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Can an int be null in Java?
...// getA returns a null Integer
will give you a NullPointerException, despite object not being null!
To follow up on your question, if you want to indicate the absence of a value, I would investigate java.util.Optional<Integer>
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How can I clear event subscriptions in C#?
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From within the class, you can set the (hidden) variable to null. A null reference is the canonical way of representing an empty invocation list, effectively.
From outside the class, you can't do this - events basically expose "su...
Github Windows 'Failed to sync this branch'
I am using Github Windows 1.0.38.1 and when I click the 'Sync' button after committing, I get the error
17 Answers
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Invoking JavaScript code in an iframe from the parent page
...follow
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edited Mar 10 '16 at 20:38
Chris
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When to use static classes in C# [duplicate]
... my thoughts of static classes in an earlier Stack Overflow answer:
Class with single method -- best approach?
I used to love utility classes filled up with static methods. They made a great consolidation of helper methods that would otherwise lie around causing redundancy and maintenance hell. The...
Statistics: combinations in Python
...al.comb (scipy.misc.comb in older versions of scipy). When exact is False, it uses the gammaln function to obtain good precision without taking much time. In the exact case it returns an arbitrary-precision integer, which might take a long time to compute.
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Casting a variable using a Type variable
...object input) {
return (T) Convert.ChangeType(input, typeof(T));
}
Edit:
Some people in the comments say that this answer doesn't answer the question. But the line (T) Convert.ChangeType(input, typeof(T)) provides the solution. The Convert.ChangeType method tries to convert any Object to the ...
What is the right way to check for a null string in Objective-C?
...f "null" under Cocoa/Objective C. But one further thing to note is that [title isKindOfClass:[NSNull class]] is pointlessly complex since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title ...
Selenium WebDriver: Wait for complex page with JavaScript to load
I have a web application to test with Selenium. There is a lot of JavaScript running on page load.
This JavaScript code is not so well written but I can't change anything.
So waiting for an element to appear in the DOM with findElement() method is not an option.
I want to create a generic func...
Android 4.3 Bluetooth Low Energy unstable
... use Bluetooth Low Energy (testing on the Nexus 4). After getting started with the official BLE APIs in Android 4.3, I have noticed that after I connect a device for the first time I am rarely able to successfully connect to / communicate with that device or any other device again.
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