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What is the difference between ? and Object in Java generics?
...is right way to go to use ResponseEntity<?> on controller level for all my controller functions?
– Irakli
Nov 25 '16 at 7:38
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vector::at vs. vector::operator[]
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I'd say the exceptions that vector::at() throws aren't really intended to be caught by the immediately surrounding code. They are mainly useful for catching bugs in your code. If you need to bounds-check at runtime because e.g. the index comes from user input, you're indeed best of...
Difference between attr_accessor and attr_accessible
...d that makes a getter and a setter. attr_accessible is a Rails method that allows you to pass in values to a mass assignment: new(attrs) or update_attributes(attrs).
Here's a mass assignment:
Order.new({ :type => 'Corn', :quantity => 6 })
You can imagine that the order might also have a d...
Does PHP have threading?
I found this PECL package called threads , but there is not a release yet. And nothing is coming up on the PHP website.
13...
Convert datetime to Unix timestamp and convert it back in python
...m UTC.
If you have, or can upgrade to, Python 3.3 or later, you can avoid all of these problems by just using the timestamp method instead of trying to figure out how to do it yourself. And even if you don't, you may want to consider borrowing its source code.
(And if you can wait for Python 3.4, ...
Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
How to write a simple database engine [closed]
...ny, so I am hoping someone else can point me in the right direction. Basically, I would like information on the following:
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Git pull after forced update
... the working tree since <commit> are discarded.
If you want to actually keep whatever changes you've got locally - do a --soft reset instead. Which will update the commit history for the branch, but not change any files in the working directory (and you can then commit them).
Rebase
You ca...
How to fix corrupted git repository?
... have a corrupted local repo, but a trusted remote.
# This script replaces all your history with that of the remote.
# If there is a .git, it is backed up as .git_old, removing the last backup.
# This does not affect your working tree.
#
# This does not currently work with submodules!
# This will ab...
Is there a difference between foreach and map?
...important point to mention (this is particularly true in Scala) is that a call to map does not result in the execution of its underlying logic until when the expected transformed list is summoned. In contrast, foreach's operation is computed immediately.
– solimant
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