Please help

Question about the task

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Really unsure why all those conditions are failing Edit: I've moved lines 44/45 and 49/50 out of the loops. Still failing

Make the joinData method transactional, i.e. if it fails, then the data must not be changed.
1. Read 2 file names from the console.
2. Read from the files line by line. Read from the first file into allLines, from the second file — into linesForRemoval.
In the joinData method:
3. If the allLines list contains all the lines from linesForRemoval, then remove from the allLines list all the lines that are in linesForRemoval.
4. If the condition in Item 3 is not satisfied, then:
4.1. clear the data in allLines
4.2. throw a CorruptedDataException
The joinData method should be called in main. Handle all exceptions in the main method.
Don't forget to close the streams.

Requirements:

The Solution class must contain a public static List<String> field called allLines.
The Solution class must contain a public static List<String> field called linesForRemoval.
The Solution class must have a public void joinData() method that can throw a CorruptedDataException.
The program should read the names of two files from the console.
The program must read line by line from the first file into the allLines list.
The program must read line by line from the second file into the linesForRemoval list.
The joinData method must remove from the allLines list all lines in the linesForRemoval list if allLines contains all the lines in the linesForRemoval list.
The joinData method must clear the allLines list and throw a CorruptedDataException, if allLines does not contain all the lines in the linesForRemoval list.
The joinData method should be called in main.

package com.codegym.task.task17.task1721; import java.io.BufferedReader; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List; /* Transactionality */ public class Solution { public static List<String> allLines = new ArrayList<>(); public static List<String> linesForRemoval = new ArrayList<>(); public static void main(String[] args) { Solution solution = new Solution(); try { solution.joinData(); } catch (IOException e) { e.printStackTrace(); } } public void joinData() throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName1 = reader.readLine(); String fileName2 = reader.readLine(); FileInputStream fileInputStream1 = new FileInputStream(fileName1); FileInputStream fileInputStream2 = new FileInputStream(fileName2); BufferedReader fileReader1 = new BufferedReader(new InputStreamReader(fileInputStream1)); BufferedReader fileReader2 = new BufferedReader(new InputStreamReader(fileInputStream2)); String s; while ((s = fileReader1.readLine())!=null) { allLines.add(s); fileInputStream1.close(); fileReader1.close(); } while ((s = fileReader2.readLine())!=null) { linesForRemoval.add(s); fileInputStream2.close(); fileReader2.close(); } reader.close(); int count = 0; for (int i =0; i<linesForRemoval.size(); i++){ if (allLines.contains(linesForRemoval.get(i))) count++; } if (count == linesForRemoval.size()){ for (int i = 0; i<allLines.size(); i++){ for (int j =0; j<linesForRemoval.size(); j++){ if (allLines.get(i).equals(linesForRemoval.get(j))){ allLines.remove(i); i--; } } } } else { allLines.clear(); throw new CorruptedDataException(); } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

6 January 2020, 14:17

The big problem is that the reading loops are not working properly. This is because the stream is closed each loop cycle. Past the first cycle of the loop, reading from a closed stream will not work and will throw "java.io.IOException: Stream closed". Both loops should look like this:

while ((s = fileReader1.readLine())!=null) {
   allLines.add(s);
}
fileInputStream1.close();
fileReader1.close();

Anthony Chalk

Level 30 , London, United Kingdom

6 January 2020, 14:59

I changed it but it's still failing the same conditions

Guadalupe Gagnon

Level 37 , Tampa, United States

6 January 2020, 16:19

did you change both loops?

Guadalupe Gagnon

Level 37 , Tampa, United States

6 January 2020, 16:25

solution

Try moving lines 30-52 to the main method:

public static void main(String[] args) {
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
            String fileName1 = reader.readLine();
            String fileName2 = reader.readLine();
            reader.close();

            BufferedReader fileReader1 = new BufferedReader(new FileReader(fileName1));
            BufferedReader fileReader2 = new BufferedReader(new FileReader(fileName2));

            String s;
            while ((s = fileReader1.readLine()) != null) {
                allLines.add(s);
            }
            fileReader1.close();

            while ((s = fileReader2.readLine()) != null) {
                linesForRemoval.add(s);
            }
            fileReader2.close();
            Solution solution = new Solution();
            solution.joinData();
        }catch (Exception ignored){}
    }

Anthony Chalk

Level 30 , London, United Kingdom

6 January 2020, 16:46

Thank so much; that did the trick. Was what I did actually wrong or just CodeGym being pedantic?

Guadalupe Gagnon

Level 37 , Tampa, United States

6 January 2020, 17:03

It depends on what you mean by wrong. The instructions could be a lot more clear. The first sentence: "Make the joinData method transactional, i.e. if it fails, then the data must not be changed." should be after step 1 and 2. Of they should specifically say that those 2 steps should be in the main method. The instructions drove me up a wall when I originally went through all the levels because you don't know if you were misinterpreting things or the task was legitimately bugged. **They have pretty much fixed the bugs at this point.**

KIN SOCHEAT

Level 34 , Phnom Penh, Cambogia

4 January 2020, 02:24

if(allLines.containsAll(linesForRemoval)){ // linesForRemoval.removeAll(allLines); allLines.removeAll(linesForRemoval); } else{ allLines.clear(); throw new CorruptedDataException(); }

Anthony Chalk

Level 30 , London, United Kingdom

4 January 2020, 12:08

Thanks, that makes it much more concise. It's still failing the same conditions though