gistfile1.txt

public class Thunk<T> {
	private volatile T value;
	private final Provider<T> provider;

	public Thunk(Provider<T> provider) {
		this.provider = provider;
	}

	/**
	 * Data race is possible here: there can be multiple invocations of creator func
	 */
	public T get() {
		if (null == value) {
			value = provider.get();
		}

		return value;
	}
}