java.lang.ClassCastException: [Ljava.lang.String; cannot be cast to java.util.List [duplicate]

Question

I have a List, which I am trying to use in 2 different ways...

private List<List<List<String>>> mListSelectedsWeekDAY;

// technique 1
for(int t = 0; t < mListSelectedsWeekDAY.get(0).get(0).size();t++){
    ...
}

// technique 2
List<String> tmpList = mListSelectedsWeekDAY.get(0).get(0);

And my list is populated like this...

mListSelectedsSDAY = new ArrayList<List<List<String>>>(); 
for (int i = 0; i < mListTimeBand.size(); i++) { 
    List<List<String>> tmp2 = new ArrayList<List<String>>(); 
    for (int j = 0; j < mListTimeBand.get(i).getTimeBandDefList().getTimeBandDefini().size(); j++) { 
        List<String> tmp1 = new ArrayList<String>(); 
        if (mListTimeBand.get(i).getTimeBandDefList().getTimeBandDefini().get(j).isAllSpeci‌​alDays()) { 
            for (int t = 0; t < mListSDayType.size(); t++) { 
                tmp1.add(mListSDayType.get(t).getSpecialDayName()); 
            } 
        }
        tmp2.add(tmp1); 
    }

    mListSelectedsSDAY.add(tmp2); 
}

However my code it always giving the following error...

java.lang.ClassCastException: [Ljava.lang.String; cannot be cast to java.util.List

Could someone please help me understand why this is happening.

Answer 1

One possible situation may be is that, in your series of Get methods(), you are moving ahead to get Strings and assigning it to List variables.

Answer 2

You actually have a List<List<String>>, not a List<List<List<String>>>.

You must be using a raw List type somewhere for this to happen