Java Utililty Methods List Zip

ArrayList<Element> result = new ArrayList<Element>();
for (int i = 0; i < l1.size(); i++) {
    result.add(l1.get(i));
    result.add(l2.get(i));
return result;

List<Double> out = new ArrayList<Double>();
for (int i = 0; i < Math.min(a.size(), b.size()); i++)
    out.add(a.get(i) * b.get(i));
return out;

List<List<T>> result = new ArrayList<List<T>>();
for (int i = 0; i < lists.get(0).size(); i++) {
    List<T> l = new ArrayList<T>();
    for (List<T> in : lists) {
        l.add(in.get(i));
    result.add(l);
return result;

List<List<T>> zipped = new ArrayList<List<T>>();
for (List<T> list : lists) {
    for (int i = 0, listSize = list.size(); i < listSize; i++) {
        List<T> zipList;
        if (i >= zipped.size()) {
            zipped.add(zipList = new ArrayList<T>());
        } else {
            zipList = zipped.get(i);
...

List<double[]> result = new ArrayList<double[]>();
int len0 = lists.get(0).length;
int len1 = lists.size();
for (int i = 0; i < len0; i++) {
    double[] array = new double[len1];
    for (int j = 0; j < len1; j++) {
        array[j] = lists.get(j)[i];
    result.add(array);
return result;

if (listOfLists == null) {
    return null;
List<List<E>> result = new ArrayList<List<E>>();
int innerLength = maxInnerSize(listOfLists);
for (int i = 0; i < innerLength; ++i) {
    result.add(new ArrayList<E>());
for (Iterator<List<E>> it1 = listOfLists.iterator(); it1.hasNext();) {
    List<E> innerList = it1.next();
    int index = 0;
    for (Iterator<E> it2 = innerList.iterator(); it2.hasNext(); ++index) {
        E element = it2.next();
        List<E> resultList = result.get(index);
        resultList.add(element);
return result;