Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]

If possible, you should design your code such that the collections aren't null in the first place.

null collections are bad practice (for this reason); you should use empty collections instead. (eg, Collections.emptyList())

Alternatively, you could make a wrapper class that implements Iterable and takes a collections, and handles a null collection.
You could then write foreach(T obj : new Nullable<T>(list1))

public <T extends Iterable> T nullGuard(T item) {
  if (item == null) {
    return Collections.EmptyList;
  } else {
    return item;
  }
}

or, if saving lines of text is a priority (it shouldn't be)

public <T extends Iterable> T nullGuard(T item) {
  return (item == null) ? Collections.EmptyList : item;
}

would allow you to write

for (Object obj : nullGuard(list)) {
  ...
}

Of course, this really just moves the complexity elsewhere.

Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]

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