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Strangest language feature
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In JavaScript:
'5' + 3 gives '53'
Whereas
'5' - 3 gives 2
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edited Sep 21 '10 at 10:21
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What are the pros and cons of performing calculations in sql vs. in your application
...engine is likely to have a more efficient decimal arithmetic routines than Java.
Generally though for row level calculations there is not much difference.
Where it does make a difference is:
Aggregate calculations like SUM(), AVG(),MIN(), MAX() here the database engine will be an order of magnit...
Using Enum values as String literals
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JavaDoc: String java.lang.Enum.name() Returns the name of this enum constant, exactly as declared in its enum declaration. Most programmers should use the toString method in preference to this one, as the toString method ma...
How do you create a static class in C++?
... // etc.
}
But you must remember that "static classes" are hacks in the Java-like kind of languages (e.g. C#) that are unable to have non-member functions, so they have instead to move them inside classes as static methods.
In C++, what you really want is a non-member function that you'll declar...
scheduleAtFixedRate vs scheduleWithFixedDelay
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If you read the Java Doc it will be clearer
ScheduledFuture scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit)
Creates and executes a periodic action that becomes enabled first after the given initial de...
Why does ConcurrentHashMap prevent null keys and values?
The JavaDoc of ConcurrentHashMap says this:
7 Answers
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What does @hide mean in the Android source code?
...ype is a collection of classes and methods that are marked with the @hide Javadoc attribute.
Starting from Android 9 (API level 28), Google introduces new restrictions on the use of non-SDK interfaces, whether directly, via reflection, or via JNI. These restrictions are applied whenever an app re...
Commonly accepted best practices around code organization in JavaScript [closed]
As JavaScript frameworks like jQuery make client side web applications richer and more functional, I've started to notice one problem...
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What is a Manifest in Scala and when do you need it?
...Scala 2.7.2 there is something called Manifest which is a workaround for Java's type erasure. But how does Manifest work exactly and why / when do you need to use it?
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Android : Check whether the phone is dual SIM
...able now from Android 5.1 onwards
Other possible option :
You can use Java reflection to get both IMEI numbers.
Using these IMEI numbers you can check whether the phone is a DUAL SIM or not.
Try following activity :
import android.app.Activity;
import android.os.Bundle;
import android.wid...