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Does using final for variables in Java improve garbage collection?
...sweep GC algorithm, which has to examine all the live refereces in the GC "root" locations (like all the objects in the current call stack). Each live object is "marked" as being alive, and any object referred to by a live object is also marked as being alive.
After the completion of the mark phase...
How can I get the external SD card path for Android 4.0+?
...nment.getExternalStorageDirectory();
//Retrieve the External Storages root directory:
final String externalStorageRootDir;
if ( (externalStorageRootDir = primaryExternalStorage.getParent()) == null ) { // no parent...
Log.d(TAG, "External Storage: " + primaryExternalStorage + "...
Where should Rails 3 custom validators be stored?
...o your /config/application.rb file:
config.autoload_paths += %W["#{config.root}/lib/validators/"]
Then Rails will automatically load your validators on start up (just like /config/initializers/), but you keep the clean structure of having your validators in one nice, well named spot.
...
ruby system command check exit code
...capture it as part of your REPL command [10] pry(main)> system("touch /root/test 2> /dev/null") => false [11] pry(main)> $?.exitstatus => 0 [12] pry(main)> system("touch /root/test 2> /dev/null"); $?.exitstatus => 1
– lardcanoe
Mar 9 '1...
How do you create a read-only user in PostgreSQL?
...user in PostgreSQL that can only do SELECTs from a particular database. In MySQL the command would be:
11 Answers
...
Is it possible to declare a variable in Gradle usable in Java?
... %c - %m%n</pattern>
</layout>
</appender>
<root level="info">
<appender-ref ref="FILE"/>
</root>
</configuration>
Files:
build.gradle
src/main/java/example/HelloWorld.java
src/test/java/example/HelloWorldTest.java
src/test/resources/logb...
Do you use source control for your database items? [closed]
...
With Mysql Workbench you can have all that in a structured file(xml) that can be opened and handled with a GUI. Being xml just text, yes it can be versioning without having to type single sql sentence.
– lev...
Primary key or Unique index?
...hen it tries to insert the value 1 into this column for a second time.
In MySQL a unique constraint allows multiple NULLs.
It is possible to make a unique index on mutiple columns.
Primary key versus unique index
Things that are the same:
A primary key implies a unique index.
Things that are...
Fastest way to count exact number of rows in a very large table?
...
The fastest way by far on MySQL is:
SHOW TABLE STATUS;
You will instantly get all your tables with the row count (which is the total) along with plenty of extra information if you want.
...
Render HTML to PDF in Django site
...rServerClient(models.Manager):
def __handle_exception(self, exception_root, exception_id, exec_info ):
type, value, traceback = exec_info
raise JasperServerClientError(exception_root, exception_id), None, traceback
# 01: REPORT-METADATA
# get resource description to ...