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Is there more to an interface than having the correct methods
...
How did this get selected as the answer? It's a brief description of why polymorphism is useful, but as the poster above said, I would expect a better explanation of multiple interfaces and even more importantly when it is appropriate to use ...
Null vs. False vs. 0 in PHP
...mpatibility). Despite the design wishing some consistency (outlined in the selected answer here), it all get confusing when you consider method returns that use false/null in not-so-easy to reason ways.
You will often see null being used when they are already using false for something. e.g. filter_i...
how to provide a swap function for my class?
...declared in the same namespace as the type for which they are provided get selected through argument-dependent lookup over this generic version.
But note that directly using the std::swap function for a user-defined class calls the generic version of std::swap instead of the user-defined swap:
my...
IOException: read failed, socket might closed - Bluetooth on Android 4.3
...ect() throws IOException {
boolean success = false;
while (selectSocket()) {
adapter.cancelDiscovery();
try {
bluetoothSocket.connect();
success = true;
break;
} catch (IOException e) {
...
What are the implications of using “!important” in CSS? [duplicate]
...ork when the browser decides how CSS affects the page. The more specific a selector is, the more importance is added to it. This usually coincides with how often the selected element occurs. For example:
button {
color: black;
}
button.highlight {
color: blue;
font-size: 1.5em;
}
b...
Does “git fetch --tags” include “git fetch”?
...ly fetches tags on tracked branches. We have a script that allows users to select a working branch, so by default there are many branches that are not currently tracked by an individual.
– davidA
Jul 30 '09 at 22:46
...
Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...
PostgreSQL 9.5
PostgreSQL 9.5 incorporates SELECT ... FOR UPDATE ... SKIP LOCKED. This makes implementing working queuing systems a lot simpler and easier. You may no longer require an external queueing system since it's now simple to fetch 'n' rows that no other sess...
Is it worth hashing passwords on the client side
... that such a replay attack cannot work, usually, by allowing the client to select a bunch of random bits, which are hashed along with the password, and also submitted in the clear to the server.
On the server:
generate a few bits of random
send these bits (in clear text) to the client
On the c...
ExecuteReader requires an open and available Connection. The connection's current state is Connectin
...on = new SqlConnection(connectionString))
{
var queryString = "SELECT PromotionID, PromotionTitle, PromotionURL FROM Promotion WHERE PromotionID=@PromotionID";
using (var da = new SqlDataAdapter(queryString, connection))
{
// you could also use a SqlDataReader...
Which parallel sorting algorithm has the best average case performance?
...gistration which is free):
University lectures:
Parallel Partitioning for Selection and Sorting
Parallel Sorting Algorithms Lecture
Parallel Sorting Algorithms Lecture 2
Parallel Sorting Algorithms Lecture 3
Other sources and papers:
A novel sorting algorithm for many-core architectures based on ...