Java Utililty Methods List Intersect

for (int i = 0; i < lst1.size(); i++) {
    Object obj1 = lst1.get(i);
    if (!lst2.contains(obj1))
        lst1.remove(i--);

if (list1 == null || list1.isEmpty() || list2 == null || list2.isEmpty()) {
    return Collections.emptyList();
List<T> result = new ArrayList<T>();
result.addAll(list1);
result.retainAll(list2);
return result;

List<E> results = create();
boolean seeded = false;
for (List<E> list : lists) {
    if (list != null) {
        if (seeded) {
            results.retainAll(list);
        } else {
            results.addAll(list);
...

final List<T> theResults = new ArrayList<T>(0);
if (in1 == null || in2 == null || in1.isEmpty() || in2.isEmpty()) {
    return theResults;
for (final T anObject : in1) {
    if (anObject == null && in2.contains(null)) {
        theResults.add(anObject);
    } else if (anObject != null && in2.contains(anObject)) {
...

return intersect(a, (Iterable<?>) b);

if (s1.size() > s2.size())
    return intersect2orderedList(s2, s1);
List<Integer> res = new ArrayList<Integer>();
int pos1 = 0, pos2 = 0;
while (pos1 < s1.size() && pos2 < s2.size()) {
    if (s1.get(pos1).equals(s2.get(pos2))) {
        res.add(s1.get(pos1));
        pos1++;
...

int index1 = 0;
int index2 = 0;
while (true) {
    if (index1 >= a.length || index2 >= b.length) {
        break;
    } else {
        final T candidate1 = a[index1];
        final T candidate2 = b[index2];
...

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
List<Date> listDate = new ArrayList<Date>();
for (Date wDate : oDate) {
    for (Date iDate : tDate) {
        String strWDate = sdf.format(wDate).toString();
        String strIDate = sdf.format(iDate).toString();
        if (strWDate.equals(strIDate)) {
            listDate.add(wDate);
...

final ArrayList result = new ArrayList();
final Iterator iterator = list2.iterator();
while (iterator.hasNext()) {
    final Object o = iterator.next();
    if (list1.contains(o))
        result.add(o);
return result;
...

final ArrayList result = new ArrayList();
final Iterator iterator = list2.iterator();
while (iterator.hasNext()) {
    final Object o = iterator.next();
    if (list1.contains(o)) {
        result.add(o);
return result;