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What is Persistence Context?
...erence/en/html/architecture.html
In Java EE, a persistence context is normally accessed via an EntityManager.
http://docs.oracle.com/javaee/6/api/javax/persistence/EntityManager.html
The various states an entity can have and the transitions between these are described below:
http://docs.jboss.or...
Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...
When is a C++ destructor called?
Basic Question: when does a program call a class' destructor method in C++? I have been told that it is called whenever an object goes out of scope or is subjected to a delete
...
How do I add a library project to Android Studio?
... well-known Android library is available in a Maven repository and its installation takes only one line of code in the app/build.gradle file:
dependencies {
compile 'com.jakewharton:butterknife:6.0.0'
}
Adding the library
Here is the full process of adding external Android library to our pr...
Building and running app via Gradle and Android Studio is slower than via Eclipse
...-Dfile.encoding=UTF-8
# When configured, Gradle will run in incubating parallel mode.
# This option should only be used with decoupled projects. More details, visit
# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
org.gradle.parallel=true
# Enables ne...
Fatal error: Class 'ZipArchive' not found in
I have a problem that I install 'Archive_Zip 0.1.1' on Linux server, but when I try to run the script to create the zip file it gives the fatal error
...
PHP PDO returning single row
...
Do you really need to LIMIT 1 all the time though? Knowing that you're selecting a UNIQUE value comes to mind.
– Super Cat
Feb 1 '17 at 3:10
...
Should Github be used as a CDN for javascript libraries? [closed]
.... The last one means less total work for everybody, so it's clearly a win all around, and is more likely the more often we (developers) rely on the CDNs to serve our javascript.
...
How do I write a custom init for a UIView subclass in Swift?
...
The init(frame:) version is the default initializer. You must call it only after initializing your instance variables. If this view is being reconstituted from a Nib then your custom initializer will not be called, and instead the init?(coder:) version will be called. Since Swift now req...
Convert NSArray to NSString in Objective-C
...
Won't this accomplish the same thing as calling [array description]?
– TechZen
Dec 1 '09 at 20:55
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