Can anyone explain why my 3rd and 4th requirements are not met?

Question about the task

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package com.codegym.task.task18.task1828;

/*
Prices 2

*/

import java.io.*;
import java.util.*;

public class Solution {
    public static void main(String[] args) throws IOException {
        //The program should read a file name for CrUD operations from the console.
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String fileName = reader.readLine();
        reader.close();

        //setup a copy of the files data
        HashMap<String, String> map = new LinkedHashMap<>();
        FileInputStream fileInputStream = new FileInputStream(fileName);
        BufferedReader bufferedInputStream = new BufferedReader(new InputStreamReader(fileInputStream));
        while(bufferedInputStream.ready()) {
            String line = bufferedInputStream.readLine();
            String id = line.substring(0,8);
            String data = line.substring(8);
            map.put(id,data);
        }
        fileInputStream.close();
        bufferedInputStream.close();
        //When you run the program without arguments, the product list must remain unchanged.
        if(!args[0].isEmpty()){
            //When the program is started with the arguments "-u id productName price quantity", the product information in the file should be updated.
            if(args[0].equals("-u")){
                StringBuilder id = new StringBuilder(String.valueOf(args[1]));
                StringBuilder productName = new StringBuilder(args[2]);
                StringBuilder price = new StringBuilder(String.valueOf(Double.parseDouble(args[3])));
                StringBuilder quantity = new StringBuilder(String.valueOf(Integer.parseInt(args[4])));
                while (id.length() < 8) {
                    id.append(" ");
                }
                while (productName.length() < 30) {
                    productName.append(" ");
                }
                while (price.length() < 8) {
                    price.append(" ");
                }
                while (quantity.length() < 4) {
                    quantity.append(" ");
                }
                String updateData = productName.toString()+price.toString()+quantity.toString();
                //update value in file copy
                map.replace(String.valueOf(id), updateData);
                //update file with file copy
                writeToFile(fileName,map);
            }
            //When the program is started with the arguments "-d id", the line for the product with the specified id should be removed from the file.
            if(args[0].equals("-d")){
                StringBuilder id = new StringBuilder(String.valueOf(args[1]));
                while(id.length()<8) { id.append(" "); }
                map.remove(String.valueOf(id));
                //update file with file copy
                writeToFile(fileName,map);
            }
        }
    }
    public static void writeToFile(String fileName, HashMap<String, String> map) throws IOException {
        //update file with file copy
        Writer fileWriter = new FileWriter(fileName,false);
        for(String key : map.keySet()){
            fileWriter.write(key+ map.get(key));
        }
        fileWriter.close();
    }
}

CrUD for a table inside a file
Read a file name for CrUD operations from the console

The program runs with one of the following sets of arguments:
-u id productName price quantity
-d id

Argument values:
where id is 8 characters
productName is 30 characters
price is 8 characters
quantity is 4 characters
-u updates the data for the product with the specified id
-d performs the physical deletion of the product with the specified id (all data related to the passed id)

The file data is stored in the following order (without separating spaces):
id productName price quantity
Each data field is padded with spaces up to its length

Example:
19847 Swim trunks, blue 159.00 12 198479 Swim trunks, black with printe173.00 17 19847983Snowboard jacket with reflecti10173.991234

Requirements:

The program should read a file name for CrUD operations from the console.
When you run the program without arguments, the product list must remain unchanged.
When the program is started with the arguments "-u id productName price quantity", the product information in the file should be updated.
When the program is started with the arguments "-d id", the line for the product with the specified id should be removed from the file.
The file streams must be closed.

package com.codegym.task.task18.task1828; /* Prices 2 */ import java.io.*; import java.util.*; public class Solution { public static void main(String[] args) throws IOException { //The program should read a file name for CrUD operations from the console. BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName = reader.readLine(); reader.close(); //setup a copy of the files data HashMap<String, String> map = new LinkedHashMap<>(); FileInputStream fileInputStream = new FileInputStream(fileName); BufferedReader bufferedInputStream = new BufferedReader(new InputStreamReader(fileInputStream)); while(bufferedInputStream.ready()) { String line = bufferedInputStream.readLine(); String id = line.substring(0,8); String data = line.substring(8); map.put(id,data); } fileInputStream.close(); bufferedInputStream.close(); //When you run the program without arguments, the product list must remain unchanged. if(!args[0].isEmpty()){ //When the program is started with the arguments "-u id productName price quantity", the product information in the file should be updated. if(args[0].equals("-u")){ StringBuilder id = new StringBuilder(String.valueOf(args[1])); StringBuilder productName = new StringBuilder(args[2]); StringBuilder price = new StringBuilder(String.valueOf(Double.parseDouble(args[3]))); StringBuilder quantity = new StringBuilder(String.valueOf(Integer.parseInt(args[4]))); while (id.length() < 8) { id.append(" "); } while (productName.length() < 30) { productName.append(" "); } while (price.length() < 8) { price.append(" "); } while (quantity.length() < 4) { quantity.append(" "); } String updateData = productName.toString()+price.toString()+quantity.toString(); //update value in file copy map.replace(String.valueOf(id), updateData); //update file with file copy writeToFile(fileName,map); } //When the program is started with the arguments "-d id", the line for the product with the specified id should be removed from the file. if(args[0].equals("-d")){ StringBuilder id = new StringBuilder(String.valueOf(args[1])); while(id.length()<8) { id.append(" "); } map.remove(String.valueOf(id)); //update file with file copy writeToFile(fileName,map); } } } public static void writeToFile(String fileName, HashMap<String, String> map) throws IOException { //update file with file copy Writer fileWriter = new FileWriter(fileName,false); for(String key : map.keySet()){ fileWriter.write(key+ map.get(key)); } fileWriter.close(); } }

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dhanush

Level 30 , Chennai, India

30 September 2020, 17:42

solution

#1 You almost done everything look at the lines 36 and 37 don't convert them into Double or Integer, actually i was also doing the same mistake after reading others comments i changed that, if we convert them means may be it won't verify. #2 Once you changed that it verifies the 3rd requirement but not fulfilled there's a problem in the writeToFile method #2.1 Don't use for each loop to display the result use map iterator it will be handy because if you use for each loop means it won't get all the keys or values. #2.2 Write key + value to the file. #2.3 While writing to the file use next line currently your program doesn't leave any new lines it just update or delete and display the result in single line, if you again want's to delete a line or update means you'll get an exception.

public static void writeToFile(String fileName, HashMap<String, String> map) throws IOException {
       //update file with file copy
       Writer fileWriter = new FileWriter(fileName,false);
       for(String key : map.keySet()){ // change this line to map Entry
           fileWriter.write(key+ map.get(key)); // display the key and value and add new line at the end of the file
       }
       fileWriter.close();
   }

Lars Hoogma

Level 19 , Sneek, Netherlands

30 September 2020, 19:57

thanks for the help, so dumb of me to convert my data when it is not asked XD