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What is null in Java?
...null is an instanceof.
15.20.2 Type Comparison Operator instanceof
RelationalExpression:
RelationalExpression instanceof ReferenceType
At run time, the result of the instanceof operator is true if the value of the RelationalExpression is not null and the reference could be cast to the R...
Push existing project into Github
...emote add origin <project url>
git push -f origin master
The -f option on git push forces the push. If you don't use it, you'll see an error like this:
To git@github.com:roseperrone/project.git
! [rejected] master -> master (fetch first)
error: failed to push some refs to 'git@gi...
How does git store files?
... content of a directory structure.
Some good references are:
git.github.io/git-reference
You tell Git you want to save a snapshot of your project with the git commit command and it basically records a manifest of what all of the files in your project look like at that point
git immersion
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How to turn on/off ReactJS 'development mode'?
Started using ReactJS's prop validation feature , which as the docs say only works in 'development mode' for performance reasons.
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How to configure encoding in Maven?
...
OK, I found the problem.
I use some reporting plugins. In the documentation of the failsafe-maven-plugin (http://maven.apache.org/plugins/maven-failsafe-plugin/integration-test-mojo.html) I found, that the <encoding> configuration - of course - uses ${project.reporting.outputEncoding} by de...
What is the runtime performance cost of a Docker container?
...al to native performance and faster than KVM in every category.
The exception to this is Docker’s NAT — if you use port mapping (e.g., docker run -p 8080:8080), then you can expect a minor hit in latency, as shown below. However, you can now use the host network stack (e.g., docker run --ne...
Recommended date format for REST GET API
...f not having ugly URI is a concern (e.g. not including the url encoded version of :, -, in you URI) and (human) addressability is not as important, you could also consider epoch time (e.g. http://example.com/start/1331162374). The URL looks a little cleaner, but you certainly lose readability.
Th...
What exactly is Python's file.flush() doing?
I found this in the Python documentation for File Objects :
4 Answers
4
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What does Serializable mean?
...
Serialization is persisting an object from memory to a sequence of bits, for instance for saving onto the disk. Deserialization is the opposite - reading data from the disk to hydrate/create an object.
In the context of your question,...
Do declared properties require a corresponding instance variable?
...
If you are using the Modern Objective-C Runtime (that's either iOS 3.x or greater, or 64-bit Snow Leopard or greater) then you do not need to define ivars for your properties in cases like this.
When you @synthesize the property, the ivar will in effect be synthesized also for you. This...