gistfile1.java

Set<WeakReference<TextView>> toRemove = new HashSet<WeakReference<TextView>>();

for (WeakReference<TextView> weakRef : textviews) {
    TextView textView = weakRef.get();

    if (textView != null) {
        // do stuff here
    } else {
        toRemove.add(weakRef);
    }
}

// remove all the unnecessary WeakReferences from your set
textviews.removeAll(toRemove);