Need help getting data from a text file in java. I need to find the maximum price and the data associated with the price

Question

write a program(AvocadoMining.java) that has the following several fields and three methods

     size:int, the number of lines in a file.

     prices: double[]

     totalVolumes:double[]

     regions: String[]

   + AvocadoMining(fileName:String)

It reads the file, assigns the number of lines in the file to the field size, then creates several arrays for prices, totalVolumes, regions.

    +findMax():void

   The method finds out the maximum average price during the year, and then prints the price, the total volumes and the region associated with the price.

      +findTotal(String regionName):double

    The method finds out and returns the total of the total volumes for a given region during  the year.

I am working on the findMax() method but i am having trouble getting all of the data in my code. Here is my work so far

    import java.util.Scanner;
    import java.io.*;
    public class AvocadoMining
    {
       private int size=0;
       private String[] region;
       private double[] price;
       private double[] totalVolumes;




   public AvacadoMining(String fileName) throws IOException
   {   
     File file=new File(fileName);
     Scanner inputF = new Scanner(file);
  
     while(inputF.hasNextLine())
     {
      String str=inputF.nextLine();
      size++;
  
     }

  
     inputF=new Scanner(file);
     region = new String[size];
     price = new double[size];
     totalVolumes=new double[size];
     int index=0;
     while(inputF.hasNextLine())
     {
       String[] tokens = inputF.nextLine().split(",");
       price[index]=Double.parseDouble(tokens[2]);
       totalVolumes[index]=Double.parseDouble(tokens[3]);
       region[index]=tokens[13].trim();
       index++;
     
  
     } 
  
   }   
  
     public void findMax() throws IOException
     {
       double maximum = price[0];
       for(int i=0;i<price.length;i++)
       {
         if(maximum<price[i])
           maximum = price[i];
        
       }
     
     
     
       String line ="Price: $.2f"+maximum + " Total Volume: "+ 
       totalVolumes[price.indexOf(maximum)] +"Region: " + 
       region[price.indexOf(maximum)]; 
  
  
  }

}

If I try to compile I will get a cannot find symbol error for price in the String line.

Answer 1

indexOf is not a method on arrays. You'd have to write it yourself. In real life coding (for dollars or eyeballs), you don't use arrays, you'd use Lists which do have an indexOf function, but this sounds like homework, so you're probably 'locked' into arrays. You can write indexOf yourself, with a for loop.

Answer 2

Change your indexOf line as shown below,

String line = "Price: $.2f" + maximum + " Total Volume: " + totalVolumes[indexOf(price, maximum)] + "Region: " + region[indexOf(price, maximum)];

After that, add the below method,

public int indexOf(double arr[], double t) 
{ 
    int len = arr.length; 
    return IntStream.range(0, len) 
        .filter(i -> t == arr[i]) 
        .findFirst() // first occurrence 
        .orElse(-1); // No element found 
}