Very unclear as to what is required

Question about the task

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I just have no clue what they want with the third requirement Edit: I tried changing line 40 to j=0, just in case the ID should be included in the displayed info; still failing the same condition Edit2: I changed lines 33-47 to:

HashMap<Integer, String> idAndInfo = new HashMap<>();
 ArrayList<Integer> ids = new ArrayList<>();

        //add all products to HashMap with Key = ID and Value = product info
        for (int i = 0; i<products.size(); i++){
            String[] info = products.get(i).split(" ");
            int id = Integer.parseInt(info[0]);
            ids.add(id);
            String productInfo = "";
            for (int j = 1; j<info.length-1;j++){
                s += (info[j] + " ");
            }
            s+= info[info.length-1];
            idAndInfo.put(id, productInfo);
        }

        for (int i = 0; i<ids.size(); i++)
        productSearch(idAndInfo, ids.get(i));

(again with and without the ID in the displayed info) - still not passing

Read a file name from the console.
Search the file for information related to the specified id. Display it in the format used in the file.
The program is started with one argument: id (an int).
Close the streams.

The file data is separated by spaces and stored in the following order:
id productName price quantity
where id is an int
productName is a String — it can contain spaces
price is a double
quantity is an int

The information for each product is stored on a separate line.

Requirements:

The program should read a file name from the console.
Create an input stream for the file.
The program should search the file and display information related to the specified id passed as the first argument.
The stream used to read the file must be closed.

package com.codegym.task.task18.task1822; /* Finding data inside a file */ import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.HashMap; public class Solution { public static void main(String[] args) throws Exception{ BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName = reader.readLine(); FileInputStream fileInputStream = new FileInputStream(fileName); BufferedReader fileReader = new BufferedReader(new InputStreamReader(fileInputStream)); //read all lines from file and add to ArrayList String s; ArrayList<String> products = new ArrayList<>(); while ((s=fileReader.readLine())!=null){ products.add(s); } reader.close(); fileInputStream.close(); fileReader.close(); HashMap<Integer, String> idAndInfo = new HashMap<>(); //add all products to HashMap with Key = ID and Value = product info for (int i = 0; i<products.size(); i++){ String[] info = products.get(i).split(" "); int id = Integer.parseInt(info[0]); String productInfo = ""; for (int j = 1; j<info.length-1;j++){ s += (info[j] + " "); } s+= info[info.length-1]; idAndInfo.put(id, productInfo); } productSearch(idAndInfo, 10); } //method for searching product info based on passed ID argument public static void productSearch(HashMap<Integer, String> hashMap, Integer id){ for (HashMap.Entry<Integer, String> pair : hashMap.entrySet()){ if (id.equals(pair.getKey())) System.out.println(pair.getValue()); } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

15 January 2020, 17:10

solution

The problem with this code is that you declare 'productInfo' on line 39, and then enter it into the HashMap on line 44. Between those two lines you use the variable 's' to build the product info and never actually change its value from line 39. Fix this and you should be good. A little tip, when you split a string you can specify the amount of values returned as the second argument to the split() method. Take this bit of code for an example:

String test = "id productName price quantity";
String[] split = test.split(" ", 2);
System.out.println(split[0]);
System.out.println(split[1]);

The output would be: id productName price quantity The benefit to your code here is that you wouldn't have to build the rest of the product information (lines 40-43)

Anthony Chalk

Level 30 , London, United Kingdom

15 January 2020, 20:46

Well that was silly of me Thanks so much

- FniJnn -

Level 33 , Paris, France

15 January 2020, 13:05

Third requirement says : "display information related to the specified id passed as the first argument". Where do you use the first argument (args[0) ?

Anthony Chalk

Level 30 , London, United Kingdom

15 January 2020, 13:59

I've changed my code to:

HashMap<Integer, String> idAndInfo = new HashMap<>();

 //add all products to HashMap with Key = ID and Value = product info
 for (int i = 0; i<products.size(); i++){
     String[] info = products.get(i).split(" ");
     int id = Integer.parseInt(info[0]);
     String productInfo = "";
     for (int j = 1; j<info.length-1;j++){
         s += (info[j] + " ");
     }
     s+= info[info.length-1];
     idAndInfo.put(id, productInfo);
 }

 productSearch(idAndInfo, Integer.parseInt(args[0]));

tried both including and excluding the ID from the displayed info, still doesn't verify