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Why is the Java main method static?
...ntire class - sometimes you have an instance that hasn't been initialized, and you have to check for it in every method that could be called.
There are just too many edge cases and ambiguities for it to make sense for the JVM to have to instantiate a class before the entry point is called. That's ...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versi...
Reducing memory usage of .NET applications?
...memory footprint is all about demystifying the working set, process memory and how to perform accurate calculations on your total in-RAM consumption.
I will not say that you should ignore the memory footprint of your application -- obviously, smaller and more efficient does tend to be desirable. Ho...
Practical uses of git reset --soft?
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git reset is all about moving HEAD, and generally the branch ref.
Question: what about the working tree and index?
When employed with --soft, moves HEAD, most often updating the branch ref, and only the HEAD.
This differ from commit --amend as:
it doesn't cre...
Extracting bits with a single multiplication
I saw an interesting technique used in an answer to another question , and would like to understand it a little better.
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“Public key certificate and private key doesn't match” when using Godaddy issued certificate [closed
... the web server to the new load balancer. Amazon requires the private key and certs to be in PEM format, so I used the "rekey" tool at GoDaddy to create new certs. When I load those in the load balancer setup screen on AWS Mgmt Console, I get the error message: "Public Key Certificate and Private ...
What's the difference between emulation and simulation? [duplicate]
In simple understandable terms, what is the difference between the two terms?
10 Answers
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Stack Memory vs Heap Memory [duplicate]
I am programming in C++ and I am always wondering what exactly is stack memory vs heap memory. All I know is when I call new, I would get memory from heap. If if create local variables, I would get memory from stack. After some research on internet, the most common answer is stack memory is temporar...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
I'm used to using relational databases like MySQL or PostgreSQL, and combined with MVC frameworks such as Symfony, RoR or Django, and I think it works great.
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What does “Could not find or load main class” mean?
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The java <class-name> command syntax
First of all, you need to understand the correct way to launch a program using the java (or javaw) command.
The normal syntax1 is this:
java [ <options> ] <class-name> [<arg> ...]
where &...