println("The input file could not be found!");
System.exit(1);
}
while(inFile.hasNext()) //while there is data to process…
{
salesPerson = inFile.nextInt();//reads salesPerson
productNumber = inFile.nextInt();//reads productNumber
totalSales = inFile.nextDouble();//reads totalSales
sales[salesPerson][productNumber]+=totalSales;
sales[salesPerson][6]+=totalSales;
sales[5][productNumber]+=totalSales;
allSales += totalSales;
} //end while loop
printDetails(sales);//call method printDetails
finishUp();//call method finishUp
}//end initializer
public void printDetails(double[][] array)
{
outFile.println("\t1\t2\t3\t4\t5");
for (int salesPerson =1; salesPerson <5; salesPerson++)
{
outFile.print(salesPerson+ " ");
for(int productNumber=1; productNumber <=array.length; productNumber++)
outFile.print(array[salesPerson][productNumber]+" ");
//end inside loop
outFile.println();
}//end outside loop
outFile.print("Total: \t ");
for(int salesTotal=1; salesTotal<array.length; salesTotal++)
{
outFile.print(array[5][salesTotal] +" ");
}
outFile.print(allSales);
outFile.println();
outFile.print(" ");
outFile.println();
}//end printDetails
public void finishUp()
{
inFile.close();
outFile.close();
System.out.println("The program has finished.");
}//end finishUp
}//end class TotalSales
Here is the test program:
public class TotalSalesTest
{
public static void main(String[] args)
{
TotalSales ts = new TotalSales();
ts.initializer();
}//end method main
}
Here is the text file for the input:
1 1 37.50
1 2 77.00
1 3 68.75
1 4 61.25
1 5 175.00
2 1 45.00
2 2 66.00
2 3 27.50
2 4 49.00
2 5 250.00
3 1 67.50
3 2 33.00
3 4 73.50
3 5 200.00
4 1 15.00
4 2 99.00
4 3 123.75
4 4 85.75
4 5 125.00
1 1 60.00
1 2 88.00
1 3 41.25
1 4 49.00
1 5 225.00
2 1 67.50
2 2 33.00
2 3 27.50
2 4 122.50
2 5 25.00
3 1 60.00
3 2 44.00
3 3 96.25
3 4 36.75
3 5 50.00
4 1 75.00
4 2 11.00
4 3 41.25
4 4 98.00
4 5 125.00
1 1 45.00
1 2 33.00
1 3 27.50
1 4 61.25
1 5 200.00
2 1 52.50
2 2 22.00
2 3 13.75
2 4 36.75
2 5 50.00
3 1 37.50
3 2 88.00
3 3 96.25
3 4 36.75
4 1 37.50
4 2 77.00
4 3 82.50
4 4 73.50
4 5 25.00
1 1 30.00
1 2 88.00
1 3 41.25
1 4 12.25
1 5 175.00
2 1 45.00
2 2 22.00
2 3 68.75
2 4 98.00
3 2 88.00
3 3 41.25
3 4 24.50
4 1 30.00
4 2 88.00
4 3 82.50
4 4 122.50
4 5 175.00


You call printDetails before initializing the writer... Move the printDetails call after outFile = new PrintWriter( "MonthlyTotalSales.txt" );and it should be fine. However, you should have included your constructor since as it is right now, I would think your code throws a NullPointerException because the writer is never initialized. You also need to close the file before writing in it, or at least you need to flush.
The whole structure of your code is bad, you should never have a method such as mainProgram on a class, you should never use a file as an attribute just to use it in every method, and you should never separate in different methods creation and closing of i/o classes.


It seems you didn't call outFile.close();
Call your finishUp() method once you complete writing in the file.


I think your program crashes with a nullpointer on
inFile.hasNext()
because you never actually opened or even instantiated the input file along with the output file in the try/catch block. Whoops!
change
try
{
outFile = new PrintWriter( "MonthlyTotalSales.txt" );
}
to
try
{
inFile = new Scanner(new File("Input.txt"));
outFile = new PrintWriter( "MonthlyTotalSales.txt" );
}

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Basically you have two threads that modify the same variable x. There is no garantee about the order of execution.
You should synchronize.
With your current implementation you may face a problem (The race condition problem): Race condition example
Something like this is an scenario that most likely is going to happen to you:
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Thank You
edit: Here is the contents of the tables:
TABLE1:
ROW COLUMN+CELL
0 column=gpnum:, timestamp=1481300288449, value=def123
0 column=mpnum:, timestamp=1481300273355, value=abc123
0 column=price:, timestamp=1481300255337, value=85.0
1 column=gpnum:, timestamp=1481301599999, value=def2244
1 column=mpnum:, timestamp=1481301582336, value=011511607
1 column=price:, timestamp=1481301673886, value=0.76
TABLE2
ROW COLUMN+CELL
0 column=brand:, timestamp=1481300227283, value=x
0 column=mpnum:, timestamp=1481300212289, value=abc123
0 column=price:, timestamp=1481300110950, value=50.0
1 column=mpnum:, timestamp=1481301806687, value=011511607
1 column=price:, timestamp=1481301777345, value=1.81
13 column=webtype:, timestamp=1483507543878, value=US
3 column=avail:, timestamp=1481306538360, value=avail
3 column=brand:, timestamp=1481306538360, value=brand
3 column=descr:, timestamp=1481306538360, value=description
3 column=dist:, timestamp=1481306538360, value=distributor
3 column=mpnum:, timestamp=1481306538360, value=pnum
3 column=price:, timestamp=1481306538360, value=price
3 column=url:, timestamp=1481306538360, value=url
3 column=webtype:, timestamp=1481306538360, value=webtype
4 column=avail:, timestamp=1481306538374, value=4
4 column=brand:, timestamp=1481306538374, value=x
4 column=descr:, timestamp=1481306538374, value=description
4 column=dist:, timestamp=1481306538374, value=x
4 column=mpnum:, timestamp=1482117383212, value=011511607
4 column=price:, timestamp=1481306538374, value=34.51
4 column=url:, timestamp=1481306538374, value=x
4 column=webtype:, timestamp=1481306538374, value=US
5 column=avail:, timestamp=1481306538378, value=
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THIRD TABLE (to store result matches)
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0 column=gpnum:, timestamp=1481301813849, value=def2244
0 column=gprice:, timestamp=1481301813849, value=0.76
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Here is how I got it to print like described:
Random rn = new Random();
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