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Large Numbers in Java
... compute: 58.1 seconds.
*/
public class Main {
public static void main(String... args) {
int place = args.length > 0 ? Integer.parseInt(args[0]) : 250 * 1000;
long start = System.nanoTime();
BigInteger fibNumber = fib(place);
long time = System.nanoTime() - sta...
android fragment- How to save states of views in a fragment when another fragment is pushed on top o
... data:
public class FragmentA extends Fragment {
private static final String PERSISTENT_VARIABLE_BUNDLE_KEY = "persistentVariable";
private EditText persistentVariableEdit;
public FragmentA() {
setArguments(new Bundle());
}
@Override
public View onCreateView(Layou...
Easiest way to check for an index or a key in an array?
...s actually adapted from the answers for this SO question: How to tell if a string is not defined in a bash shell script?
A wrapper function:
exists(){
if [ "$2" != in ]; then
echo "Incorrect usage."
echo "Correct usage: exists {key} in {array}"
return
fi
eval '[ ${'$3'[$1]+...
Add number of days to a date
...te('Y-m-d', strtotime("+30 days"));
strtotime
expects to be given a string containing a US English date format and will try to parse that format into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 UTC), relative to the timestamp given in now, or the current time if now ...
Is there a conditional ternary operator in VB.NET?
...Here's some more info: Visual Basic If announcement
Example:
Dim foo as String = If(bar = buz, cat, dog)
[EDIT]
Prior to 2008 it was IIf, which worked almost identically to the If operator described Above.
Example:
Dim foo as String = IIf(bar = buz, cat, dog)
...
JPA: How to have one-to-many relation of the same Entity type
... main() method that persists three such entities:
public static void main(String[] args) {
EntityManager em = ... // from EntityManagerFactory, injection, etc.
em.getTransaction().begin();
A parent = new A();
A son = new A();
A daughter = new A();
son.setParent(pa...
Is Java Regex Thread Safe?
...a function that uses Pattern#compile and a Matcher to search a list of strings for a pattern.
5 Answers
...
How do you cast a List of supertypes to a List of subtypes?
...
This lets me write: List<String> myList = (List<String>)(List<?>)(new ArrayList<Integer>()); This would crash at runtime. I prefer something like List<? extends Number> myList = new ArrayList<Integer>();
...
jQuery: Get selected element tag name
...
Note that the string that's returned is in CAPITAL LETTERS. This'll be a gotcha if you're trying to compare it to "div" or "a" for example.
– Hartley Brody
Apr 29 '14 at 23:41
...
Anonymous method in Invoke call
...If you need to pass in parameters, then "captured variables" are the way:
string message = "Hi";
control.Invoke((MethodInvoker) delegate {this.Text = message;});
(caveat: you need to be a bit cautious if using captures async, but sync is fine - i.e. the above is fine)
Another option is to write ...