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Stateless and Stateful Enterprise Java Beans
...s. If stateless session beans do not retain their state in between method calls, why is my program acting the way it is?
7 ...
Querying DynamoDB by date
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Updated Answer:
DynamoDB allows for specification of secondary indexes to aid in this sort of query. Secondary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist w...
R object identification
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I usually start out with some combination of:
typeof(obj)
class(obj)
sapply(obj, class)
sapply(obj, attributes)
attributes(obj)
names(obj)
as appropriate based on what's revealed. For example, try with:
obj <- data.frame(a...
How to create a printable Twitter-Bootstrap page
... type="text/css" media="print" href="print.css">
or one you share for all devices:
<link rel="stylesheet" type="text/css" href="bootstrap.min.css"> # Note there's no media attribute
Then, you can write your styles for printers in the separate stylesheets or in the shared one using medi...
How should I handle “No internet connection” with Retrofit on Android
...an> isNetworkActive) {
isNetworkActive.subscribe(
_isNetworkActive -> this.isNetworkActive = _isNetworkActive,
_error -> Log.e("NetworkActive error " + _error.getMessage()));
}
@Override
public Response intercept(Interceptor.Chain chain) thr...
Passing an Array as Arguments, not an Array, in PHP
...dard func($arg1, $arg2) manner. But now I'm lost on how to do it. I recall the manner of passing by reference, how to "glob" incoming parameters ... but not how to de-list the array into a list of arguments.
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How to concatenate string variables in Bash
...he habit of putting $foo inside the double quotes, for the times when it really does matter.
– Cascabel
Nov 15 '10 at 7:56
109
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Powershell equivalent of bash ampersand (&) for forking/running background processes
...file.txt is in the current directory.
The output is not displayed automatically. You need to run Receive-Job with the ID of the job as parameter.
NOTE: Regarding your initial example, "bg sleep 30" would not work because sleep is a Powershell commandlet. Start-Process only works when you actually ...
How to get the current time in milliseconds from C in Linux?
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This can be achieved using the POSIX clock_gettime function.
In the current version of POSIX, gettimeofday is marked obsolete. This means it may be removed from a future version of the specification. Application writers are encouraged to use the clock_gettime functi...
Getting image dimensions without reading the entire file
...ative (drop the sign then). As for JPEG - 0xC0 isn't the only header. Basically all of 0xC0 to 0xCF except 0xC4 and 0xCC are valid headers (you can easily get them in interlaced JPGs). And, to make things more fun, height can be 0 and specified later in a 0xDC block. See w3.org/Graphics/JPEG/itu-t81...