Why am I getting duplicates when combining multiple ArrayLists?

Question

Why I am getting duplicate entries in my ArrayList<String[]>?

allStepsJSONStringArray contains an array of single strings in the format of JSON
I loop through and pass each JSON string to a function that writes it to a temporary internal file
I read the file
Then pass it to getStepsArray() which breaks down the JSON string and puts each entry into a String[]

Loop to add to master ArrayList - allStepsArray

for (int i = 0; i < allStepsJSONStringArray.size(); i++) {
    writer.writeToInternal(allStepsJSONStringArray.get(i));
    reader.readFromInternal(writer.filename); 
    stepsArray = reader.getStepsArray();
    for (int s = 0; s < stepsArray.size(); s++) {
        allStepsArray.add(stepsArray.get(s));
    }
}

getStepsArray()

public ArrayList<String[]> getStepsArray() {
    try {
        JSONObject jObject = new JSONObject(jsonString);
        JSONArray jArray = jObject.getJSONArray("steps");
        String stepOrder = null;
        String stepName = null;
        String stepType = null;
        String stepId = null;
        String checklistId = null;
        String checklistName = null;

        for (int i = 0; i < jArray.length(); i++) {
            stepOrder = jArray.getJSONObject(i).getString("order");
            stepName = jArray.getJSONObject(i).getString("name");
            stepType = jArray.getJSONObject(i).getString("type");
            stepId = jArray.getJSONObject(i).getString("id");
            checklistId = jObject.getString("checklistId");
            checklistName = jObject.getString("checklistName");
            stepsArray.add(new String[] {stepOrder, stepName, stepType, stepId, checklistName, checklistId});
        }


    } catch (Exception e) {
        e.printStackTrace();
    }
    return stepsArray;
}

Because you don't seem to ever reset stepsArray. The second time you add elements to it, the previous elements will still be there and will get added to allStepsArray again. — Sotirios Delimanolis
– Sotirios Delimanolis, Commented Jan 8, 2014 at 3:09
@SotiriosDelimanolis You are correct! If you want some points, create an answer so I can accept it! — The Nomad
– The Nomad, Commented Jan 8, 2014 at 3:13

Sotirios Delimanolis · Accepted Answer · 2014-01-08 03:13:53Z

1

Word for word:

Because you don't seem to ever reset stepsArray. The second time you add elements to it, the previous elements will still be there and will get added to allStepsArray again.

answered Jan 8, 2014 at 3:13

Sotirios Delimanolis

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1 Comment

Sotirios Delimanolis Over a year ago

@TheNomad Don't worry about it, as long as you've solved your issue.

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