In Java, how to traverse two lists at the same time?

Question

E.g.

for(String str : list1) {
...
}

for(String str : list2) {
...
}

suppose we are sure that list1.size() equals list2

Answer 1

for(int i = 0; i< list1.size(); i++){
  String str1 = list1.get(i);
  String str2 = list2.get(i);
  //do stuff
}