LinkedHashMap from CSV not getting all entries

Question

CSV file into variable in order. I've been trying to read a CSV file which contains two columns, a title and then a list of entries.

Currently I've been using a LinkedHashMap; using the following loop to read, split and create the LinkedHashMap.

However it currently gets stuck on line 5 of my CSV. Here's the current read loop:

public static LinkedHashMap<String, ArrayList<String>> runningOrderMap(String filename) throws IOException {
        LinkedHashMap<String, ArrayList<String>> linkedHashMap = new LinkedHashMap<>(50);
        String currentLine = ""; //init iterator variable
        String[] valuesTMP;
        try {
            bufferedReader = new BufferedReader(new FileReader(filename));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        while((currentLine = bufferedReader.readLine()) != null){
            valuesTMP = currentLine.split(", ");
            ArrayList<String> values = new ArrayList<>();
            String key = valuesTMP[0].split("\t")[0].trim();
            values.add(valuesTMP[0].split("\t")[1].trim());
            for(int i = 1; i < valuesTMP.length; i++){
                values.add(valuesTMP[i]);
                System.out.println(valuesTMP[i]);
                linkedHashMap.put(key, values);
            }
        }
        System.out.println("linked hashmap:"+linkedHashMap.keySet().size());
        return linkedHashMap;
    }

the example data is formatted as such, title which varies in length, a tab, then a list of content entries like that:

title   content, content2

title example    content, content2, content3

title example three   content, content2

title example    content, content2

and this data goes on for about 20 lines, however the LinkedHashMap will not go past line 5:

title example two   content

I need to preserve the line order in the array.

the 2nd and 4th entries in your example have the same key `title example` - so the second one will override the first one in the map. — assylias, Dec 12 '18 at 17:48
The real data set only has keys which are different, I can't post the real data so I used this instead — Isaac Manzi, Dec 12 '18 at 17:50
Nothing jumps out in your code. It's possible to reproduce the behaviour with your example but you say it doesn't reflect your actual data so it's hard to help you much more. I suggest you create a [mcve]. — assylias, Dec 12 '18 at 17:55
What do you see if you add `System.out.println( key );` just above `linkedHashMap.put(key, values);` ? — David Soroko, Dec 12 '18 at 18:13
the correct key, is outputted, I'm not sure why it only deos 5 of them — Isaac Manzi, Dec 12 '18 at 18:15

score 2 · Accepted Answer · answered Dec 12 '18 at 18:32

It seems I know what is wrong)

Try to move line linkedHashMap.put(key, values); out of internal for loop, like this:

public static LinkedHashMap<String, ArrayList<String>> runningOrderMap(String filename) throws IOException {
    LinkedHashMap<String, ArrayList<String>> linkedHashMap = new LinkedHashMap<>(50);
    String currentLine = ""; //init iterator variable
    String[] valuesTMP;
    try {
        bufferedReader = new BufferedReader(new FileReader(filename));
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    while((currentLine = bufferedReader.readLine()) != null){
        valuesTMP = currentLine.split(", ");
        ArrayList<String> values = new ArrayList<>();
        String key = valuesTMP[0].split("\t")[0].trim();
        values.add(valuesTMP[0].split("\t")[1].trim());
        for(int i = 1; i < valuesTMP.length; i++){
            values.add(valuesTMP[i]);
            System.out.println(valuesTMP[i]);
        }
        linkedHashMap.put(key, values); // <--this line was moved out from internal for loop
    }
    System.out.println("linked hashmap:"+linkedHashMap.keySet().size());
    return linkedHashMap;
}

Because, you see, this internal for loop is executed only if there are more than one parts of content

LinkedHashMap from CSV not getting all entries

1 Answers1