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public void useCaseExample() {
  storageAbstraction.loadSomeData();
  filterData();
  doSomeComputation();
  uiAbstraction.presentDataToUser();
}

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// Simple stack implementation, works as expected every time
private Stack<NavItem> navigationStack = new Stack<>();

// ...

// Navigating to a new screen/item in the stack 
navigationStack.push(new NavItem(viewToBeAdded.getClass(), args));

// ...

code-twister

private static String makeFragmentName(int viewId, int index) {
    return "android:switcher:" + viewId + ":" + index;
}

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/**
 * Return the Fragment associated with a specified position.
 */
public abstract Fragment getItem(int position);

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@Override
public Object instantiateItem(View container, int position) {
  if (mCurTransaction == null) {
    mCurTransaction = mFragmentManager.beginTransaction();
  }

  // Do we already have this fragment?
  String name = makeFragmentName(container.getId(), position);
  Fragment fragment = mFragmentManager.findFragmentByTag(name);
  if (fragment != null) {