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How to check edittext's text is email address or not?
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With the introduction of new top level domains that are longer than 2-4 characters, this needs to be updated. Simply replace the {2.4}" with a "+". (e.g. joe@century21.realtor)
– Dave Owens
Ap...
What does “where T : class, new()” mean?
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That is a constraint on the generic parameter T. It must be a class (reference type) and must have a public parameter-less default constructor.
That means T can't be an int, float, double, DateTime or any other struct (value type).
It could...
How to get Latitude and Longitude of the mobile device in android?
...ness.
LocationFinder
public class LocationFinder extends Activity {
int increment = 4;
MyLocation myLocation = new MyLocation();
// private ProgressDialog dialog;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView...
Is the ternary operator faster than an “if” condition in Java [duplicate]
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Ternary Operator example:
int a = (i == 0) ? 10 : 5;
You can't do assignment with if/else like this:
// invalid:
int a = if (i == 0) 10; else 5;
This is a good reason to use the ternary operator. If you don't have an assignment:
(i == 0) ? foo ...
Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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How do I get the size of a java.sql.ResultSet?
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Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the entire data.
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Clang optimization levels
...m-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments
As pointed out in Geoff Nixon's answer (+1), clang additionally runs some higher level optimizations, which we can retrieve with:
echo 'int;' | clang -xc -O3 - -o /dev/null -\#\#\#
Documentation of individual passes is availabl...
Do try/catch blocks hurt performance when exceptions are not thrown?
...Stopwatch w = new Stopwatch();
double d = 0;
w.Start();
for (int i = 0; i < 10000000; i++)
{
try
{
d = Math.Sin(1);
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
w.Stop();
Conso...
iPhone Data Usage Tracking/Monitoring
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The thing is that pdp_ip0 is one of interfaces, all pdpXXX are WWAN interfaces dedicated to different functions, voicemail, general networking interface.
I read in Apple forum that :
The OS does not keep network statistics on a process-by-process basis. As suc...
Why can't variable names start with numbers?
...a string of digits would be a valid identifier as well as a valid number.
int 17 = 497;
int 42 = 6 * 9;
String 1111 = "Totally text";
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