CODEWITHSUNDEEP
javaarraysarraylistiterator
Nina
Nina

Reputation: 99

Iterating through a List of Arrays and printing every element within the Arrays

I seem to be having trouble in the logic of my problem. What I am trying to do is have a List of Arrays. Each Array contains 2 String.

I am trying to iterate through my List and then printing the elements of the arrays. I seem to get stuck in printing the first Array (which is what my code does), though I am stuck in the logic.

    public static void main(String[] args) {
    List<List<String>> addresses = new ArrayList<List<String>>();

    ArrayList<String> singleAddress1 = new ArrayList<String>();
    singleAddress1.add("17 Fake Street");
    singleAddress1.add("18 Fake Street");
    ArrayList<String> singleAddress2 = new ArrayList<String>();
    singleAddress2.add("Phoney town");
    singleAddress2.add("not real town");
    ArrayList<String> singleAddress3 = new ArrayList<String>();
    singleAddress3.add("sillyname town");
    singleAddress3.add("alsosilly town");
    addresses.add(singleAddress1);
    addresses.add(singleAddress2);
    addresses.add(singleAddress3);

    System.out.print("Original contents of al: " + addresses + "\n");
    Iterator itr = addresses.iterator();
    while (itr.hasNext()) {
        Object element = itr.next();
        System.out.print(element + "\n");
        for (int i = 0; i < singleAddress1.size(); i++) {
            System.out.println(singleAddress1.get(i));
        }
        itr.remove();
    }
}
}

Upvotes: 0

Views: 190

Answers (2)

SMA
SMA

Reputation: 37083

Whilst you are iterating over the outer array list addresses, internally you end up iterating on same singleAddress1 instead of all the list elements which you would get from iterator using for (int i = 0; i < singleAddress1.size(); i++) {.

Your iteration loop should be:

Iterator<List<String>> itr = addresses.iterator();
while (itr.hasNext()) {
    List<String> element = itr.next();
    ^^^^^^^^^^^^
    System.out.print(element + "\n");
    for (int i = 0; i < element.size(); i++) {
                        ^^^^^^^^
        System.out.println(element.get(i));
    }
    itr.remove();
}

Upvotes: 2

Sarthak Mittal
Sarthak Mittal

Reputation: 6114

Why don't you use a simple for-each loop:

for(List<String> list:addresses)
{
    for(String str:list)
    {
        System.out.println(str);
    }
}

Upvotes: 1

Related Questions