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Java Singleton and Synchronization
... case where you have two threads that call getInstance() at the same time. Now imagine T1 executes just past the instance == null check, and then T2 runs. At this point in time the instance is not created or set, so T2 will pass the check and create the instance. Now imagine that execution switches ...
How should I store GUID in MySQL tables?
...tes with an Integer. Since he put that challenge out there to me I thought now was a good time to mention it. That being said...
You can store a guid as a CHAR(16) binary if you want to make the most optimal use of storage space.
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How do you install an APK file in the Android emulator?
I finally managed to obfuscate my Android application, now I want to test it by installing the APK file and running it on the emulator.
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Ignore files that have already been committed to a Git repository [duplicate]
...m your system use: git rm --cached filename
To untrack every file that is now in your .gitignore:
First commit any outstanding code changes, and then, run this command:
git rm -r --cached .
This removes any changed files from the index(staging area), then just run:
git add .
Commit it:
g...
Android Bitmap to Base64 String
...Stream is = new Base64InputStream( new FileInputStream(yourFileHere) );
//Now that we have the InputStream, we can read it and put it into the String
final StringWriter writer = new StringWriter();
IOUtils.copy(is , writer, encoding);
final String yourBase64String = writer.toString();
As you can ...
Odd behavior when Java converts int to byte?
...resent it as an int (32 bits) you simply copy the 1 to the left 24 times.
Now, one way to read a negative two's complement number is to start with the least significant bit, move left until you find the first 1, then invert every bit afterwards. The resulting number is the positive version of that ...
Avoid modal dismiss on enter keypress
...n to be fired. I changed it to an anchor instead and it works as expected now (enter submits the form and does not close the modal).
<a class="close" data-dismiss="modal">&times;</a>
Without seeing your source, I can't confirm that your cause is the same though.
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Find the closest ancestor element that has a specific class
...
Update: Now supported in most major browsers
document.querySelector("p").closest(".near.ancestor")
Note that this can match selectors, not just classes
https://developer.mozilla.org/en-US/docs/Web/API/Element.closest
For legac...
Java Date vs Calendar
... as java.util.Date, java.util.Calendar, and java.text.SimpleDateFormat are now legacy, supplanted by the java.time classes built into Java 8 and later. See Tutorial by Oracle.
– Basil Bourque
Oct 19 '18 at 19:51
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When & why to use delegates? [duplicate]
... in Guass3.
With Delegates
public delegate double Integrand(double x);
Now we can define some static (or not) functions adhering to that prototype:
class Program {
public delegate double Integrand(double x);
// Define implementations to above delegate
// with similar input and outp...