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Most efficient way to check for DBNull and then assign to a variable?
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Old now, but I've recently seen a number of cases where this was exactly what the profiler said to fix. Imagine evaluating large data sets, where every cell needs to make this check. Optimizing that can can reap big rewards. But ...
What is a difference between
... arrays are what we call reifiable types. This means that at runtime Java knows that this array was actually instantiated as an array of integers which simply happens to be accessed through a reference of type Number[].
So, as you can see, one thing is the actual type of the object, and another thin...
Nexus 7 not visible over USB via “adb devices” from Windows 7 x64
...t was only the above (changing to PTP) that enabled my Nexus 7 to show up. Now on to adding support for my apps for tablets - Thanks so much!
– Robbe
Aug 31 '12 at 18:18
6
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Display current time in 12 hour format with AM/PM
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Outmoded now. These formatting codes are now supplanted by the formatting codes of the DateTimeFormatter class, per JSR 310.
– Basil Bourque
Sep 3 '19 at 1:45
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Explaining Python's '__enter__' and '__exit__'
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If you know what context managers are then you need nothing more to understand __enter__ and __exit__ magic methods. Lets see a very simple example.
In this example I am opening myfile.txt with help of open function. The try/finally...
getting the screen density programmatically in android?
...g point scaling factor from the reference density (160dpi). The same value now provided by metrics.densityDpi can be calculated
int densityDpi = (int)(metrics.density * 160f);
share
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improve this...
What is the difference between a var and val definition in Scala?
...ge the state of that object. At the root of it, however, there was a var.
Now, immutability is a good thing for many reasons. First, if an object doesn't change internal state, you don't have to worry if some other part of your code is changing it. For example:
x = new B(0)
f(x)
if (x.value.value ...
Merge development branch with master
...y)
git checkout master
git merge development (there won't be any conflicts now)
There isn't much of a difference in the two approaches, but I have noticed sometimes that I don't want to merge the branch into master yet, after merging them, or that there is still more work to be done before these c...
How does “cat
...;<EOF
SELECT foo, bar FROM db
WHERE foo='baz'
EOF
)
The $sql variable now holds the new-line characters too. You can verify with echo -e "$sql".
2. Pass multi-line string to a file in Bash
$ cat <<EOF > print.sh
#!/bin/bash
echo \$PWD
echo $PWD
EOF
The print.sh file now contains:
...
Test iOS app on device without apple developer program or jailbreak
...lso, you must do this for every .sdk you want to be able to run on device.
Now, in your project settings, you can change Code Signing Identity to Don't Code Sign.
Your app should now build and install on your device successfully.
UPDATE:
There are some issues with iOS 5.1 SDK that this method may no...