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How to set specific java version to Maven
On my machine I have two java versions installed: (1.6 and 1.7 installed manually by me). I need both of them for different projects. But for Maven I need 1.7, now my Maven uses 1,6 java version, how can I set Maven to use 1.7?
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What is this weird colon-member (“ : ”) syntax in the constructor?
...tion about it in any good C++ book.
You should, in most cases, initialize all member objects in the member initialization list (however, do note the exceptions listed at the end of the FAQ entry).
The takeaway point from the FAQ entry is that,
All other things being equal, your code will run...
Match whitespace but not newlines
...ghteen horizontal ones which match \h. \s matches twenty-three characters
All whitespace characters are either vertical or horizontal with no overlap, but they are not proper subsets because \h also matches U+00A0 NO-BREAK SPACE, and \v also matches U+0085 NEXT LINE, neither of which are matched by...
How do I create an immutable Class?
I am working on creating an immutable class.
I have marked all the properties as read-only.
6 Answers
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Cost of len() function
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Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
How to check if a variable is a dictionary in Python?
...t, defaultdict, or Counter from the collections module:
if isinstance(any_object, dict):
But there are even more flexible options.
Supporting abstractions:
from collections.abc import Mapping
if isinstance(any_object, Mapping):
This allows the user of your code to use their own custom implem...
How to convert Java String into byte[]?
...m you appear to be wrestling with is that this doesn't display very well. Calling toString() will just give you the default Object.toString() which is the class name + memory address. In your result [B@38ee9f13, the [B means byte[] and 38ee9f13 is the memory address, separated by an @.
For display ...
What are some uses of decltype(auto)?
...code
For non-generic code, like the initial example you gave, you can manually select to get a reference as a return type:
auto const& Example(int const& i)
{
return i;
}
but in generic code you want to be able to perfectly forward a return type without knowing whether you are dea...
curl: (60) SSL certificate problem: unable to get local issuer certificate
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Actually I struggled for an hour as I did not write path inside quotes. So please take a note here curl.cainfo="/path/to/downloaded/cacert.pem" // Do not forget to write between quotes
– Himanshu Upadhyay
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OnCreateOptionsMenu() not called in Fragment
I have an app which got one activity with 2 fragments placed horizontally.
8 Answers
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