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How do I call one constructor from another in Java?
Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? And what could be the best way to call another constructor (if there are several ways to do it)?
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How to check if PHP array is associative or sequential?
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You have asked two questions that are not quite equivalent:
Firstly, how to determine whether an array has only numeric keys
Secondly, how to determine whether an array has sequential numeric keys, starting from 0
Consider which of these behaviours you actually nee...
jQuery SVG vs. Raphael [closed]
...ughts:
Raphael
Pros: a good starter library, easy to do a LOT of things with SVG quickly. Well written and documented. Lots of examples and Demos. Very extensible architecture. Great with animation.
Cons: is a layer over the actual SVG markup, makes it difficult to do more complex things with SVG...
Why does ConcurrentHashMap prevent null keys and values?
...oncurrentMaps
(ConcurrentHashMaps, ConcurrentSkipListMaps) is that ambiguities that
may be just barely tolerable in non-concurrent maps can't be
accommodated. The main one is that if map.get(key) returns null, you
can't detect whether the key explicitly maps to null vs the key isn't
mapped...
Finding three elements in an array whose sum is closest to a given number
...en an array of integers, A 1 , A 2 , ..., A n , including negatives and positives, and another integer S. Now we need to find three different integers in the array, whose sum is closest to the given integer S. If there exists more than one solution, any of them is ok.
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HTML5 LocalStorage: Checking if a key exists [duplicate]
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Quoting from the specification:
The getItem(key) method must return the current value associated with the given key. If the given key does not exist in the list associated with the object then this method must return null.
You should actually check against null....
Clear form fields with jQuery
I want to clear all input and textarea fields in a form. It works like the following when using an input button with the reset class:
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How do I redirect output to a variable in shell? [duplicate]
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This captures the output of a command, but it does not use a redirect. If you actually need to use a redirect because of a more complex need, See my answer. Google brought you here, right? Why go somewhere else to find the answer you searched for?
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How can I convert a string to a number in Perl?
I have a string which holds a decimal value in it and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string t...
How to vertically center divs? [duplicate]
... modern browsers is to use flexbox:
#Login {
display: flex;
align-items: center;
}
Some browsers will need vendor prefixes. For older browsers without flexbox support (e.g. IE 9 and lower), you'll need to implement a fallback solution using one of the older methods.
Recommended Reading
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