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How to get the ThreadPoolExecutor to increase threads to max before queueing?
...e TPE will add additional threads. If the pool is already at max threads, then the RejectedExecutionHandler will be called. It is the handler which then does the put(...) into the queue.
It certainly is strange to write a queue where offer(...) can return false and put() never blocks so that's th...
How to detect the OS from a Bash script?
...ork. I'm not sure about win32 though.
if [[ "$OSTYPE" == "linux-gnu"* ]]; then
# ...
elif [[ "$OSTYPE" == "darwin"* ]]; then
# Mac OSX
elif [[ "$OSTYPE" == "cygwin" ]]; then
# POSIX compatibility layer and Linux environment emulation for Windows
elif [[ "$OSTYPE" == "msys" ]...
Select SQL Server database size
...NAME(database_id)
, log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, row_size_mb = CAST(SUM(CASE WHEN type_desc = 'ROWS' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, total_size_mb = CAST(SUM(size) * 8. / 1024 AS DECIMAL(8,2))
FROM sys.mast...
Why do browsers match CSS selectors from right to left?
...by browser engines from right to left. So they first find the children and then check their parents to see if they match the rest of the parts of the rule.
...
Is it safe to resolve a promise multiple times?
...ected), that is it for a defered object - it is done.
If you should call then(...) on it's promise again, you should immediately get the (first) resolved/rejected result.
Additional calls to resolve() will not (should not?) have any effect. Not sure what happens if you attempt to reject a defere...
How to make “if not true condition”?
...
try
if ! grep -q sysa /etc/passwd ; then
grep returns true if it finds the search target, and false if it doesn't.
So NOT false == true.
if evaluation in shells are designed to be very flexible, and many times doesn't require chains of commands (as you have...
How can I check if a directory exists in a Bash shell script?
...sts in a shell script, you can use the following:
if [ -d "$DIRECTORY" ]; then
# Control will enter here if $DIRECTORY exists.
fi
Or to check if a directory doesn't exist:
if [ ! -d "$DIRECTORY" ]; then
# Control will enter here if $DIRECTORY doesn't exist.
fi
However, as Jon Ericson poi...
Test if a command outputs an empty string
...You can test for a non-empty string in Bash like this:
if [[ $(ls -A) ]]; then
echo "there are files"
else
echo "no files found"
fi
Note that I've used -A rather than -a, since it omits the symbolic current (.) and parent (..) directory entries.
Note: As pointed out in the comments, comm...
How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?
...io 2015 Update3 I have this feature.
Just by highlighting properties and then press Ctrl + . and then press Generate Constructor.
For example, if you've highlighted two properties it will suggest you to create a constructor with two parameters and if you've selected three it will suggest one wit...
Get the time difference between two datetimes
...tal duration is less than 24 hours:
var now = "04/09/2013 15:00:00";
var then = "04/09/2013 14:20:30";
moment.utc(moment(now,"DD/MM/YYYY HH:mm:ss").diff(moment(then,"DD/MM/YYYY HH:mm:ss"))).format("HH:mm:ss")
// outputs: "00:39:30"
If you have 24 hours or more, the hours will reset to zero wit...