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Is null an Object?
...case - any method invocation on a null results in a NullPointerException.
And this is what the Java Language Specification has to say on this topic:
There is also a special null type, the
type of the expression null, which has
no name. Because the null type has no
name, it is impossible t...
How to interpret API documentation function parameters?
Is there a standard to interpret the syntax of function interfaces in API documentations and if yes, how is it defined?
4 A...
Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...
Since С99 the matching between format specifiers and floating-point argument types in C is consistent between printf and scanf. It is
%f for float
%lf for double
%Lf for long double
It just so happens that when arguments of type float are passed as variadic parameters,...
Check a collection size with JSTL
...r Facelets:
<... xmlns:fn="http://java.sun.com/jsp/jstl/functions">
And use like this in your page:
<p>The length of the companies collection is: ${fn:length(companies)}</p>
So to test with length of a collection:
<c:if test="${fn:length(companies) gt 0}">
</c:if>
A...
How to Select Columns in Editors (Atom,Notepad++, Kate, VIM, Sublime, Textpad,etc) and IDEs (NetBean
How to select columns in Editors and IDEs to columnar delete, insert or replace some characters ?
21 Answers
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How to get and set the current web page scroll position?
How can I get and set the current web page scroll position?
4 Answers
4
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Detect if Android device has Internet connection
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The best way to check if there is an active Internet connection is to try and connect
to a known server via http.
public static boolean hasActiveInternetConnection(Context context) {
if (isNetworkAvailable(context)) {
try {
HttpURLConnection urlc = (HttpURLConnection) (new...
How do I declare a global variable in VBA?
...
When I try to declare an array as public it says: array and user-defined data types can't be declared as public.
– kapilddit
Nov 13 '19 at 12:25
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Tools for JPEG optimization? [closed]
Do you know of any tools (preferrably command-line) to automatically and losslessly optimize JPEGs that I could integrate into our build environment? For PNGs I'm currently using PNGOUT , and it generally saves around 40% bandwidth/image size.
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How to distinguish between left and right mouse click with jQuery
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As of jQuery version 1.1.3, event.which normalizes event.keyCode and event.charCode so you don't have to worry about browser compatibility issues. Documentation on event.which
event.which will give 1, 2 or 3 for left, middle and right mouse buttons respectively so:
$('#element').mousedow...