[Demonstration 1]

[Buggy Method]
@Override
public boolean equals(Object o) {
    if (this == o)
        return true;
    if (o == null || getClass() != o.getClass())
        return false;
    Book book = (Book) o;
    if (pages != book.pages)
        return false;
    if (Float.compare(book.price, price) != 0)
        return false;
    if (id != null ? !id.equals(book.id) : book.id != null)
        return false;
    if (title != null ? !title.equals(book.title) : book.title != null)
        return false;
    if (subtitle != null ? !subtitle.equals(book.subtitle) : book.subtitle != null)
        return false;
    if (isbn10 != null ? !isbn10.equals(book.isbn10) : book.isbn10 != null)
        return false;
    if (isbn13 != null ? !isbn13.equals(book.isbn13) : book.isbn13 != null)
        return false;
    if (author != null ? !author.equals(book.author) : book.author != null)
        return false;
    if (publisher != null ? !publisher.equals(book.publisher) : book.publisher != null)
        return false;
    if (summary != null ? !summary.equals(book.summary) : book.summary != null)
        return false;
    if (pubDate != null ? !pubDate.equals(book.pubDate) : book.pubDate != null)
        return false;
    if (originTitle != null ? !originTitle.equals(book.originTitle) : book.originTitle != null)
        return false;
    if (binding != null ? !binding.equals(book.binding) : book.binding != null)
        return false;
    if (translator != null ? !translator.equals(book.translator) : book.translator != null)
        return false;
    if (imageMedium != null ? !imageMedium.equals(book.imageMedium) : book.imageMedium != null)
        return false;
    if (imageLarge != null ? !imageLarge.equals(book.imageLarge) : book.imageLarge != null)
        return false;
    return levelNum != null ? levelNum.equals(book.levelNum) : book.levelNum == null;
}

[Buggy Hunk]
if (Float.compare(book.price, price) != 0) return false;

[Patch]
if (price != null ? !price.equals(book.price) : book.price != null) return false;

[Demonstration 2]

[Buggy Method]
@Override
public void onStop() {
    super.onStop();
    view.stop();
    manager.unregisterReceiver(receiver);
}

[Buggy Hunk]
manager.unregisterReceiver(receiver);

[Patch]
handler.unregister(listener);

[Demonstration 3]

[Buggy Method]
@Override
public void onPause() {
    super.onPause();
    getActivity().unregisterReceiver(newPartnerMessageReceiver);
    getActivity().unregisterReceiver(onBlockEnactedReceiver);
    getActivity().unregisterReceiver(onChangeInLocalityReceiver);
}

[Buggy Hunk]
getActivity().unregisterReceiver(onChangeInLocalityReceiver);

[Patch]
getActivity().unregisterReceiver(internetAvailableReceiver);