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How to print a float with 2 decimal places in Java?
...esentation of a floating-point number (f) from the start of the format specifier (%).
There are other conversion characters you can use besides f:
d: decimal integer
o: octal integer
e: floating-point in scientific notation
...
Maximum packet size for a TCP connection
...ld use a lower one. With the advent of jumbo frames, there is no real specified maximum, and the maximum varies depending on the hardware and driver.
– WhirlWind
Apr 10 '10 at 17:08
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Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?
Is there a better way than the following to check to see if a string is nil OR has a length of 0 in Ruby?
16 Answers
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setBackground vs setBackgroundDrawable (Android)
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It's deprecated but it still works so you could just use it. But if you want to be completly correct, just for the completeness of it... You'd do something like following:
int sdk = android.os.Build.VERSION.SDK_INT;
if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) {
setBackgroun...
Vagrant's port forwarding not working [closed]
...omments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that there are no fir...
Debug vs. Release performance
...piled at all
some loop variables are taken out of the loop by the compiler if they are proven to be invariants
code written under #debug directive is not included, etc.
The rest is up to the JIT.
Full list of optimizations here courtesy of Eric Lippert.
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gcc warning" 'will be initialized after'
I am getting a lot of these warnings from 3rd party code that I cannot modify.
Is there a way to disable this warning or at least disable it for certain areas (like #pragma push/pop in VC++)?
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What are Runtime.getRuntime().totalMemory() and freeMemory()?
...aximum amount of memory that the Java virtual machine will attempt to use. If there is no inherent limit then the value Long.MAX_VALUE will be returned.
freeMemory()
Returns the amount of free memory in the Java Virtual Machine. Calling the gc method may result in increasing the value returned by...
OO Design in Rails: Where to put stuff
...e huge ActiveRecord subclasses and huge controllers is quite natural (even if you do use a controller per resource). If you were to create deeper object worlds, where would you put the classes (and modules, I suppose)? I'm asking about views (in the Helpers themselves?), controllers and models.
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doGet and doPost in Servlets
...raw URL in browser address bar, etcetera will all fire a HTTP GET request. If a Servlet is listening on the URL in question, then its doGet() method will be called. It's usually used to preprocess a request. I.e. doing some business stuff before presenting the HTML output from a JSP, such as gatheri...