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How do I measure time elapsed in Java? [duplicate]
...- starts;
}
public long time(TimeUnit unit) {
return unit.convert(time(), TimeUnit.MILLISECONDS);
}
}
Usage:
TimeWatch watch = TimeWatch.start();
// do something
long passedTimeInMs = watch.time();
long passedTimeInSeconds = watch.time(TimeUnit.SECONDS);
Aft...
how does array[100] = {0} set the entire array to 0?
...the elements that don't have a specified value, the compiler initializes pointers to NULL and arithmetic types to zero (and recursively applies this to aggregates).
The behavior of this code in C++ is described in section 8.5.1.7 of the C++ specification (online draft of C++ spec): the compiler ag...
How do I check if a string is valid JSON in Python?
... #prints True
print is_json('{"foo":[5,6.8],"foo":"bar"}') #prints True
Convert a JSON string to a Python dictionary:
import json
mydict = json.loads('{"foo":"bar"}')
print(mydict['foo']) #prints bar
mylist = json.loads("[5,6,7]")
print(mylist)
[5, 6, 7]
Convert a python object to JSON str...
Powershell v3 Invoke-WebRequest HTTPS error
...tePolicy {
public bool CheckValidationResult(
ServicePoint srvPoint, X509Certificate certificate,
WebRequest request, int certificateProblem) {
return true;
}
}
"@
[System.Net.ServicePointManager]::CertificatePolicy = New-Object TrustAllCertsPo...
Why use the SQL Server 2008 geography data type?
...lDegrees = 1
Begin
set @X = 1
END
Else
Begin
set @X = 24
End
-- convert to decimal degrees
set @Lat1 = @Latitude1 * @X
set @Long1 = @Longitude1 * @X
set @Lat2 = @Latitude2 * @X
set @Long2 = @Longitude2 * @X
-- convert to radians: radians = (degrees/180) * PI
set @Lat1 = (@Lat1 / 180) * @...
What is tail call optimization?
...earn more about this, I suggest reading the first chapter of Structure and Interpretation of Computer Programs.
– Kyle Cronin
Nov 22 '08 at 16:05
15
...
What should I do if two libraries provide a function with the same name generating a conflict?
...
Under Windows, you could use LoadLibrary() to load one of those libraries into memory and then use GetProcAddress() to get the address of each function you need to call and call the functions through a function pointer.
e.g.
HMODULE lib = LoadLibrary("foo.dll");
void *p = GetProcAddress(lib, "bar...
Volatile boolean vs AtomicBoolean
...
They are just totally different. Consider this example of a volatile integer:
volatile int i = 0;
void incIBy5() {
i += 5;
}
If two threads call the function concurrently, i might be 5 afterwards, since the compiled code will be somewhat similar to this (except you cannot synchronize on...
What's the purpose of using braces (i.e. {}) for a single-line if or loop?
...
Let's attempt to also modify i when we increment j:
int j = 0;
for (int i = 0 ; i < 100 ; ++i)
if (i % 2 == 0)
j++;
i++;
Oh no! Coming from Python, this looks ok, but in fact it isn't, as it's equivalent to:
int j = 0;
for (int i = 0 ; i < 100 ; ++...
Alarm Manager Example
...ge yourPackage;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.PowerManager;
import android.widget.Toast;
public class Alarm extends BroadcastReceiver
{ ...